JP5034337B2 - Method for determining operating conditions of membrane filtration device, and method of operating membrane filtration device using the same - Google Patents

Description

The present invention relates to a method for determining the operating conditions of a membrane filtration device for filtering a liquid through a separation membrane, a method for operating a membrane filtration device using the same, and a membrane filtration device, and more particularly, activated sludge, microbial culture solution, etc. the about the film method of determining the operating conditions of the membrane filtration apparatus, characterized in that the solid-liquid separation by filtration, and the operation how the membrane filtration device based thereon.

  As a method for filtering a liquid through a separation membrane, there is a method in which a liquid to be filtered is brought into contact with a separation membrane, and a filtrate is obtained by setting the filtered liquid side to a positive pressure or the permeate side to a negative pressure. In this membrane filtration step, non-membrane permeable substances contained in the liquid to be filtered accumulate on the membrane surface, and the accumulated substances cause an increase in membrane resistance. In order to suppress such an increase in membrane resistance, the membrane surface is aerated with an aeration device installed at the lower part of the separation membrane, or the liquid to be filtered is allowed to flow horizontally with the membrane surface using a pump or the like. Alternatively, a method of performing membrane filtration while washing the membrane surface by moving or vibrating the separation membrane is known. In such a membrane filtration method, it is possible to suppress an increase in membrane resistance by performing sufficient membrane cleaning. However, such membrane surface cleaning requires a large amount of energy supply and is more than necessary. In addition, extra energy is consumed when performing film cleaning. That is, it is important for the membrane filtration apparatus to properly operate the membrane surface that is necessary and sufficient, and contributes to energy saving and cost reduction.

  As a method for determining the degree of film surface cleaning, there is, for example, Patent Document 1. Patent Document 1 is a membrane filtration method using aeration as the membrane surface cleaning means, measuring the change over time of the membrane filtration pressure with respect to the operation time of the membrane filtration device, and increasing the membrane filtration pressure based on the measurement result. And a membrane filtration method for calculating the rate of change of the ascending rate and controlling the amount of aeration so that the membrane filtration pressure is constant or the calculated ascending rate or the rate of change of the ascending rate is a predetermined value. It is. According to Patent Document 1, as a means for determining the predetermined value, a method based on an experimental value as it is or a method based on an inferred value obtained by learning from an experimental value using a neural network or the like is proposed. ing.

  Moreover, in patent document 2, in the membrane filtration waste water treatment apparatus which performs the membrane filtration process, circulating the activated sludge which is a to-be-filtered liquid to a membrane module, it passes the said membrane module by the magnitude | size of the sludge density | concentration in a to-be-filtered liquid. The membrane filtration method which changes the membrane surface flow rate of the wastewater to be treated is proposed.

Japanese Patent No. 3572992 JP 2000-61466 A

  However, the membrane filtration method based on Patent Document 1 has the following problems. For example, if the membrane filtration pressure starts to gradually increase at the initial stage of operation when the membrane filtration pressure is kept constant, when the operator determines that this is the initial stage of operation, in order to keep the membrane filtration pressure constant. The aeration amount is increased, and when the operator determines that it is in the middle of operation, the aeration amount is adjusted so that the rate of increase in the membrane filtration pressure becomes a predetermined value. Thus, depending on the operator's judgment, there is an ambiguity that the aeration amount is different, and in the above example, if the operator judges that the operation is in the initial stage, the aeration amount may be increased more than necessary. If the operator judges, clogging of the film may be promoted.

  Further, the membrane filtration method of Patent Document 1 allows the membrane filtration pressure to gradually increase at the end of operation, and then the membrane clogging has progressed and the membrane has to be washed. In addition, the membrane filtration method of Patent Document 1 determines the initial, middle, and final operation from the behavior of the membrane filtration pressure, and adjusts the aeration amount. However, when the membrane filtration flux is changed during operation. The amount of aeration could not be determined based on the behavior before the change.

  Moreover, in the membrane filtration method based on patent document 2, even when a membrane filtration pressure and a membrane filtration flux change, although an appropriate membrane surface flow velocity changes, it cannot respond to a membrane filtration pressure or a membrane filtration flux. There was a drawback. In addition, although the membrane surface flow velocity is changed depending on the sludge concentration, it is not disclosed how to specifically change it, and it is difficult to determine control conditions suitable for the membrane filtration device. There were drawbacks.

The present invention has been made in response to these problems, and its purpose is to determine the degree of membrane surface detergency (hereinafter referred to as membrane detergency) suitable for sludge membrane filtration properties and membrane filtration conditions. And determining the operating conditions of the membrane filtration device that contributes to optimization of energy consumption, cost reduction, and reduction of the burden on the membrane filtration device by performing membrane filtration while cleaning the membrane surface based on the determined value, and there is provided a driving how the membrane filtration device based thereon.

  In order to solve the above-mentioned problem, it is essential that the method for determining the operating conditions of the membrane filtration device of the present invention has any of the following configurations.

(1) Using a membrane filtration apparatus having at least a separation membrane and a washing means for washing the surface of the separation membrane, the liquid to be filtered is filtered through the separation membrane, and the surface of the separation membrane is simultaneously or sequentially with filtration. This is a method for determining the operating conditions of a membrane filtration device that performs washing, and represents data representing the time-series changes in the type and amount of components of the filtrate and the time-series changes in the membrane filtration flow rate. From the data, predict fluctuations in the amount of constituents adhering to the separation membrane, fluctuations in membrane filtration pressure, or fluctuations in membrane resistance, determine the power value of the cleaning means based on the prediction results, and Prediction calculates the amount of component adhering to the separation membrane based on data representing the time-series change in the amount of component of the filtrate to be filtered and data representing the time-series change in the membrane filtration flow rate. Including calculation step 100 In addition, the calculation step 100 separates the change amount of the component amount adhering to the separation membrane from the separation membrane and the rate at which the substances contained in the components of the liquid to be filtered adhere to the separation membrane. The calculation step 101 is calculated based on a calculation formula expressed as a difference from the velocity, and the rate at which the substances contained in the constituent components of the liquid to be filtered peel from the separation membrane adheres to the separation membrane. A method for determining operating conditions of a membrane filtration device, comprising: determining based on a quadratic expression of values of constituent component amounts.

(2) Using a membrane filtration apparatus having at least a separation membrane and a washing means for washing the surface of the separation membrane, the liquid to be filtered is filtered through the separation membrane, and the surface of the separation membrane is simultaneously or sequentially with filtration. This is a method for determining the operating conditions of a membrane filtration device that performs washing, and represents data representing the time-series changes in the type and amount of components of the filtrate and the time-series changes in membrane filtration pressure. From the data, the fluctuation of the amount of constituents adhering to the separation membrane, the fluctuation of the membrane filtration flow rate, the fluctuation of the membrane filtration flux, or the fluctuation of the membrane resistance is predicted, and the power of the washing means is estimated based on the prediction result. A value is determined, and the prediction is attached to the separation membrane based on data representing a time-series change in the component amount of the filtrate to be filtered and data representing a time-series change in the membrane filtration pressure. Calculation to calculate the amount of component The calculation step 100 includes the change amount of the constituent component adhering to the separation membrane, the change amount of the constituent component adhering to the separation membrane, the rate at which the substance included in the constituent component of the liquid to be filtered adheres to the separation membrane, and the separation The calculation step 101 is calculated based on a calculation formula expressed as a difference from the rate of separation from the membrane, and the rate at which the substances contained in the constituents of the liquid to be filtered are separated from the separation membrane is the separation step. A method for determining operating conditions of a membrane filtration device, comprising determining the value based on a quadratic expression of values of constituent components adhering to the membrane.

  According to the present invention, an appropriate power value of the cleaning means is determined according to membrane filtration properties and membrane filtration conditions of various filtrates, and the membrane filtration apparatus is appropriately operated based on the determination result. It becomes possible.

  Here, in the conventional membrane filtration method, there was a problem that the aeration amount is different depending on the judgment of the operator, but according to the present invention, the membrane cleaning power can be objectively determined, The ambiguity that the membrane cleaning power differs depending on the operator's judgment can be resolved. In addition, the conventional membrane filtration method has allowed the membrane filtration pressure to gradually increase at the end of the operation, and then the membrane clogging has progressed and the membrane had to be washed. According to the present invention, it is possible to provide a membrane filtration method that does not promote clogging of the membrane even at the end of operation. In addition, in the conventional membrane filtration method, the initial, middle and final stages of operation are judged based only on the behavior of the membrane filtration pressure, and the amount of aeration is adjusted.If the membrane filtration flux is changed during operation, Although there was a problem that the amount of aeration could not be determined based on the behavior, according to the present invention, it is possible to respond quickly even when the membrane filtration flux is changed.

  Furthermore, the conventional membrane filtration method has a drawback in that it cannot cope with the membrane filtration pressure or the membrane filtration flux even though the membrane flow velocity changes when the membrane filtration pressure or the membrane filtration flux changes. However, according to the present invention, it is possible to determine an appropriate value of the membrane cleaning power in response to such changes in membrane filtration pressure and membrane filtration flux, and to perform a membrane filtration method based on the determined value. In particular, in the membrane filtration method of Patent Document 2, the membrane surface flow velocity is changed depending on the sludge concentration. However, it is not disclosed how to change the membrane surface, and is suitable for a membrane filtration device. Although it was difficult to determine the control conditions, according to the present invention, it is possible to objectively determine the membrane surface flow rate according to the sludge concentration.

  As described above, the power value of the proper cleaning means is determined according to the present invention, and the membrane filtration is performed while cleaning the membrane surface based on the determined power value of the cleaning means. This can contribute to a reduction in the burden on the membrane filtration device.

  Hereinafter, the present invention will be described in detail and specifically.

  The present invention uses a membrane filtration apparatus having at least a separation membrane and a washing means for washing the surface of the separation membrane, and filters the liquid to be filtered through the separation membrane, and simultaneously or sequentially with the filtration of the separation membrane. The present invention relates to a method for determining the operating conditions of a membrane filtration device for cleaning the surface. In the present invention, the cleaning means for cleaning the surface of the separation membrane includes aeration of the surface of the separation membrane, flowing the liquid to be filtered, moving the separation membrane, vibrating the separation membrane, etc. The form is not particularly limited as long as it has an effect of removing substances adhering to the membrane surface. However, when aeration is performed on the surface of the separation membrane, not only the liquid to be filtered flows along with the aeration, but also bubbles are formed in the membrane. Since it contacts the surface, the effect of peeling off the substance adhering to the separation membrane surface from the separation membrane surface is great. When the separation membrane is washed by aeration from the lower part of the separation membrane, the aeration may be aimed not only at washing the separation membrane but also supplying oxygen to the filtrate. In such a case, it is important to determine the necessary and sufficient amount of aeration air. As a determination method, the amount of aeration air necessary for cleaning the separation membrane determined as described later and the oxygen supply are required. A method of determining a large aeration air amount as an appropriate value for the aeration air amount, or when the aeration air amount necessary for oxygen supply is larger than the aeration air amount necessary for cleaning the separation membrane determined as described later. For example, there is a method in which the aeration air volume of the difference between the two is supplemented by an aeration apparatus separately installed in advance.

  In the present invention, the liquid to be filtered contains a suspended substance and is not particularly limited. For example, in the case of a liquid containing microorganisms, the liquid to be filtered generally contains a substance as a substance. Since microorganisms and microbial metabolites are present at a relatively high concentration, it is difficult to predict fluctuations such as resistance when the filtrate is subjected to membrane filtration. It is possible to predict fluctuations such as resistance at the time of filtration, and it is possible to accurately determine the power value of the washing means in the membrane filtration device for membrane filtration of the filtrate to be filtered. A liquid containing microorganisms such as activated sludge is preferable. In addition, when the concentration of suspended substances contained in the liquid to be filtered is large, separation of the film adhering substances by washing the membrane surface is particularly important. Therefore, in the present invention, the concentration of suspended substances is 100 mg / L or more. A liquid to be filtered is preferred.

  Further, in the present invention, the separation membrane has a function of capturing a substance having a certain particle diameter or more contained in the filtrate by applying pressure to the filtrate or sucking from the permeate side. Depending on the size of the trapped particles, there are dynamic filtration membranes, microfiltration membranes, ultrafiltration membranes, nanofiltration membranes, reverse osmosis membranes and the like. The separation membrane used in the present invention is preferably a dynamic filtration membrane, a microfiltration membrane, or an ultrafiltration membrane.

  In addition, examples of the shape of the separation membrane include a flat membrane and a hollow fiber membrane, but the shape is not particularly limited. Further, in the membrane filtration method and apparatus of the present invention, an immersion type membrane filtration method and apparatus characterized by immersing the separation membrane in the filtrate to be filtered, and the filtrate to be filtered is sent to a container containing the separation membrane. A cross-flow membrane filtration method and apparatus characterized by membrane filtration while rotating, and a rotary membrane filtration method characterized by rotating the separation membrane by immersing all or part of the separation membrane in the liquid to be filtered and There are devices. That is, as a method and apparatus preferably applicable to the present invention, there are a membrane-separated activated sludge method used for treatment of sewage, factory effluent, manure and the like, and a microbiological substance production process including a membrane separation step.

  The present invention uses a membrane filtration apparatus having at least a separation membrane and a washing means for washing the surface of the separation membrane, and filters the liquid to be filtered through the separation membrane, and simultaneously or sequentially with the filtration of the separation membrane. This is a method for determining the operating conditions of a membrane filtration device that cleans the surface, including the data representing the time-series changes in the type and amount of components of the liquid to be filtered, and the time-series changes in the membrane filtration flow rate. Predicting fluctuations in the amount of constituent components adhering to the separation membrane, fluctuations in membrane filtration pressure, or fluctuations in membrane resistance from the data to be represented, and determining the power value of the cleaning means based on the prediction results The method of determining the operating conditions of the membrane filtration device including the membrane filtration device (see FIG. 1) or the membrane filtration device having at least a separation membrane and a washing means for washing the surface of the separation membrane, Filtered and filtered A method for determining the operating conditions of a membrane filtration device for simultaneously or sequentially washing the surface of the separation membrane, the data representing the type of constituent components and the amount of constituent components of the liquid to be filtered, and From data representing time-series changes in membrane filtration pressure, predict fluctuations in the amount of components adhering to the separation membrane, fluctuations in membrane filtration flow, fluctuations in membrane filtration flux, or fluctuations in membrane resistance, It is the determination method (refer FIG. 2) of the operating condition of a membrane filtration apparatus including determining the power value of the said washing | cleaning means based on a prediction result.

  Here, the component of the liquid to be filtered is a component that constitutes the liquid to be filtered.For example, the liquid to be filtered is fractionated by centrifugation, filtration with filter paper, filtration with a separation membrane, and the like. The resulting liquid can be a constituent. Further, in the present invention, it is preferable to use a supernatant component or a solid component as a kind of constituent components of the liquid to be filtered, more preferably to use a supernatant component and a solid component, Most preferably, a dissolved component is utilized. Here, the supernatant component is, for example, a centrifugal supernatant obtained by centrifuging the liquid to be filtered, a separation membrane having a larger pore size than the separation membrane in the membrane filtration device (for example, a microfiltration membrane as a separation membrane in the membrane filtration device) In the case of using an ultrafiltration membrane or the like, it can be used as a filtrate when the filtrate is filtered using a filter paper or the like, and the solid component is obtained by, for example, centrifuging the filtrate. Using a separation membrane having a larger pore size than the separation membrane in the membrane filtration device (for example, a filter paper or the like when a microfiltration membrane or an ultrafiltration membrane is used as the separation membrane in the membrane filtration device) It can be set as the non-membrane filtrate thing when filtering a to-be-filtered liquid. The dissolved component is preferably a permeate from a separation membrane in a membrane filtration device or a separation membrane made of the same material as the separation membrane. Further, the component amount of the liquid to be filtered is a substance amount such as a dissolved substance or a suspended substance contained in the component, for example, total organic carbon (TOC), chemical oxygen demand ( COD), biochemical oxygen demand (BOD), extracellular polymer substance amount (EPS), suspended solids concentration (MLSS), dry weight, suspended solids loss on ignition (MLVSS), etc. . In the present invention, in view of ease of measurement, accuracy, and automation, it is recommended to specify the amount of substance measured based on the TOC.

  Further, in the present invention, it is preferable to use the difference amount between the substance amount of the supernatant component and the substance amount of the dissolved component as the constituent component amount, or to use the solid component substance amount as the constituent component amount. More preferably, the difference between the amount of the substance and the amount of the dissolved component and the amount of the solid component are used as the constituent amount. The amount of difference between the amount of the supernatant component in the liquid to be filtered and the amount of the dissolved component, and the amount of the solid component cannot be actually permeated through the membrane, and are resisted by adhering to the membrane surface. This is because the amount of the substance contributes to. In particular, when membranes are filtered, the substances that do not permeate the separation membrane in the membrane filtration device among the supernatant components of the filtrate (the amount of the substance is the amount of the supernatant component and the dissolved component) In most cases, the membrane resistance is mainly formed, and the amount of the component of the supernatant and the amount of the dissolved component are By using the difference amount, the component component amount of the filtrate to be filtered attached to the separation membrane, the fluctuation of the membrane filtration pressure, the fluctuation of the membrane filtration flow rate, the fluctuation of the membrane filtration flux, or more accurately It becomes possible to predict a change in the value of the membrane resistance. Moreover, the whole to-be-filtered liquid can be defined comprehensively and easily by using only the amount of solid components as a component amount of to-be-filtered liquid. In addition, substances contained in the solid component of the liquid to be filtered contribute to resistance if attached to the membrane, and are separated from the membrane in comparison with substances that do not permeate the separation membrane in the membrane filtration device among the supernatant components. Therefore, there is an effect that a substance that does not permeate the separation membrane in the membrane filtration device is entrained in the supernatant component adhering to the membrane and peeled off together. Therefore, by using the difference between the amount of the supernatant component and the amount of the dissolved component and the amount of the solid component as the component amount, the amount of the component of the liquid to be filtered attached to the separation membrane The above phenomenon can be reproduced when predicting fluctuations, fluctuations in membrane filtration pressure, fluctuations in membrane filtration flow rate, fluctuations in membrane filtration flux, or changes in the value of membrane resistance.

  In addition, the data representing the time-series change in the component amount of the liquid to be filtered is a time series combination of the values of the component components of the liquid to be filtered with respect to an arbitrary time. Although the value of the amount of the constituent component may fluctuate, it may be constant without fluctuating.

  The membrane filtration flow rate is the flow rate of the permeate obtained from the membrane. Further, the value obtained by dividing the value of the membrane filtration flow rate by the membrane area is the membrane filtration flux (that is, the membrane filtration flux is the membrane filtration flow rate per unit area of the separation membrane). Data representing a time-series change in the membrane filtration flow rate is a time-series combination of values of the membrane filtration flow rate for an arbitrary time, and the value of the membrane filtration flow rate may vary over time, It may be constant without changing. Alternatively, the value of the membrane filtration flow rate may be converted into a membrane filtration flux, and the data representing the time series change of the membrane filtration flow rate may be replaced with the data representing the time series change of the membrane filtration flux.

  The membrane filtration pressure is calculated as the difference between the pressure on the filtrate side of the separation membrane and the pressure on the permeate side. When the membrane filtrate is obtained by applying pressure or suction with a pump, Can be calculated from the water head difference or the like when the membrane filtrate is obtained using the siphon principle such as pressurization or suction pressure. The data representing the time-series change in the membrane filtration pressure is a time-series combination of the values of the membrane filtration pressure for an arbitrary time, and the value of the membrane filtration pressure may vary over time, It may be constant without changing.

  Moreover, the component amount adhering to the separation membrane is the amount of substance contained in the component of the liquid to be filtered adhering to the membrane surface. Here, when using two or more kinds of substance amounts (for example, the difference between the substance amount of the supernatant component and the substance amount of the dissolved component, the substance amount of the solid component, etc.) as the constituent component amount of the liquid to be filtered For each type of component, it means the amount of component adhering to the separation membrane.

The membrane resistance is a resistance generated when the liquid to be filtered is filtered through a membrane, and is generally defined by the equation (1).

Here, ΔP is the membrane filtration pressure [Pa], μ is the viscosity of the membrane filtrate [Pa · s], R is the membrane resistance [1 / m], and J is the membrane filtration flux [m / s]. Here, μ may directly measure the viscosity of the membrane filtrate, but may be converted from the temperature according to the equation (2).

ここで、Ｆ=0.01257187、Ｂ=−0.005806436、Ｃ＝0.001130911、Ｄ＝−0.000005723952であり、Ｔは絶対温度[K]である。すなわち、摂氏温度をσ[℃]とすると、Ｔ＝σ+273.15として表される。

Here, F = 0.01257187, B = −0.005806436, C = 0.001130911, D = −0.000005723952, and T is the absolute temperature [K]. That is, when the Celsius temperature is σ [° C.], it is expressed as T = σ + 273.15.

  In the present invention, the component adhering to the separation membrane from the data representing the time series change in the type and amount of the component of the liquid to be filtered and the data representing the time series change in the membrane filtration flow rate. Predicts fluctuations in volume, fluctuations in membrane filtration pressure, or fluctuations in membrane resistance (hereinafter referred to as prediction step 1), or represents time-series changes in the types and amounts of constituents of the liquid to be filtered From data and data representing time-series changes in membrane filtration pressure, fluctuations in the amount of components adhering to the separation membrane, fluctuations in membrane filtration flow rate, fluctuations in membrane filtration flux, or membrane resistance values The fluctuation is predicted (hereinafter referred to as prediction step 2).

  Here, the prediction is data representing a time-series change as an input (that is, in the case of the prediction step 1, data representing a time-series change in the type and amount of the component of the liquid to be filtered, and It is data representing a time-series change in the membrane filtration flow rate, and in the case of the prediction step 2, data representing a time-series change in the type and amount of components of the liquid to be filtered, and a time series of membrane filtration pressure From the target fluctuation (that is, in the case of the prediction step 1, the fluctuation of the component amount adhering to the separation membrane, the fluctuation of the membrane filtration pressure, or the value of the membrane resistance). In the case of the prediction step 2, the amount of the constituent component adhering to the separation membrane, the variation of the membrane filtration flow rate, the variation of the membrane filtration flux, or the variation of the membrane resistance value are included. Output as output It is. The means of the predicting step 1 or predicting step 2 includes a method of predicting based on the result of learning actual data using a neural network or the like, a membrane resistance value or a membrane filtration pressure as a function of input data. In the present invention, the data representing the time-series change in the component amount of the filtrate, the data representing the time-series change in the membrane filtration flow rate, or the membrane filtration It is preferable that the prediction method includes a calculation step 100 for calculating the value of the component amount adhering to the separation membrane based on data representing a time-series change in pressure. Accordingly, in the case of the prediction step 1, the fluctuation of the component amount adhering to the separation membrane, the fluctuation of the membrane filtration pressure, or the fluctuation of the membrane resistance value is changed. In the case of the prediction step 2, the separation membrane is changed. It is possible to more accurately predict fluctuations in the amount of constituents adhering to the membrane, fluctuations in the membrane filtration flow rate, fluctuations in the membrane filtration flux, or fluctuations in the value of the membrane resistance.

In addition, the calculation step 100 expresses the amount of change in the amount of the component adhering to the separation membrane as a difference between the rate at which the substance contained in the component of the liquid to be filtered adheres to the separation membrane and the rate at which the separation occurs. More preferably, the calculation step 101 is calculated based on the following calculation formula. Thus, it is possible to calculate the amount of change in the constituent component quantity attaching on the separation membrane, whereby, if the value of the constituent component quantity attaching on the separation membrane of any time t _i, a constant The value of the component amount adhering to the separation membrane at time t _{i + 1} can be calculated. In addition, even when the membrane filtration flow rate value, membrane filtration flux value, and membrane filtration pressure value are not constant and fluctuate, it is possible to calculate fluctuations in the amount of membrane adhesion of constituents of the liquid to be filtered. It becomes possible. Further, the rate at which the substances contained in the constituents of the liquid to be filtered peel from the separation membrane is determined based on a higher-order expression of the second or higher order of the amount of the constituent components adhering to the separation membrane. More preferably. Thus, in the case of the prediction step 1, the fluctuation of the component amount adhering to the separation membrane, the fluctuation of the membrane filtration pressure, or the fluctuation of the membrane resistance value is changed. In the case of the prediction step 2, the separation membrane is changed. It is possible to more accurately predict fluctuations in the amount of constituents adhering to the membrane, fluctuations in the membrane filtration flow rate, fluctuations in the membrane filtration flux, or fluctuations in the value of the membrane resistance.

  Further, the calculation formula expressing the amount of change in the amount of the supernatant component adhering to the separation membrane includes the value of the amount of the solid component adhering to the separation membrane, or the separation Most preferably, the calculation expression expressing the amount of change in the amount of the solid component adhering to the membrane is a calculation formula including the value of the amount of the supernatant component adhering to the separation membrane. As a result, the phenomenon that the substance contained in the solid component adhering to the separation membrane entrains the non-membrane-permeable substance contained in the supernatant component adhering to the membrane and peels off together (the solid of the liquid to be filtered If the component adheres to the membrane, it contributes to resistance, and it is easier to separate from the membrane compared to the non-membrane-permeable substance contained in the supernatant component). It is possible to accurately determine the power value of the cleaning means in the membrane filtration device to be filtered.

  Here, there are the following procedures as calculation procedures in the prediction step 1 and the prediction step 2.

  The prediction step 1 and the prediction step 2 include a calculation step 10 for calculating the value of the membrane filtration flux or the value of the membrane filtration pressure at an arbitrary time, and the value of the component amount adhering to the separation membrane at an arbitrary time. A calculation step 20 for calculating the film resistance, and a calculation step 30 for calculating the value of the membrane resistance at an arbitrary time. The calculation step 10, the calculation step 20 and the calculation step 30 are repeated while updating the time. Thus, in the prediction step 1 or the prediction step 2, it is possible to obtain a temporal change (that is, variation) of a value that is a prediction target.

  Here, in the calculation step 10, it is preferable to follow the equation (1). At this time, the expression (1) may be converted into the following expression (1 ').

ここで、Ｑは膜ろ過流量［ｍ^３／ｓ］、Ａは膜面積［ｍ^２］である。

Here, Q is the membrane filtration flow rate [m ³ / s], and A is the membrane area [m ² ].

  By using the expression (1) or (1 ′), the value of the membrane filtration pressure at an arbitrary time in the case of the prediction step 1 or the value of the membrane filtration flow rate at an arbitrary time in the case of the prediction step 2 The value of the membrane filtration flux can be calculated.

  Further, in the calculation step 20, as described above, the amount of change in the amount of the constituent component adhering to the separation membrane is determined based on the rate at which the substance contained in the constituent component of the liquid to be filtered adheres to the separation membrane. It is preferable that the calculation step 101 is calculated based on a calculation expression expressed as a difference between and the calculation expression expressing the amount of change in the amount of substance of the supernatant component adhering to the separation membrane, A calculation formula that includes the value of the amount of the solid component adhering to the separation membrane or the amount of change in the value of the amount of the solid component adhering to the separation membrane is expressed by the separation membrane. More preferably, the calculation formula includes the value of the amount of the supernatant component adhering to the surface. Examples of such calculation formulas include the following formulas (3) and (4). In the present invention, it is recommended to follow the formulas (3) and (4). However, the scope of the present invention is not limited to the equations (3) and (4).

ただし、（τ−λｘ・ΔＰ）≧０、（τ−λｐ・ΔＰ）≧０である。

However, (τ−λx · ΔP) ≧ 0 and (τ−λp · ΔP) ≧ 0.

Here, X is the amount of the substance contained in the solid component [gC / m ³ ], P is the amount of the non-membrane permeable substance contained in the supernatant component [gC / m ³ ], and Xm is the separation per unit membrane area The amount of substance contained in the solid component adhering to the membrane [gC / m ² ], Pm is the amount of substance of the non-membrane permeable substance contained in the supernatant component adhering to the separation membrane per unit membrane area [gC / m ² ] , T is time [s], τ is membrane detergency [−], γx is the peel coefficient [1 / m / s] of the substance contained in the solid component, and γp is the non-membrane permeable substance contained in the supernatant component. Peel coefficient [1 / m / s], λx is the friction coefficient [1 / Pa] of the substance contained in the solid component, λp is the friction coefficient [1 / Pa] of the non-membrane permeable substance contained in the supernatant component, ηx the inverse of the density of the substance contained in the solid component [m 3 ^/ gC], ηp is the reciprocal of the density of non-membrane permeable substance contained in the supernatant component [ It is a ³ / gC]. Here, the first term on the right side of the equations (3) and (4) is the speed at which the substance contained in the constituent component adheres to the separation membrane, and the second term is the substance in which the constituent component is contained in the separation membrane. It shows the speed of peeling from. Further, by multiplying both sides of the formulas (3) and (4) by the membrane area A, the left side of the formula (3) is the amount of change in the amount of substance contained in the solid component attached to the separation membrane, and the formula (4) It is possible to convert the membrane filtration flux J on the right side into the membrane filtration flow rate Q to the amount of change in the amount of the non-membrane permeable substance contained in the supernatant component attached to the separation membrane on the left side. Further, as will be described later, when the membrane cleaning power τ is expressed as a function of the power value of the cleaning means, by substituting the function into τ, the expressions (3) and (4) Instead, it can be converted into a calculation formula relating to the power value of the cleaning means.

  Further, as described above, the amount of change in the amount of the constituent component adhering to the separation membrane is expressed as the difference between the rate at which the substance contained in the constituent component of the liquid to be filtered adheres to the separation membrane and the rate at which the separation is performed. Is expressed as a differential equation related to the amount of constituents of the liquid to be filtered attached to the separation membrane. At that time, as a method for solving this differential equation, the Euler method, the Runge-Kutta method, the Runge method, and the like. -Kutta-Gill (RKG) method.

  By performing the calculation step 20 as described above, the value of the component amount adhering to the separation membrane at an arbitrary time can be calculated.

  In the calculation step 30, for example, the value of the membrane resistance at an arbitrary time can be calculated by following the equation (5).

ここで、Ｒｍは初期膜抵抗の値［１／ｍ］、αｘは前記Ｘｍの単位量あたりの抵抗発生量［ｍ／ｇＣ］、αｐは前記Ｐｍの単位量あたりの抵抗発生量［ｍ／ｇＣ］である。

Here, Rm is the initial film resistance value [1 / m], αx is the resistance generation amount per unit amount of Xm [m / gC], and αp is the resistance generation amount per unit amount of Pm [m / gC]. ].

  As described above, it is possible to calculate the fluctuation of the value to be predicted by the three calculation steps of the calculation step 10, the calculation step 20, and the calculation step 30, but only the fluctuation of the film resistance value is calculated. In the case of prediction, the calculation step 10 may be omitted, and the calculation step 20 and the calculation step 30 may be used. For example, in the calculation step 20, in the case of the prediction step 1, when a calculation formula including the value of the membrane filtration pressure (for example, the formula (3) or the formula (4)) is used, the membrane filtration pressure is calculated in the calculation step 10. By using, in the calculation step 20, a calculation formula in which a calculation formula (for example, formula (1)) used for calculation of the value is substituted into a calculation formula including the value of the membrane filtration pressure in the calculation step 20, the membrane The calculation step for calculating the value of the filtration pressure can be omitted, and in the case of the prediction step 2, when using a calculation formula (for example, formula (3) or formula (4)) including the value of the membrane filtration flow rate or the membrane filtration flux The calculation formula (for example, the formula (1)) used for calculating the value of the membrane filtration flow rate and the membrane filtration flux in the calculation step 10 is changed to the value of the membrane filtration flow rate and the membrane filtration flux in the calculation step 20. Including formula By using the assignment was equation to the calculation step 20, it can be omitted calculating step of calculating the value of the membrane filtration pressure. Similarly, in the prediction step 1, only the fluctuation of the value of the membrane filtration pressure is predicted, and in the case of the prediction step 2, only the fluctuation of the value of the membrane filtration flow rate or the membrane filtration flux is predicted, the calculation step 30 may be omitted, and the calculation step 10 and the calculation step 20 may be configured by two calculation steps. For example, in the calculation step 10, when a calculation formula including the value of the membrane filtration resistance (for example, the equation (1)) is used, a calculation formula (for example, (5) used for the calculation of the value of the membrane resistance in the calculation step 30. The calculation step 30 can be omitted by using, in the calculation step 10, a calculation formula obtained by substituting the formula ()) into the calculation formula including the film resistance value in the calculation step 10. As described above, calculation step 10 or calculation step 30 can be omitted as appropriate, but it is recommended not to omit calculation step 20.

  Further, in the calculation step 10, the calculation step 20, and the calculation step 30, calculation is performed according to a predetermined calculation formula. Values, data, and data described in the description of each calculation step are included in the calculation formulas. Parameters other than the amount of substances may be included. In such a case, it is necessary to determine a parameter value in performing the calculation in each calculation step. In the present invention, the method for determining the parameter value is not particularly limited. However, using a separation membrane having the same material and shape as the separation membrane of the membrane filtration device, the filtrate or the components of the filtrate are actually filtered. It is preferable to measure or calculate changes in the value of the membrane filtration pressure, the value of the membrane filtration flux or the membrane filtration flow rate, and the value of the membrane resistance at that time, and estimate or determine the parameters based on the results. This includes many parameters determined by the properties of the liquid to be filtered and the separation membrane used, and by following the parameter estimation / determination method described above, This is because the prediction can be performed with high accuracy, and the power value of the cleaning means in the membrane filtration device that performs membrane filtration of the liquid to be filtered can be determined with high accuracy.

  In the present invention, the power value of the cleaning means is determined based on the result predicted as described above. As a method for determining the power value of the cleaning means, from the value of the virtual membrane cleaning power, the fluctuation of the amount of components adhering to the separation membrane, the fluctuation of the membrane filtration pressure, the fluctuation of the membrane filtration flow rate, the membrane filtration Fluctuation in flux or membrane resistance is predicted, and based on the prediction result, the value of the virtual membrane cleaning power is determined. The virtual result determined to be good in the determination result. An appropriate value of the membrane cleaning power is determined from the value of the membrane cleaning power, and the power value of the cleaning means is determined based on the determined appropriate value of the membrane cleaning power, or the power of the virtual cleaning means is determined. From the value, the fluctuation of the amount of components adhering to the separation membrane, the fluctuation of the membrane filtration pressure, the fluctuation of the membrane filtration flow rate, the fluctuation of the membrane filtration flux, or the fluctuation of the membrane resistance is predicted, and the prediction result Based on the power value of the virtual cleaning means. An appropriate value of the power of the cleaning means is determined from a power value of the virtual cleaning means determined to be good in the determination result, and based on the determined appropriate value of the power of the cleaning means, It is preferable to determine the power value.

  Here, the film cleaning force is a stress for peeling off the film adhering substance adhering to the film surface, and the value of the film cleaning force is the value of the shearing force generated on the film surface and the amount of the film surface covered. It is preferable to set the value of the flow rate of the filtrate, the value calculated based on the shearing force and the flow rate, or the value calculated based on the power value of the cleaning means, etc. By determining the value of the membrane cleaning power with respect to the power value of the cleaning means based on the result calibrated by the prediction method including the calculation step 100 or the calculation step 101, the value of the membrane cleaning power and the cleaning means It is also preferable to determine from the result of obtaining the relationship with the power value. This makes it possible to directly calculate the membrane cleaning power, such as directly measuring, multiplying the safety factor, or expressing it as a function.

  The power value of the cleaning means corresponds to, for example, the amount of aeration air or the output value of the aeration blower when the separation membrane is cleaned by aeration from the lower part of the separation membrane. When the flow is performed, the power for generating the flow (for example, the output value of the liquid pump when the liquid to be filtered is flowed by the liquid pump) corresponds to the cleaning of the separation membrane. When moving by moving, it corresponds to the moving speed and the power value for that (for example, in the case of a rotary filtration membrane, the rotational speed and the output value of the motor for generating the rotation), etc. When it is performed by vibrating, it means the degree of vibration (for example, frequency) and the power value (for example, output value of the motor) for that purpose.

  In addition, the value of the virtual membrane cleaning power and the power value of the virtual cleaning means are the fluctuation of the amount of constituents adhering to the separation membrane, the fluctuation of the membrane resistance, the fluctuation of the membrane filtration flow rate, the membrane filtration flux. It is a value set on the assumption that it is used for predicting fluctuations in the pressure or fluctuations in membrane filtration pressure. Here, virtual means that it does not necessarily depend on actual data, and may be different from an appropriate value of the film cleaning power finally determined and an appropriate value of the power of the cleaning means. It is based on the assumption.

  In addition, as a method for determining whether or not the value of the virtual membrane cleaning power or the power value of the virtual cleaning means is determined based on the prediction result, the value is attached to the separation membrane. The value of the component amount, the value of membrane resistance or the value of membrane filtration pressure is not more than a predetermined value, or the value of membrane filtration flux or the value of membrane filtration flow rate is not less than a predetermined value. Sometimes, it is determined that the virtual membrane cleaning power value or the virtual power value of the cleaning means is correct, and in the prediction result, the amount of component adhering to the separation membrane When the value, the value of the membrane resistance, or the value of the membrane filtration pressure converges, it is preferable to determine that the virtual membrane cleaning power value or the virtual power value of the cleaning means is good. This makes it possible to objectively determine the appropriate value of the membrane cleaning power or the appropriate power of the cleaning means.

  Here, the predetermined value needs to be set in advance, but the predetermined value is determined based on the maximum output value of the pump that generates the membrane filtration pressure, and the energy consumption of the pump that generates the membrane filtration pressure. A method of determining based on the maximum allowable value, a method of determining based on the maximum allowable value of the membrane resistance value and the membrane filtration pressure value to increase the membrane life and cleaning interval, and the pre-planned membrane filtration flow rate In order to satisfy, the method of determining based on the permissible minimum value of the value of the membrane filtration flux and the value of the membrane filtration flow rate is exemplified. For example, if the predetermined value is the maximum output value of the pump that generates the membrane filtration pressure, when the membrane filtration conditions are judged to be non-existing, the initially scheduled membrane filtrate volume cannot be obtained. When the condition is determined to be good, the expected amount of membrane filtrate can be obtained.

  Further, in the present invention, an appropriate value of the film cleaning power is determined from the virtual film cleaning power value determined as good in the determination result, or the virtual value determined as good in the determination result. The appropriate power value of the cleaning means is determined from the power value of the cleaning means. For the purpose of energy saving and cost reduction of membrane filtration, it is preferable that the power value of the cleaning means is as small as possible, and the membrane cleaning power increases as the power value of the cleaning means increases. It is preferable that the value is as small as. Therefore, the virtual film cleaning power value that is the smallest among the virtual film cleaning power values determined to be good in the determination result is set as an appropriate value of the film cleaning power, and the determination result It is preferable that the power value of the virtual cleaning means that is the smallest among the power values of the virtual cleaning means determined to be right is set to an appropriate value of the power of the cleaning means.

  As a method for determining the appropriate value of the film cleaning force or the appropriate value of the power of the cleaning means described above, for example, there is a method shown in FIG. FIG. 5 is an example of a flowchart for carrying out the present invention. First, data representing a time-series change in the amount of constituents of the liquid to be filtered, data representing a time-series change in the membrane filtration flow rate, and n arbitrary values of virtual membrane cleaning power or virtual Prepare the power value of the appropriate cleaning means. Using data representing time-series changes in the amount of constituents of the filtrate to be filtered and data representing time-series changes in membrane filtration flow rate, virtual membrane cleaning power values or virtual cleaning means power values For this, the first value (the membrane cleaning power 1 or the power value 1) is used. Here, when the prediction step 1 is used, based on these data and values, fluctuations in the amount of constituent components adhering to the separation membrane based on the prediction step 1, fluctuations in membrane filtration pressure, or membrane resistance And predicting the value of the virtual film cleaning power or the power value of the virtual cleaning means based on the prediction result. This determination result is referred to as determination result 1. Similarly, prediction is performed using the second to n-th virtual membrane cleaning power values or the power values of the virtual cleaning means, and the virtual membrane cleaning power value based on the prediction result. Alternatively, it is determined whether the power value of the virtual cleaning means is appropriate, and determination results 2 to n are obtained. Based on the determination results 1 to n obtained as described above, an appropriate value for the film cleaning power or an appropriate value for the power of the cleaning means is determined. Here, when the prediction step 2 is used, based on these data and values, fluctuations in the amount of constituent components adhering to the separation membrane based on the prediction step 1, fluctuations in the membrane filtration flow rate, membrane filtration flow The fluctuation of the bundle or the fluctuation of the membrane resistance is predicted, and the value of the virtual film cleaning power or the power value of the virtual cleaning means is determined based on the prediction result. This determination result is referred to as determination result 1. Similarly, prediction is performed using the second to n-th virtual membrane cleaning power values or the power values of the virtual cleaning means, and the virtual membrane cleaning power value based on the prediction result. Alternatively, it is determined whether the power value of the virtual cleaning means is appropriate, and determination results 2 to n are obtained. Based on the determination results 1 to n obtained as described above, an appropriate value for the film cleaning power or an appropriate value for the power of the cleaning means is determined.

  In the present invention, when it is determined in the determination result that the value of the virtual film cleaning power is not, the virtual film cleaning power value is increased by a predetermined amount, and then the virtual film cleaning power is increased again. From the value of the detergency, predict fluctuations in the amount of components adhering to the separation membrane, fluctuations in the membrane filtration pressure, fluctuations in the membrane filtration flow rate, fluctuations in the membrane filtration flux, or fluctuations in the membrane resistance, Based on the prediction result, determining whether the value of the virtual film cleaning power after the predetermined amount is increased, and when determining that the value of the virtual film cleaning power is good in the determination result The virtual film cleaning power is set to an appropriate value for the film cleaning power, or the virtual power value of the virtual cleaning means is determined to be non-determined in the determination result. After increasing the power value of the cleaning means by a predetermined amount, the virtual cleaning is performed again. From the power value of the stage, the fluctuation of the amount of constituents adhering to the separation membrane, the fluctuation of the membrane filtration pressure, the fluctuation of the membrane filtration flow rate, the fluctuation of the membrane filtration flux, or the fluctuation of the membrane resistance are predicted, Based on the prediction result, it is determined whether the power value of the virtual cleaning means after the predetermined amount is increased, and in the determination result, the power value of the virtual cleaning means is determined to be good. In some cases, it is preferable that the imaginary power value of the cleaning means is an appropriate value of the power of the cleaning means.

  For example, in FIG. 3 (when the prediction step 1 is used) and FIG. 4 (when the prediction step 2 is used), a change step 40 for changing the virtual membrane cleaning power value or the virtual cleaning means power value is provided. The example of the flowchart in the case of having been shown is shown. Here, first, a sufficiently small value of the virtual film cleaning power or a virtual power value of the cleaning means is prepared, and prediction is performed by the prediction step 1 or the prediction step 2. A virtual membrane cleaning power value or a virtual cleaning means power value is determined from the prediction result. The power value of a typical cleaning means is increased by a predetermined amount, and the prediction step 1 or the prediction step 2 and subsequent steps are repeated again. At this time, the virtual membrane cleaning force value or the virtual cleaning means power value used when the judgment result is positive is set to the appropriate value of the membrane cleaning power or the appropriate power value of the cleaning means, respectively. If such a procedure is followed, the appropriate value of the membrane cleaning power or the appropriate power of the cleaning means can be determined more efficiently than the procedure shown in FIG. In addition, in the changing step 40, the virtual film cleaning power value between the virtual film cleaning power value for which the determination result is good and the virtual film cleaning power value for which the determination result is non is changed. Thus, in the method of gradually reducing the range estimated as the appropriate value of the film cleaning power, or in the change step 40, the power value of the virtual cleaning means for which the determination result is good, and There is a method of gradually reducing the range estimated as the appropriate value of the power of the cleaning means by changing to a virtual power value of the cleaning means between the power value, but if such a method is followed, When determining the appropriate value of the membrane cleaning power or the appropriate power of the cleaning means, it is preferable to follow the procedure shown in FIG. 3 or FIG.

  In the present invention, the power value of the cleaning means is determined based on the determined appropriate value of the power of the cleaning means. At this time, the appropriate value of the power of the cleaning means may be determined as it is as the power value of the cleaning means, and in the membrane filtration device targeted by the present invention, when the membrane cleaning power is smaller than a necessary and sufficient amount In order to reduce the risk of causing rapid film clogging, the safety value of the cleaning means may be multiplied by a certain value as a safety factor, or a certain value may be added to make it safer.

  In the present invention, the power value of the cleaning means is determined based on the determined appropriate value of the film cleaning power. At this time, it is preferable to determine an appropriate value of the power of the cleaning means based on the appropriate value of the membrane cleaning power, and to determine the power value of the cleaning means based on the determined appropriate value of the power of the cleaning means. . As the method, the value of the shear force generated on the membrane surface with respect to the power of an arbitrary cleaning means, or the value of the flow rate of the liquid to be filtered on the membrane surface is obtained, and the value of the shear force generated on the membrane surface, or the membrane surface By determining the value of the membrane cleaning power based on the value of the flow rate of the liquid to be filtered, the relationship between the value of the membrane cleaning power and the power value of the cleaning means is obtained, and the appropriateness of the membrane cleaning power is determined based on the above relationship. In the membrane filtration apparatus that can measure the value of the power of the cleaning means from the value, the value of the shear force generated on the separation membrane surface or the flow rate of the liquid to be filtered on the membrane surface, Expressing the relationship between the value of the shear force generated on the membrane surface or the value of the flow rate of the liquid to be filtered on the membrane surface as a function, the value of the shear force corresponding to the appropriate value of the membrane cleaning force (appropriate value of shear force) Or the value of the flow rate (appropriate flow rate ) And the measured value of the shearing force generated on the surface of the separation membrane or the measured value of the flow rate of the liquid to be filtrated on the surface of the membrane becomes the determined appropriate value of the shearing force or the appropriate value of the flow rate. A method of adjusting the power value, the value of the membrane cleaning power relative to the power value of any cleaning means is determined based on the result of calibration described later, and the relationship between the value of the membrane cleaning power and the power value of the cleaning means And determining an appropriate value of the power of the cleaning means from an appropriate value of the film cleaning power.

  In the present invention, the value of the membrane cleaning power with respect to the power value of the arbitrary cleaning means is determined based on the result of calibration in the prediction step 1 or the prediction step 2, so that the value of the membrane cleaning power and the cleaning means are determined. It is preferable to determine the appropriate value of the power of the cleaning means from the appropriate value of the membrane cleaning power based on the relationship. Here, the calibration means that the difference between the prediction result of the membrane resistance prediction step when the value of the membrane cleaning power is given as virtual data and the actual value observed and measured when the membrane is actually filtered are small. It is to obtain such a film cleaning power. As a method for this, in the present invention, it is recommended to follow a calibration procedure 200 or a calibration procedure 210 as follows.

The calibration procedure 200 is as follows.
(1) In a membrane filtration apparatus, an arbitrary constant membrane cleaning power is applied under an arbitrary membrane filtration flux pattern or membrane filtration flow rate pattern (that is, while the power value of the cleaning means is kept constant). The filtrate is subjected to membrane filtration through a separation membrane, and the change in the value of membrane filtration pressure or membrane resistance during the filtration process is measured.

(2) Data representing a time-series change of the membrane filtration flux or the membrane filtration flow rate and data representing a time-series change of the component amount of the liquid to be filtered in the membrane filtration of (1) are prepared.
(3) The membrane filtration pressure value or membrane resistance in the membrane filtration process when an arbitrary membrane cleaning power value is given as virtual data based on the data prepared in (2) by the prediction step 1 Calculate the change in the value of.

(4) Changes in the value of membrane filtration pressure or membrane resistance in the membrane filtration process measured in (1) above, and the value of membrane filtration pressure or membrane resistance in the membrane filtration process calculated in (3) above Find the integral (sum) of the difference from the change in value.
(5) The value of the film cleaning power given by (3) is changed.

  (6) Repeating the above (2) to (5), the value of the membrane cleaning power given as virtual data, and the membrane filtration pressure in the membrane filtration process measured in (1) obtained in the above (4) And the integral value (sum) of the difference between the change in the value of the membrane resistance or the value of the membrane resistance and the value of the membrane filtration pressure or the change in the membrane resistance in the membrane filtration process calculated in (3).

  (7) The value of the membrane detergency given as virtual data obtained in the above (6) and the value of the membrane filtration pressure in the membrane filtration process measured in the above (1) obtained in the above (4) or From the set of integral values (sum) of differences between the change in the value of the membrane resistance and the value of the membrane filtration pressure or the value of the change in the membrane resistance calculated in the membrane filtration process in (3) above (4) ) And the change in the membrane filtration pressure value or membrane resistance value in the membrane filtration process measured in (1) above, and the calculated membrane filtration pressure value or membrane resistance in the membrane filtration process in (3) above. The value of the film cleaning power that minimizes the integrated value (sum) of the difference from the change in the value of the value is the constant film cleaning power value given in (1) above.

  The calibration procedure 210 is as follows.

  (11) In the membrane filtration apparatus, the membrane to be filtered is separated by the separation membrane while giving an arbitrary constant membrane cleaning power (that is, keeping the power value of the cleaning means constant) under an arbitrary membrane filtration pressure pattern. Filter and measure changes in membrane filtration flux, membrane filtration flow, or membrane resistance during the filtration process.

(12) Data representing a time-series change in the membrane filtration pressure and data representing a time-series change in the component amount of the liquid to be filtered in the membrane filtration of (11) are prepared.
(13) Membrane filtration flux or membrane filtration flow rate in the membrane filtration process when an arbitrary value of membrane cleaning power is given as virtual data based on the data prepared in (12) by the prediction step 2 Or change in the value of the membrane resistance.

(14) Changes in the value of membrane filtration flux or membrane filtration flow rate or membrane resistance in the membrane filtration process measured in (11) above, and the membrane filtration flux in the membrane filtration process calculated in (13) above Alternatively, the integral value (sum) of the difference between the value of the membrane filtration flow rate or the change in the value of the membrane resistance is obtained.
(15) The value of the film cleaning force given by (13) is changed.

  (16) Repeating the above (12) to (15), the value of the membrane cleaning power given as virtual data, and the membrane filtration flow in the membrane filtration process measured in the above (11) obtained in the above (14) Integration of the difference between the change in the bundle or membrane filtration flow rate value or the membrane resistance value and the change in the membrane filtration flux value or membrane filtration flow rate value or membrane resistance value in the membrane filtration process calculated in (13). Find a set of values (sum).

  (17) The value of the membrane cleaning power given as virtual data obtained in the above (16) and the membrane filtration flux or membrane in the membrane filtration process measured in the above (11) obtained in the above (14) The integrated value (sum) of the difference between the change in the value of the filtration flow rate or the membrane resistance and the change in the value of the membrane filtration flux or the membrane filtration flow rate or the membrane resistance in the calculated membrane filtration process in (13) ) From the set of (14), the change in the value of membrane filtration flux or membrane filtration flow rate or membrane resistance in the membrane filtration process measured in (11) above, and in (13) above The value of the membrane cleaning power that minimizes the integral value (sum) of the difference between the calculated value of the membrane filtration flux or the membrane filtration flow rate or the change of the membrane resistance in the membrane filtration process is given in the above (11). Constant membrane cleaning power And value.

  Here, the membrane filtration flux pattern or the membrane filtration flow rate pattern in the above (1) or the membrane filtration pressure pattern in the above (11) is the value of the membrane filtration flux in the actual operation of the membrane filtration device, respectively. Those that vary within the range of the value of the membrane filtration flow rate or the value of the membrane filtration pressure are preferred, and when intermittent operation is performed in an actual membrane filtration device, those that include intermittent conditions are preferred. This makes it possible to determine the film cleaning power with high accuracy. The membrane resistance prediction method used in the above (3) or (13) performs another membrane filtration test using the same filtrate and separation membrane, and the membrane filtration pressure value, membrane filtration flux or It is preferable to use one that has been confirmed to sufficiently predict the change in the membrane filtration flow rate or the membrane resistance value. The change in (5) or (15) is preferably an increase or decrease of a predetermined value. Here, by setting the predetermined value as small as possible, the value of the membrane cleaning power can be determined more accurately.

  Further, the value of the hypothetical membrane cleaning power used in (3) is first given from a sufficiently small value, the change in (5) is assumed to be an increase of a predetermined value, and the integral value obtained in (4) is The calculation is stopped when the calculated value is larger than the previous calculated value, and the virtual film cleaning power value used in (3) in the previous calculation is determined as the value of the film cleaning power given in (1). Or the virtual membrane cleaning power value used in (13) is given from a sufficiently small value, the change in (15) is increased by a predetermined value, and the integration obtained in (14) When the value becomes larger than the previous calculation value, the calculation is stopped, and the virtual film cleaning power value used in (13) in the previous calculation is set as the value of the film cleaning power given in (11). I also like the way to decide There. However, when the virtual membrane cleaning power value used in (3) is plotted on the horizontal axis, and the membrane cleaning power value that minimizes the relationship between the integral values obtained in (4) is plotted on the vertical axis. In addition, since the minimum value is not necessarily one, the predicted result in (3) when using the determined value of the membrane cleaning power is compared with the actually measured value in (1), When the virtual membrane cleaning power value used in (13) is plotted on the horizontal axis, and the membrane cleaning power value that minimizes the relationship between the integral values obtained in (14) is plotted on the vertical axis, Since the minimum value is not always one, it is desirable to compare the predicted result in (13) and the actually measured value in (11) when the determined value of the film cleaning power is used.

  According to such a procedure, it is possible to accurately obtain the membrane cleaning force required in the present invention, and by determining the power value of the cleaning means based on this, the appropriate value of the power of the cleaning means is accurately determined. Can be determined. Specific examples thereof will be described in Example 1.

  Further, in the present invention, based on the operating conditions of the membrane filtration device determined as described above, the operation value of the membrane filtration device is controlled, and at least the separation membrane, A membrane filtration apparatus having a cleaning means for cleaning the surface of the separation membrane, and a control means for controlling the operation of the cleaning means, wherein the control means satisfies the operating conditions of the membrane filtration apparatus determined as described above. The present invention provides a membrane filtration device that controls the operation of the cleaning means. Here, it is preferable to control the power value of the cleaning means by using an inverter provided with an inverter whose power can be varied as the cleaning means.

  Hereinafter, the present invention will be described in detail, but the present invention is not limited to only these examples.

Example 1
An outline of the structure of the membrane filtration device 500 used in this example is shown in FIG. The membrane filtration device 500 is a submerged membrane separation activated sludge device, and is a wastewater treatment device for treating factory wastewater containing acetic acid as a main component. The raw water 506, industrial wastewater mainly composed of acetic acid, was intermittently charged into the filtrate storage tank 501 having an average flow rate of 2.3 m ³ / d and an effective capacity of 2.3 m ³ . Activated sludge is accommodated in the filtrate receiving tank 501 as the filtrate to be filtered 504, and the separation membrane 502 is immersed in the filtrate to be filtered 504, and an aeration tube 507 is installed below the separation membrane 502. The air diffusing tube 507 is configured to be supplied with air from an aeration blower 503 serving as a cleaning means. That is, in this apparatus, since the air bubbles supplied from the diffuser tube 507 come into contact with the membrane surface, and the activated sludge flows due to aeration, the adhering components on the membrane surface are separated from the membrane. It will be. Here, a flat membrane type microfiltration membrane (effective membrane area 7.8 m ² ) made of PVDF (polyvinylidene fluoride) is used as the separation membrane 502, and a suction pump installed on the membrane permeate side is membrane filtered. Used as liquid acquisition means 505.

Moreover, in the present Example, the component amount of the to-be-filtered liquid was defined and measured as follows. The liquid to be filtered consists of a solid component (substance amount: X [gC / m ³ ]), a non-membrane filtration component in the supernatant (substance amount: P [gC / m ³ ]), and a dissolved component (substance amount: S [gC / m ³ ]). X is determined by measuring MLSS [gC / m ³ ] of the liquid to be filtered in accordance with the sewer test method, assuming that its characteristic formula is C ₅ H ₇ O ₂ N, and multiplying the measured value by 60/113. Calculated with S measured the TOC [gC / m ³ ] of the membrane filtrate obtained in the membrane filtration device 500, and set it as the measured value. P represents the difference between the measured TOC [gC / m ³ ] and S [gC / m ³ ] of the supernatant component by centrifuging the liquid to be filtered (3500 rpm, 10 minutes) to obtain the supernatant component. Calculated. As a result, X was 1731 [gC / m ³ ], P was 24 [gC / m ³ ], and S was 3.6 [gC / m ³ ].

  Further, in this embodiment, in the prediction step 1, the fluctuation of the film resistance value is predicted. Here, using the equation (1) as the calculation step 10 (where μ uses the equation (2)), and using the equation (3) and the equation (4) as the calculation step 20, The equation (5) was used as the calculation step 30.

  In this example, a membrane filtration prediction program was created using numerical calculation software MATLAB (made by Mathworks, USA), and the above calculation was performed. Here, the Runge-Kutta method was used as the integration method. Further, in this example, each specification value used for performing the above calculation is summarized in Table 1.

  Here, among the specification values shown in Table 1, the resistance coefficients αx and αp, the peeling coefficients γx and γp, and the friction coefficients λx and λp were determined as follows.

  First, the activated sludge was used as a liquid to be filtered, and a membrane filtration test was performed using the membrane filtration test apparatus 400 shown in FIG. The membrane filtration test apparatus 400 pressurizes a pure water chamber 410 containing pure water or a stirring cell 401 (Amicon 8050 manufactured by Millipore Corporation) with nitrogen gas 405 (the pressure is measured by a pressure gauge). ), The activated sludge as the liquid to be filtered by the separation membrane 402 installed in the membrane fixing holder 406. In membrane filtration, the liquid to be filtered can be stirred by rotating a stirring bar 404 immersed in the liquid to be filtered by a magnetic stirrer 403. The membrane permeate was received by a beaker 407 mounted on an electronic balance 408, the amount of the membrane permeate was measured by the electronic balance 408, and the measured value was taken into the personal computer 409. Moreover, the presence or absence of pressurization of each part of the membrane filtration test apparatus was adjusted by opening and closing the valve 412, the valve 413, and the valve 414.

  First, a membrane filtration test using pure water was performed to measure the initial value of membrane filtration resistance. Here, the membrane filtration pressure was 20 kPa, and the stirring speed by the magnetic stirrer 403 was 600 rpm. Moreover, the measured value in the electronic balance 408 was taken into the personal computer 409 at intervals of 2 seconds. The membrane filtration test using pure water was conducted until an amount of 80 ml of membrane permeate was obtained.

  Next, a membrane filterability evaluation test using activated sludge was performed. First, the pure water chamber 410 was removed and the dotted line 415 in FIG. 12 was connected. 12 ml of activated sludge was put into the stirring type cell 401, the membrane filtration test was conducted at a membrane filtration pressure of 20 kPa and a stirring speed by the magnetic stirrer 403 of 600 rpm. The measured value in the electronic balance 408 was taken into the personal computer 409 at intervals of 2 seconds, and the membrane filtration test for 700 seconds was performed.

  The membrane filtration test was also performed using a centrifugal supernatant obtained by centrifugation (3500 rpm, 10 minutes).

  In each membrane filtration test described above, data indicating the relationship between the filtration time taken into the personal computer 409 and the amount of filtrate was processed as follows. First, the membrane filtration flux at any filtration time was calculated using the differential coefficient of the filtrate amount at any filtration time. Next, from the membrane filtration flux at the arbitrary filtration time, the membrane filtration resistance at the arbitrary filtration time was calculated according to the formula (1) using the membrane filtration pressure. From the results calculated as described above, a relationship between the total filtrate amount per unit membrane area and the membrane filtration resistance was created.

  From the relationship between the total filtrate volume per unit membrane area and the membrane filtration resistance created from the results of the membrane filtration test using pure water, the average value of the membrane filtration resistance in the section where the filtrate volume is 70 to 80 mL is calculated. The initial value was membrane filtration resistance.

  First, the result of the membrane filtration test using the centrifugal supernatant was predicted.

Supernatant component substance amount value P (0) = 289 at time zero, supernatant component substance amount value Pm (0) = 0 attached to the separation membrane, membrane filtration resistance initial value Rm = 8.5 × 10 ¹⁰ , Membrane cleaning power value τ = 10 (constant value), membrane filtrate viscosity μ = 1.0 × 10 ⁻³ , and transmembrane pressure difference value ΔP = 20 × 10 ³ were input. In addition, a resistance coefficient αp, a peeling coefficient γp, and a friction coefficient λp were input as parameters necessary for the membrane filtration program, and a membrane filtration prediction result was output. And the said membrane filtration prediction was repeatedly performed changing resistance coefficient (alpha) p, peeling coefficient (gamma) p, and friction coefficient (lambda) p so that the difference of a measured value and a membrane filtration prediction result might become the minimum. As a result, when the resistance coefficient αp = 1.32 × 10 ¹³ , the peeling coefficient γp = 2.6 × 10 ⁴ , and the friction coefficient λp = 4.2 × 10 ⁻⁵ , the actual measurement value and the membrane filtration prediction result are minimum. became.

Next, the results of the membrane filtration test using sludge were predicted.
Supernatant component substance amount value P (0) = 20.4 at time zero, solid component substance amount value X (0) = 1.731 × 10 ^{3 at} time zero, supernatant component substance amount adhering to the separation membrane Value Pm (0) = 0, solid component substance amount value Xm (0) = 0 adhering to the separation membrane, membrane filtration resistance initial value Rm = 8.5 × 10 ¹⁰ , membrane cleaning power value τ = 10 (constant) Value), the viscosity of the membrane filtrate μ = 1.0 × 10 ⁻³ , and the transmembrane pressure difference ΔP = 20 × 10 ³ . Further, as the parameters determined above, a resistance coefficient αp = 1.32 × 10 ¹³ , a peeling coefficient γp = 2.6 × 10 ⁴ , and a friction coefficient λp = 4.2 × 10 ⁻⁵ were input. In addition, a resistance coefficient αx, a peeling coefficient γx, and a friction coefficient λx were input as parameters necessary for the membrane filtration program, and a membrane filtration prediction result was output. And the said membrane filtration prediction was repeatedly performed changing resistance coefficient (alpha) x, peeling coefficient (gamma) x, and friction coefficient (lambda) x so that the difference of a measured value and a membrane filtration prediction result might become the minimum. As a result, when the resistance coefficient αx = 20 × 10 ¹⁰ , the peeling coefficient γx = 4.0 × 10 ³ , and the friction coefficient λx = 1.1 × 10 ⁻⁵ , the actual measurement value and the membrane filtration prediction result were minimized. .

In the prediction step 1, in order to predict fluctuations in the value of the membrane resistance, data (X: 1731 [gC / m ³ ], P: 24 [gC] representing the time-series change in the component amount of the liquid to be filtered. / M ³ ]), data representing time-series changes in membrane filtration flux (fixed data of 3.41 × 10 ⁻⁶ [m / s] as continuous filtration) Entered in the computer that has the formula in. As other data, the viscosity data of the membrane filtrate, the initial membrane resistance data of the separation membrane (Rm: 8.5 × 10 ¹⁰ [1 / m]), and the parameter values shown in Table 1 were input. In addition, a hypothetical film cleaning power value was temporarily set to 0.28 and entered into the computer. The fluctuation of the value of the membrane resistance was predicted using the input data of the component amount of the liquid to be filtered, the data of the membrane filtration flux, and the virtual value of the membrane cleaning power. The result is shown in FIG. With the passage of filtration time, the value of membrane resistance tended to diverge. Here, when the value of the membrane resistance diverges, it is determined that the value of the virtual membrane cleaning power is non-existent, and this value of the virtual membrane cleaning power is determined to be non-existent. Therefore, in the changing step 40, the value of the virtual film cleaning power is increased to 0.29. Then, in the prediction step 1 again, when the fluctuation of the value of the membrane resistance is predicted, the membrane resistance is decreased as a whole compared with the case where the value of the virtual membrane cleaning power is 0.28. The tendency of the resistance value to diverge was not changed (FIG. 7). Therefore, it was determined that this hypothetical membrane cleaning power value was non-existent. Therefore, in the change step 40 again, the value of the virtual membrane cleaning power is increased to 0.30 and the fluctuation of the value of the membrane resistance is predicted again. As a result, the membrane resistance converges and stabilizes to a constant value. (FIG. 7). Therefore, it was determined that the value of the virtual membrane cleaning power was right, and the appropriate value of the membrane cleaning power was determined to be 0.30.

  On the other hand, the following membrane filtration test was performed in order to obtain the relationship between the value of the aeration air volume, which is the power value of the cleaning means, and the value of the membrane cleaning power according to the calibration 210. As shown in FIG. 8, the membrane filtration device 500 has a structure in which a tube is connected to the filtrate side of the separation membrane 502, and the membrane filtrate can be obtained by a water head difference using the siphon principle. In addition, a flow meter 514 (digital type) is installed in the middle of the tube, and a change with time of the indicated value of the flow meter 514 can be continuously recorded on the recorder 515. In addition, a valve 516 is installed downstream of the flow meter 514 so that intermittent operation can be performed manually. The difference between the water level of the filtrate in the filtrate storage tank 501 and the height of the tube outlet of the membrane filtration test apparatus (see FIG. 8) was ΔH, and the membrane filtration pressure was calculated from ΔH.

  In such a membrane filtration apparatus, first, the amount of aeration was maintained at a constant flow rate of 300 L / min. ΔH was changed by changing the height of the tube outlet of the membrane filtration test apparatus over time, and membrane filtration was intermittently performed by opening and closing the valve 516 intermittently. The time-dependent change of the value of the membrane filtration pressure at that time is shown in FIG. Here, the value of the membrane filtration pressure is zero when the valve 516 is closed. Further, FIG. 10 shows the change with time of the value of the membrane filtration flow rate (indicated value of the flow meter 514) when the membrane filtration is continued. Further, the change with time of the membrane filtration flow rate under the condition of the membrane filtration pressure shown in FIG.

  In the prediction step 2, the equation (1 ′) is used as the calculation step 10 (where μ is the equation (2)), and the calculation step 20 is expressed by the equations (3) and (4). Each of them is used by substituting J = Q / A, and the equation (5) is used as the calculation step 30. Such a calculation was performed using the same calculation software and calculation method as in the prediction step 1.

  Although the prediction step 1 and the prediction step 2 have different inputs and outputs, the calculation formula itself used for the calculation is basically the same, and the target liquid to be filtered and the separation membrane are also the same. Therefore, the specification values shown in Table 1 are also the same, and it can be determined that the value of the film cleaning power used in the prediction step 1 is the same as the value of the film cleaning power used in the prediction step 2.

  Here, the integral value of the difference between the calculation result of the change over time of the value of the membrane filtration flow rate and the change over time of the actual value of the membrane filtration flow rate at an arbitrary virtual membrane cleaning power value is calculated. As a result of obtaining the minimum film cleaning power, it was 0.26. FIG. 10 shows the calculation result of the change over time in the value of the membrane filtration flow at that time together with the actual measurement value. It was confirmed that the measured values could be sufficiently reproduced except for an extreme increase in the value of the membrane filtration flow rate immediately after changing the value of the membrane filtration pressure. Thus, it was judged that the value of the membrane cleaning power when the aeration air volume was 300 L / min was 0.26.

  Similarly, when the aeration air volume was 400 L / min and the film detergency value when the aeration air volume was 500 L / min were evaluated, they were 0.30 and 0.33, respectively.

  From the above, the aeration air volume corresponding to the appropriate value 0.30 of the membrane cleaning power is 400 L / min. In the present invention, the appropriate value of the aeration air volume (that is, the appropriate power value of the cleaning means) is 400 L / min. Therefore, the value of the amount of aeration air from the aeration blower 503 serving as the cleaning means was set to 400 L / min.

(Example 2)
In Example 1, although the example in the case of continuous filtration was described, in Example 2, the example in the case of intermittent filtration is described.

Membrane filtration device, membrane resistance prediction method, membrane filtration test method, calculation software used, integration method, various specifications necessary for calculation, component component amount value of filtrate, and initial membrane resistance value are examples Same as 1. Here, as intermittent filtration conditions, intermittent filtration with a 2-minute rest for 8 minutes (the membrane filtration flux during suction is 4.26 × 10 ⁻⁶ [m / s]), that is, the membrane filtration flux 4.26 × The cycle of suction filtration at 10 ⁻⁶ [m / s] for 8 minutes and then stopping suction filtration for 2 minutes was repeated.

First, as in the first embodiment, in the prediction step 1, the fluctuation of the film resistance value is predicted. Here, using the equation (1) as the calculation step 10 (where μ uses the equation (2)), and using the equation (3) and the equation (4) as the calculation step 20, The equation (5) was used as the calculation step 30. Data representing time-series changes in the component amount of the liquid to be filtered (fixed data with X: 1731 [gC / m ³ ], P: 24 [gC / m ³ ]), time series of membrane filtration flux Data indicating a typical change (for intermittent filtration, the membrane filtration flux is 4.26 × 10 ⁻⁶ [m / s] for 8 minutes, and the membrane filtration flux is 0 [m / s] for the next 2 minutes. Repeated fluctuation data) is input into the computer in which the calculation formula in the prediction step 1 is incorporated. As other data, the data of the viscosity of the membrane filtrate, the data of the initial membrane resistance of the separation membrane (Rm: 8.5 × 10 ¹⁰ [1 / m]), and the parameter values described in Table 1 were input. In addition, a hypothetical film cleaning power value was temporarily set to 0.28 and entered into the computer. The fluctuation of the value of the membrane resistance was predicted using the inputted data of the component amount of the liquid to be filtered, the data of the membrane filtration flux, and the value of the virtual membrane cleaning power.

The result is shown in FIG. At the time of suction, the membrane resistance value increased with the passage of the filtration time, and at rest, the membrane resistance value tended to decrease. Here, when the membrane resistance is equal to or greater than a predetermined value, it is determined that the value is non-existent, and the predetermined value is set to 3.0 × 10 ¹² [1 / m from the maximum output value of the pump used in the membrane filtration device 500. ]. When the value of the virtual film cleaning power was 0.28, the value of the film resistance exceeded a predetermined value, so that this virtual film cleaning power was determined to be non-existent. Therefore, in the changing step 40, the virtual value of the film cleaning power is increased to 0.29. And when the fluctuation of the value of the membrane resistance was predicted again, the membrane resistance decreased as a whole compared with when the value of the virtual membrane cleaning power was 0.28, but the membrane resistance had a predetermined value. The trend of exceeding did not change (Figure 11). That is, it was determined that the value of this virtual film cleaning power was non-existent. Therefore, in change step 40 again, the value of the virtual film cleaning power is increased to 0.30. When the fluctuation of the membrane resistance value was predicted again under the membrane filtration conditions at this time, the membrane resistance value did not exceed the predetermined value (FIG. 11). Therefore, the appropriate value of the membrane cleaning power was determined to be 0.30.

  Here, from the relationship between the aeration air volume obtained by calibration in Example 1 and the value of the membrane cleaning power, the aeration air volume corresponding to the appropriate value of 0.30 for the membrane cleaning power is 400 L / min. Is determined that the appropriate value of the aeration air volume (that is, the appropriate value of the power of the cleaning means) is 400 L / min, and the value of the aeration air volume from the aeration blower 503 serving as the cleaning means is 400 L / min.

It is a flowchart in case the prediction step 1 is included in this invention. It is a flowchart in case the prediction step 2 is included in this invention. It is a flowchart in the case of including the prediction step 1 and using the change step 40 in this invention. It is a flowchart in the case of using the change step 40 including the prediction step 2 in this invention. It is an example of the implementation flowchart of this invention. 1 is a schematic diagram of a membrane filtration device used in Example 1. FIG. It is a figure which shows the time-sequential change of the value of the membrane resistance calculated in Example 1. FIG. 1 is a schematic diagram of a membrane filtration test apparatus performed in Example 1. FIG. It is a figure which shows the time-sequential change of the membrane filtration pressure of Example 1. FIG. It is a figure which shows the time-sequential change (actually measured value / calculated value) of the membrane filtration flux obtained in Example 1. FIG. It is a figure which shows the time-dependent change of the value of the film resistance calculated in Example 2. FIG. It is a figure of the membrane filtration test apparatus utilized in order to determine the factors for performing prediction in Example 1. FIG.

Explanation of symbols

400: Membrane filtration test apparatus 401: Stirring cell 402: Separation membrane 403: Magnetic stirrer 404: Stirring bar 405: Nitrogen gas 406: Membrane fixing holder 407: Beaker 408: Electronic scale 409: Personal computer 410: Pure water chamber 411: Pressure Total 412, 413, 414: Valve 500: Membrane filtration device 501: Filtration liquid storage tank 502: Separation membrane 503: Aeration blower 504: Filtration liquid 505: Membrane filtrate acquisition means 506: Raw water 507: Air diffuser 514: Flow rate Total 515: Record meter 516: Valve

Claims (16)

Using a membrane filtration apparatus having at least a separation membrane and a washing means for washing the surface of the separation membrane, the liquid to be filtered is filtered through the separation membrane, and the surface of the separation membrane is washed simultaneously or sequentially with the filtration. It is a method for determining the operating conditions of the membrane filtration device to be performed, from the data representing the time series change in the type and amount of the constituent components of the liquid to be filtered, and the data representing the time series change in the membrane filtration flow rate, Predicting fluctuations in the amount of constituent components adhering to the separation membrane, fluctuations in membrane filtration pressure, or fluctuations in membrane resistance, determining the power value of the cleaning means based on the prediction results, and the prediction, A calculation step for calculating the amount of the component adhering to the separation membrane based on the data representing the time-series change in the component amount of the filtrate and the data representing the time-series change in the membrane filtration flow rate. Including 100 or The calculation step 100 determines the amount of change in the amount of the component adhering to the separation membrane, the rate at which the substance contained in the component of the liquid to be filtered adheres to the separation membrane, and the rate at which the substance is separated from the separation membrane. The calculation step 101 is calculated based on a calculation expression expressed as a difference between the two, and the separation rate of the substance contained in the constituent components of the liquid to be filtered is attached to the separation membrane. A method for determining operating conditions of a membrane filtration device, including determining based on a quadratic expression of values of constituent component amounts.
Using a membrane filtration apparatus having at least a separation membrane and a washing means for washing the surface of the separation membrane, the liquid to be filtered is filtered through the separation membrane, and the surface of the separation membrane is washed simultaneously or sequentially with the filtration. It is a method for determining the operating conditions of the membrane filtration device to be performed, from the data representing the time series change in the type and amount of the constituent components of the liquid to be filtered, and the data representing the time series change in the membrane filtration pressure, Predict fluctuations in the amount of components adhering to the separation membrane, fluctuations in membrane filtration flow rate, fluctuations in membrane filtration flux, or fluctuations in membrane resistance, and determine the power value of the cleaning means based on the prediction results And the prediction is attached to the separation membrane based on data representing a time-series change in the component amount of the liquid to be filtered and data representing a time-series change in the membrane filtration pressure. Calculation step for calculating the component amount 100, and the calculation step 100 shows the amount of change in the amount of the component adhering to the separation membrane, the rate at which the substance contained in the component of the liquid to be filtered adheres to the separation membrane, and the separation membrane The calculation step 101 is calculated based on a calculation formula expressed as a difference from the separation rate from the separation membrane, and the separation rate of the substances contained in the constituent components of the liquid to be filtered is separated from the separation membrane. A method for determining the operating conditions of a membrane filtration device, comprising determining based on a quadratic expression of the value of the amount of component adhering to the membrane.
The method for determining the operating conditions of the membrane filtration device according to claim 1 or 2, wherein a supernatant component and / or a solid component of the liquid to be filtered is used as a kind of constituent components of the liquid to be filtered. The calculation formula expressing the amount of change in the amount of the supernatant component adhering to the separation membrane is a calculation formula including the term of the amount of the solid component adhering to the separation membrane. And / or the calculation expression expressing the amount of change in the amount of the solid component adhering to the separation membrane includes a term of the amount of the substance amount of the supernatant component adhering to the separation membrane. It is a calculation formula, The determination method of the operating condition of the membrane filtration apparatus of Claim 3 characterized by the above-mentioned. From the virtual membrane detergency value, change the amount of constituents adhering to the separation membrane, change in membrane filtration pressure, change in membrane filtration flow rate, change in membrane filtration flux, or change in membrane resistance. Predicting whether or not the value of the virtual film cleaning power is appropriate based on the prediction result, and determining the appropriate value of the film cleaning power from the value of the virtual film cleaning power determined to be good in the determination result The determination of the operating condition of the membrane filtration device according to any one of claims 1 to 4, wherein the power value of the cleaning means is determined based on the determined appropriate value of the membrane cleaning power. Method. In the determination result, when it is determined that the value of the virtual film cleaning power is not, after increasing the value of the virtual film cleaning power by a predetermined amount, from the value of the virtual film cleaning power again, Predicting fluctuations in the amount of constituents adhering to the separation membrane, fluctuations in membrane filtration pressure, fluctuations in membrane filtration flow rate, fluctuations in membrane filtration flux, or fluctuations in membrane resistance, based on the prediction results, When determining whether or not the value of the virtual film cleaning power after the predetermined amount is increased, and when determining that the value of the virtual film cleaning power is good in the determination result, the virtual film cleaning power 6. The method for determining operating conditions of a membrane filtration device according to claim 5, wherein the value of the cleaning power is set to an appropriate value of the membrane cleaning power. From the imaginary power value of the cleaning means, fluctuations in the amount of components adhering to the separation membrane, fluctuations in membrane filtration pressure, fluctuations in membrane filtration flow rate, fluctuations in membrane filtration flux, or fluctuations in membrane resistance Based on the prediction result, the power value of the virtual cleaning means is determined, and the cleaning means is determined from the power value of the virtual cleaning means determined to be good in the determination result. The membrane filtration according to any one of claims 1 to 4, wherein an appropriate value of the power of the cleaning means is determined, and a power value of the cleaning means is determined based on the determined appropriate value of the power of the cleaning means. Method for determining the operating conditions of the device. In the determination result, when it is determined that the power value of the virtual cleaning unit is not, the power value of the virtual cleaning unit is increased by a predetermined amount, and then the power of the virtual cleaning unit is increased again. From the value, the fluctuation of the amount of components adhering to the separation membrane, the fluctuation of the membrane filtration pressure, the fluctuation of the membrane filtration flow rate, the fluctuation of the membrane filtration flux, or the fluctuation of the membrane resistance is predicted, and the prediction result Based on determining whether the power value of the virtual cleaning means after the predetermined amount has increased, and in the determination result, when determining that the power value of the virtual cleaning means is good, The method for determining operating conditions of a membrane filtration device according to claim 7, wherein the virtual power value of the cleaning means is set to an appropriate value of power of the cleaning means. In the prediction result, the value of the component amount adhering to the separation membrane, the value of the membrane resistance or the value of the membrane filtration pressure is not more than a predetermined value, or the value of the membrane filtration flux or the membrane filtration flow rate. claims value when a predetermined or greater than a predetermined value, the virtual membrane washing force value, or, characterized in that to determine the power value of the virtual said cleaning means and Shi The determination method of the operating condition of the membrane filtration apparatus in any one of 6-8 . In the prediction result, when the value of the component amount adhering to the separation membrane, the value of the membrane resistance, or the value of the membrane filtration pressure converges, the value of the virtual membrane cleaning power, or the virtual value The method for determining operating conditions of a membrane filtration device according to any one of claims 6 to 8, wherein the power value of the cleaning means is determined to be good. After determining the proper value of the power of the cleaning means on the basis of the appropriate value of the film detergency claims, characterized in that determining the operating condition on the basis of the proper value of the power of the determined said cleaning means Item 11. A method for determining operating conditions of a membrane filtration device according to Item 5, 6, 9, or 10 . The value of the shearing force generated on the membrane surface or the value of the flow rate of the liquid to be filtered on the membrane surface with respect to the power value of the arbitrary cleaning means is obtained, and the value of the shearing force generated on the membrane surface or the value of the coating on the membrane surface is obtained. By determining the value of the membrane cleaning power based on the value of the flow rate of the filtrate, the relationship between the value of the membrane cleaning power and the power value of the cleaning means is obtained, and the appropriateness of the membrane cleaning power is determined based on the relationship. The method for determining the operating condition of the membrane filtration device according to claim 11, wherein an appropriate value of the power of the cleaning means is determined from the value. By determining the value of the membrane cleaning power relative to the power value of any of the cleaning means based on the result calibrated by the prediction method including the calculation step 100 or the calculation step 101, the value of the membrane cleaning power and the cleaning power 12. The membrane filtration device according to claim 11 , wherein a relationship with a power value of the means is obtained, and an appropriate value of the power of the cleaning means is determined from an appropriate value of the membrane cleaning power based on the relationship. How to determine operating conditions. Cleaning of the surface of the separation membrane, to aerating the membrane surface, it is fluidized to be filtered liquid, or according to any one of claims 1 to 13, characterized in that it is made by moving the separation membrane A method for determining the operating conditions of a membrane filtration device. The method for determining operating conditions of a membrane filtration device according to any one of claims 1 to 14, wherein the liquid to be filtered is a liquid containing microorganisms. A method for operating a membrane filtration device, comprising: controlling a power value of the cleaning means determined in the method for determining an operation condition for a membrane filtration device according to any one of claims 1 to 15 .

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