JP5435658B2 - Water quality simulation method and apparatus - Google Patents

Description

  The present invention relates to treatment of wastewater including industrial wastewater and factory wastewater, and more particularly, to a water quality simulation method and apparatus in a biological aerobic treatment process of wastewater containing compound components having biodegradability. This application claims priority on November 14, 2008 based on Japanese Patent Application No. 2008-292519 for which it applied to Japan, and uses the content here.

  In recent years, water quality regulations in closed water areas have been intensifying, and countermeasures for sewerage, industrial wastewater, and factory wastewater are urgently needed. In order to comply with the water quality regulation values, it is necessary to predict how much of which component can be processed to meet the standard. Until now, in the sewerage field, sewage treatment methods have been taken by biological treatment processes such as activated sludge process. The operation management is often performed mainly based on the experience of the manager, and it is difficult to obtain a stable treated water quality. For example, when the influent water quality fluctuates, the operation conditions and operation amount to be changed differ for each sewage treatment plant.

Therefore, an activated sludge model (ASM) proposed by IWA (International Water Association) has been proposed as a water quality prediction and operation support tool that does not depend on the experience of the manager. The activated sludge model consists of the following steps:
(1) The COD concentration of influent wastewater is fractionated according to the properties of soluble inert organic matter, readily decomposable organic matter, floating inert organic matter, slow decomposable organic matter, etc., and each is set as a COD concentration-based variable;
(2) For each process such as heterotrophic growth and autolysis, set stoichiometry between variables and the reaction rate equation of the process;
(3) Stoichiometric coefficients and reaction rate constant parameters are determined by oxygen consumption rate test or calibration from measured water quality data;
(4) A simulation is executed to calculate the biological treatment tank, the COD concentration of the treated water, and the like.

This activated sludge model has been proposed as a management tool, and a sewage treatment management system using the activated sludge model has been proposed (see Patent Document 1 below).
On the other hand, industrial wastewater and factory wastewater having components different from sewage are also treated by biological treatment processes. However, there is no case where the activated sludge model is applied to the water quality simulation method for these wastewaters.
In particular, the wastewater generated from the steelworks coke plant is called "ansui", which is mainly composed of phenol, thiosulfuric acid, and thiocyanic acid, but these are components not included in sewage, and the applicability of the activated sludge model. There are no cases examined.

JP 2003-300093 A

Shun Miso, activated sludge model, Japan, Environmental Newspaper Co., Ltd., January 31, 2005 J. et al. S. Cech, J. et al. Chudoba and P.M. Grau, Determination of Kinetic Constants of Activated Sludge Microorganisms, Water Science and Technology, Vol. 17, pp. 259-272, 1984

As described above, an activated sludge model is generally used as a water quality simulation method in biological aerobic treatment, but there is no example applied to biological aerobic treatment of industrial wastewater or factory wastewater. The following two points can be cited as the cause.
(1) The activated sludge model predicts only the COD concentration of influent wastewater and treated water when biologically aerobically treating wastewater mixed with multiple components such as sewage, but the concentration of biodegradable compound components Is unpredictable. For example, in the low water generated in the coke production process, phenol contained in the low water is one of the wastewater standard items, and it is necessary to predict the phenol concentration by simulation. Since it is difficult to predict the phenol concentration in treated water after biological aerobic treatment of wastewater mixed with multiple components, the significance of applying the activated sludge model to industrial wastewater and factory wastewater was small.
(2) Industrial wastewater and factory wastewater contain soluble and slowly decomposable organic substances (surfactants such as linear alkylbenzene sulfonic acid) or inorganic substances (such as thiosulfuric acid and thiocyanic acid). However, the municipal sewage targeted in the activated sludge model does not contain so much soluble slow-degrading components with very slow decomposition rate, and did not consider the influence on the oxygen balance of the model. That is, in the first place, the concept of a soluble and slow-degradable component was not included in the activated sludge model, so it was difficult to apply the activated sludge model to industrial wastewater or factory wastewater.

  Therefore, the present invention provides a new activated sludge model in a process for biologically aerobically treating wastewater such as industrial wastewater and factory wastewater containing compound components having biodegradability in a biological reaction tank, It is an object of the present invention to provide a water quality simulation method and apparatus capable of estimating how the concentration of the compound changes after biological aerobic treatment.

The present invention simulates a biological aerobic treatment process using an activated sludge model by fractionating each component in waste water and setting the type and variable of bacteria that decompose the component for each component and the reaction process. It is possible to determine the component concentration in the treated water, and even the wastewater containing soluble slow-decomposable components is fractionated for each component in the wastewater, so the concept of soluble slow-decomposable components should be used. The objective is to provide a water quality simulation method applicable to industrial and industrial wastewater containing biodegradable compound components, which enables simulation of biological aerobic treatment processes using activated sludge models And

｛式中、Ｃ_iは、各成分濃度であり、ｉは、各成分を表す通し番号であり、Ｐ_ijは、化学量論パラメーターであり、ｊは、各プロセスを表す通し番号であり、そしてρ_jは、反応速度式（反応速度式パラメーターを含む速度式）である。｝により、前記生物学的反応槽内で前記生物学的好気処理した後の処理水における各成分のＣＯＤ濃度を算出する計算工程と、
前記各成分濃度と、ＣＯＤ_Cr、ＣＯＤ_Mn及び理論的酸素消費量から選ばれる一つのＣＯＤ濃度との相関関係をもとに、当該算出された生物学的処理水の各成分のＣＯＤ濃度を、各成分濃度に換算する成分濃度換算工程とを、含み、
前記パラメーター設定工程は、
（ア）前記流入する廃水及び処理水において、事前に時系列的に別途採取したそれぞれの生物分解性を有する化合物成分濃度と溶存酸素濃度を用いて、キャリブレーションによって決定する方法、
（イ）前記各成分それぞれに対して、各成分単独で前記生物学的好気処理を行って連続的に溶存酸素濃度を測定し、当該測定値から酸素消費速度を算出し、当該算出された酸素消費速度のデータから決定する方法、のいずれかの方法を用いて、前記化学量論パラメーター及び前記反応速度式パラメーターを設定する工程であり、
前記廃水が、コークス製造工程で発生する安水であり、
前記化合物成分のうち、有機物成分はフェノール、並びに、無機物成分はチオ硫酸及びチオシアン酸であり、
チオ硫酸、チオシアン酸のシミュレーションについては、
前記ＣＯＤ換算工程の代わりに、チオ硫酸及びチオシアン酸濃度を硫黄換算する硫黄換算工程と、
前記生物学的反応槽で上記生物学的好気処理した後の処理水における各成分の硫黄濃度を算出する硫黄計算工程と、
当該算出された生物学的処理水の各成分の硫黄濃度を、チオ硫酸濃度及びチオシアン酸濃度に再換算する硫黄再換算工程と
を採用する、水質シミュレーション方法。 The present invention specifically includes the following [1] and [2] :
[1] A water quality simulation method in a process of biologically aerobically treating wastewater containing a compound component having biodegradability in a biological reaction tank,
An analysis step of analyzing each component concentration of the compound component in the wastewater flowing into the biological reaction tank;
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, COD conversion that converts the analysis value of each component concentration into the COD concentration of each component Process,
A parameter setting step for setting the growth yield as a stoichiometric parameter, the saturation constant as a reaction rate equation parameter, the maximum specific growth rate, and the type and concentration of bacteria that degrade the compound components;
A dissolved oxygen concentration measuring step for measuring a dissolved oxygen concentration in the biological reaction tank;
Using the COD concentration of each component, the growth yield, the saturation constant, the maximum specific growth rate, the seed and concentration of bacteria that decomposes the compound component, and the dissolved oxygen concentration, the following equation (1) :

{Where C _i is the concentration of each component, i is the serial number representing each component, P _ij is the stoichiometric parameter, j is the serial number representing each process, and ρ _j Is a reaction rate equation (a rate equation including a reaction rate equation parameter). } To calculate the COD concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank,
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, the calculated COD concentration of each component of the biologically treated water is calculated as follows: a component concentration conversion step of converting the concentration of each component, seen including,
The parameter setting step includes
(A) A method of determining by calibration using the biodegradable compound component concentration and the dissolved oxygen concentration separately collected in advance in time series in the inflowing wastewater and treated water,
(B) For each of the components, the biological aerobic treatment is performed for each component alone to continuously measure the dissolved oxygen concentration, and the oxygen consumption rate is calculated from the measured value. A step of setting the stoichiometric parameter and the reaction rate equation parameter using any one of the methods of determining from oxygen consumption rate data,
The waste water is a safe water generated in the coke production process,
Among the compound components, the organic component is phenol, and the inorganic component is thiosulfuric acid and thiocyanic acid,
For simulations of thiosulfuric acid and thiocyanic acid,
Instead of the COD conversion step, a sulfur conversion step of converting the thiosulfuric acid and thiocyanic acid concentrations into sulfur,
A sulfur calculation step for calculating the sulfur concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank;
A sulfur reconversion step for reconverting the calculated sulfur concentration of each component of biologically treated water into a thiosulfuric acid concentration and a thiocyanic acid concentration;
Water quality simulation method that adopts

｛式中、Ｃ_iは、各成分濃度であり、ｉは、各成分を表す通し番号であり、Ｐ_ijは、化学量論パラメーターであり、ｊは、各プロセスを表す通し番号であり、そしてρ_jは、反応速度式（反応速度式パラメーターを含む速度式）である。｝により、前記生物学的反応槽で前記生物学的好気処理した後の処理水における各成分のＣＯＤ濃度を算出する計算手段と、
前記各成分濃度と、ＣＯＤ_Cr、ＣＯＤ_Mn及び理論的酸素消費量から選ばれる一つのＣＯＤ濃度との相関関係をもとに、当該算出された生物学的処理水の各成分のＣＯＤ濃度を、各成分濃度に換算する成分濃度換算手段と
を、含み、
前記パラメーター設定手段は、
（ア）前記流入する廃水及び処理水において、事前に時系列的に別途採取したそれぞれの生物分解性を有する化合物成分濃度と溶存酸素濃度を用いて、キャリブレーションによって決定する手段、
（イ）前記各成分それぞれに対して、各成分単独で前記生物学的好気処理を行って連続的に溶存酸素濃度を測定し、当該測定値から酸素消費速度を算出し、当該算出された酸素消費速度のデータから決定する手段、のいずれかの手段を用いて、前記化学量論パラメーター及び前記反応速度式パラメーターを設定する手段であり、
前記廃水が、コークス製造工程で発生する安水であり、
前記化合物成分のうち、有機物成分はフェノール、並びに、無機物成分はチオ硫酸及びチオシアン酸であり、
チオ硫酸、チオシアン酸のシミュレーションについては、
前記ＣＯＤ換算手段の代わりにチオ硫酸及びチオシアン酸濃度を硫黄換算する硫黄換算手段と、
前記生物学的反応槽で上記生物学的好気処理した後の処理水における各成分の硫黄濃度を算出する硫黄計算手段と、
当該算出された生物学的処理水の各成分の硫黄濃度を、チオ硫酸濃度及びチオシアン酸濃度に再換算する硫黄再換算手段と
を採用する、水質シミュレーション装置。 [ 2 ] A water quality simulation apparatus used in a process of biologically aerobically treating wastewater containing a compound component having biodegradability in a biological reaction tank,
Analyzing means for analyzing each component concentration of the compound component in the wastewater flowing into the biological reaction tank;
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, COD conversion that converts the analysis value of each component concentration into the COD concentration of each component Means,
Parameter setting means for setting the growth yield as a stoichiometric parameter, the saturation constant as a reaction rate equation parameter, the maximum specific growth rate, and the type and concentration of bacteria that degrade the compound components;
A dissolved oxygen concentration measuring means for measuring a dissolved oxygen concentration in the biological reaction tank;
Using the COD concentration of each component, the growth yield, the saturation constant, the maximum specific growth rate, the type and concentration of bacteria that degrade the compound component, and the dissolved oxygen concentration, the following equation (1):

{Where C _i is the concentration of each component, i is the serial number representing each component, P _ij is the stoichiometric parameter, j is the serial number representing each process, and ρ _j Is a reaction rate equation (a rate equation including a reaction rate equation parameter). }, The calculation means for calculating the COD concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank,
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, the calculated COD concentration of each component of the biologically treated water is calculated as follows: Component concentration conversion means for converting to each component concentration
Including,
The parameter setting means includes
(A) Means for determining by calibration using each biodegradable compound component concentration and dissolved oxygen concentration separately collected in advance in time series in the inflowing wastewater and treated water,
(B) For each of the components, the biological aerobic treatment is performed for each component alone to continuously measure the dissolved oxygen concentration, and the oxygen consumption rate is calculated from the measured value. Means for setting the stoichiometric parameter and the reaction rate equation parameter using any one of means for determining from oxygen consumption rate data,
The waste water is a safe water generated in the coke production process,
Among the compound components, the organic component is phenol, and the inorganic component is thiosulfuric acid and thiocyanic acid,
For simulations of thiosulfuric acid and thiocyanic acid,
Sulfur conversion means for converting thiosulfuric acid and thiocyanic acid concentrations into sulfur instead of the COD conversion means;
Sulfur calculating means for calculating the sulfur concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank;
A sulfur reconverting means for reconverting the calculated sulfur concentration of each component of biologically treated water into a thiosulfuric acid concentration and a thiocyanic acid concentration;
Water quality simulation device that adopts .

The effects produced by the present invention are as follows.
The concentration of each component in treated water can be predicted by converting the concentration of each component in the influent wastewater to COD concentration and applying the activated sludge model to industrial wastewater and factory wastewater containing biodegradable compound components. . In addition, regarding the soluble slow-degrading components that were not included in the activated sludge model, the component concentration of the treated water can be calculated by setting the type of bacteria that decomposes the components. Further, the concentration of each component, COD _Cr, when determining the correlation between a COD concentration selected from COD _Mn and theoretical oxygen consumption, since it is possible to use the analysis results of the COD _Mn, the COD _Cr Thus, analysis using dangerous and harmful chemicals may not be performed.

It is a block diagram which shows the water quality simulation method of the biological treatment process of wastewater based on this invention. It is a figure which shows the correlation of a phenol concentration and COD _Mn . It is a figure which shows the correlation of thiosulfuric acid concentration and COD _Mn . It is a figure which shows the correlation of a thiocyanic acid density | concentration and COD _Mn . It is a block diagram of an oxygen consumption rate test apparatus. It is a figure which shows the simulation result in Example 1 which concerns on this invention. It is a figure which shows the simulation result in Example 2 which concerns on this invention. It is a figure which shows the simulation result in Example 3 which concerns on this invention.

The components contained in the wastewater are divided into floating components that are not soluble in water and soluble components. For example, separation is performed using, for example, filter paper, so that what remains on the filter paper is obtained as a floating component and the filtrate is obtained as a soluble component. The present invention is a simulation method for biodegradation of a soluble component that is closely related to biodegradation. Since suspended components are hardly biodegraded and are finally removed by sedimentation separation, they are excluded from the scope of the present invention.
The soluble component is divided into a biodegradable component and a hardly degradable component that has little biodegradability. The hardly decomposable component is originally difficult to biodegrade and has a small concentration. Furthermore, the biodegradable component includes unknown components that are difficult to qualitatively and quantitatively analyzed. However, the biodegradable component may be ignored because it is a small amount of wastewater. For example, in an aqueous solution, components other than phenol, thiosulfuric acid, and thiocyanic acid correspond to this. From the above, it is possible to predict the compound component having biodegradability of the present invention even if the hardly decomposable component and the unknown component in the wastewater are ignored.
FIG. 1 is a diagram illustrating a flow of a wastewater quality simulation method according to the present invention. In addition, each “process” in the figure can be replaced with each “means”, and is also a diagram illustrating a water quality simulation apparatus for wastewater.

  Here, as an example of the waste water, the low water generated from the coke factory in the steelworks is shown as an example. The present invention can be applied to industrial waste water such as industry and dyeing industry and factory waste water as long as it contains a biodegradable compound component. For example, the water contains phenol as an organic component having biodegradability and thiosulfuric acid and thiocyanic acid as inorganic components.

Moreover, the treated water of FIG. 1 is the outflow water after a biological aerobic process in the case of a continuous process, and the water in a tank after predetermined time progress in the case of a batch process.
In addition, biological aerobic treatment means that a substrate and bacteria are present by mixing and stirring while supplying dissolved oxygen by aeration in a reaction tank having an aeration apparatus. This is a method for decomposing a substrate by contacting and reacting with.

  As shown in FIG. 1, the water quality simulation method 1 according to the present invention includes an analysis step 2 for analyzing the component concentration of industrial wastewater and factory wastewater flowing into a biological aerobic treatment process, and the concentration of each component and COD. COD conversion step 4 that converts each component to COD concentration 9 using correlation 3, and decomposes the stoichiometric parameters (growth yield) and reaction rate equation parameters (saturation constant and maximum specific growth rate), and compound components Using parameter setting step 6 for setting parameter 5 of the type and concentration of bacteria to be performed, dissolved oxygen concentration measuring step 8 for measuring dissolved oxygen concentration 7 in the biological reaction tank, parameter 5, dissolved oxygen concentration 7 and COD concentration 9 Thus, the calculation step 10 for calculating the COD concentration 11 of each component of biologically treated water by the above-described arithmetic expression (1), and the correlation between each component concentration and the COD concentration 3 using by a COD concentration 11 of each component is converted back to the concentration of each component, and a component concentration conversion step 12 of calculating the concentration of each component 13 of the treated water.

  The analysis step 2 does not specify a method for analyzing the component concentration, but it is desirable to use the same analysis method every time. For example, the phenol concentration can be analyzed by JIS K0102 spectrophotometry, the thiosulfuric acid and thiocyanic acid concentrations can be analyzed by ion chromatography, and the MLSS concentration can be analyzed by Non-Patent Document 1 described above.

を用いて、それぞれ、２．３８ｍｇ、０．５７ｍｇ、１．１ｍｇと算出される。Correlation 3 is obtained from each component concentration and COD concentration. As an example, FIGS. 2A to 2C show correlations based on measured values of phenol concentration, thiosulfuric acid, thiocyanic acid and COD _Mn concentration. As a result, the oxygen consumption per 1 mg of phenol, thiosulfuric acid, and thiocyanic acid was 2.1 mg, 0.48 mg, and 1.0 mg, respectively. Moreover, when calculating | requiring a correlation, it is desirable to use any analysis method of the same COD _Cr or COD _Mn as the method of measuring COD density | concentration at the analysis process, and the analysis method uses the same method consistently.

Thus, the known component concentrations, when determining the correlation between the COD concentration without using a _{COD Cr,} it is possible to use the analysis results of the _{COD Mn,} risk and hazard as _{COD Cr} There is an advantage that it is not necessary to perform analysis using a certain chemical.
In addition, as a method for easily obtaining the correlation between the concentration of each component and the COD concentration, there is a method of calculating the theoretical oxygen consumption of the component from the chemical reaction equation. For example, the theoretical oxygen consumption per mg of phenol, thiosulfuric acid and thiocyanic acid is expressed by the following chemical reaction formulas (1) to (3):

Are calculated as 2.38 mg, 0.57 mg, and 1.1 mg, respectively.

  The COD conversion step 4 converts each component concentration obtained in the analysis step 2 into a COD concentration by using the correlation 3. Here, the COD concentration is converted because it is adopted as the most excellent scale in the activated sludge model. That is, as described in Non-Patent Document 1, there is an advantage that the relationship between a series of electron equivalents such as organic matter, organisms, or oxygen used can be expressed only by COD, and an oxygen balance can be obtained. is there. Although it is possible to calculate each component concentration without converting to the COD concentration, it is not practical because the above-mentioned advantages cannot be utilized.

  Sulfur compounds such as thiosulfuric acid and thiocyanic acid can be converted into sulfur here for simulation and reconverted to each component concentration in the component concentration conversion step 12 described later. Thus, by separately considering thiosulfuric acid and thiocyanic acid as sulfur components, it is possible to calculate sulfate ion components that are not counted as COD. Thereby, it becomes possible to trace the mass balance of sulfur, and the behavior of the sulfur component can be grasped. However, even if the sulfur material balance is obtained by converting to sulfur, the oxygen material balance is obtained, so that the simulation is not affected. Bacteria that degrade sulfur compounds are generally considered to be sulfur-oxidizing bacteria, and unlike heterotrophic bacteria that degrade organic matter, they are thought to not interact with each other. The accuracy can be improved by considering separately from other components. In that case, the sulfur conversion values of 1 mg of thiosulfuric acid and thiocyanic acid are calculated as 0.57 mg and 0.55 mg from the chemical reaction formulas (2) to (3), respectively.

Further, the conversion from the component concentration to the COD is made the same as the component concentration conversion step 12 described later by consistently using any one of the theoretical oxygen consumption, COD _{Cr and} COD _Mn .
As parameter 5, the growth yield and stoichiometric parameter of each component, the saturation constant as the reaction rate equation parameter, the maximum specific growth rate, and the type and concentration of bacteria that degrade the compound component are used.
In addition, in order to take into account the effect of self-degradation of the organism itself in biological treatment, the specific endogenous respiration rate of the organism under aerobic conditions may be set as the reaction rate parameter, but usually the effect is small, It is not necessary to set.

The parameter setting step 6 can be broadly divided into (A) a method of performing an experiment and analyzing experimental data under a certain condition, and (B) a method of picking up literature values. It is preferable to set the parameter by the former. .
The method (A) will be described below. This method is (a) a method of determining by calibration using each biodegradable compound component concentration and dissolved oxygen concentration separately collected in advance in time series in the influent wastewater and treated water, (B) For each of the components, the biological aerobic treatment is performed for each component alone to continuously measure the dissolved oxygen concentration, and the oxygen consumption rate is calculated from the measured value. Of the methods determined from the oxygen consumption rate data, either (a) or (b) is used to set parameters in advance.

  For the time series measured value data of (a) above, a specific data acquisition method is not specified, but time series data is collected so that the density change can be understood. For example, when simulating the quality of treated water for one week, it is desirable to acquire data at three or more points in the meantime, for example, when two days, four days, and six days have elapsed. In addition, it is desirable that the time-series measured value data is stable. For example, in the case described above, data in which the concentration and composition of the inflowing water is greatly fluctuating during one week is not desirable. For example, when the accuracy of the simulation prediction is set within ± 5%, the fluctuation range of the concentration of components of the cold water flowing in at the time interval of the simulation biological treatment time (residence time) is 5%. Can be used.

｛式中、χ²（ｐ）は、対象とするモデルパラメーターｐのχ²の値であり、ｙ_meas,mは、ｍ番目の時系列データの実測値（成分濃度または酸素消費速度）であり、ｙ_m（ｐ）は、モデルパラメーターｐの値を仮定した時の、ｍ番目の時系列データの計算値（成分濃度または酸素消費速度）であり、σ_meas,mは、ｍ番目の時系列データの実測値の標準偏差又は実測値全体の標準偏差であり、そしてｎは、データポイントの数である。｝によりχ²の値を求め、χ²の値が最小となったときのパラメーターの値を用いる方法がある。パラメーターの値を求める方法は特に指定しないが、シンプレックス法、モンテカルロ法、遺伝的アルゴリズム等の数値解析手法によるものが望ましい。The method of determining by the calibration in (a) is not particularly specified. For example, the commercially available simulation software AQUASIM is used to calculate the following formula (2) from the time series measured value, the calculated value, and the standard deviation of the time series measured value. :

{Where χ ² (p) is the value of χ ² of the target model parameter p, and y _{meas, m} is the actual measurement value (component concentration or oxygen consumption rate) of the m-th time series data , Y _m (p) is the calculated value (component concentration or oxygen consumption rate) of the m th time series data assuming the value of the model parameter p, and σ _{meas, m} is the m th time series The standard deviation of the measured value of the data or the standard deviation of the entire measured value, and n is the number of data points. } To obtain the value of χ ² and use the parameter value when the value of χ ² is minimized. The method for obtaining the parameter value is not specified, but a numerical analysis method such as a simplex method, a Monte Carlo method, or a genetic algorithm is preferable.

  The method for determining parameters from the oxygen consumption rate data of the oxygen consumption rate test (b) above uses the test apparatus of FIG. In FIG. 3, the microbial sludge 22 used in the biological treatment process and the nitrification inhibitor 23 are added to the oxygen consumption rate test apparatus 21 to suppress oxygen consumption when ammoniacal nitrogen is nitrified to nitrate nitrogen. The liquid of the oxygen consumption rate test device 21 is mixed by the stirring device 24. Nutrient salt 25 may be added to prevent a decrease in the activity of microorganisms due to lack of nutrient salt. Next, the target component 26 is added to the oxygen consumption rate test apparatus 21, and the change over time in the dissolved oxygen concentration is measured by the dissolved oxygen concentration meter 27. Recording of the dissolved oxygen concentration may be performed by the data recording device 28. In order to control the dissolved oxygen concentration to a certain level or higher during the measurement, air may be supplied by the air supply device 29 when it falls below the control value. In order to control the pH to be constant, the pH may be measured by the pH meter 30, and the acid or alkali may be supplied by the acid / alkali supply device 31 for control. In order to control the temperature of the oxygen consumption rate test apparatus 21, a constant temperature water tank 33 provided with a heater 32 may be used.

｛式中、Ｙ_Aは、成分Ａを分解する細菌の増殖収率であり、Ｓ_A,CODは、成分ＡのＣＯＤ換算濃度であり、そしてＯ_2measは、酸素消費量の実測値である。｝によって求めることができる。A method for determining parameters from the change over time in dissolved oxygen concentration and oxygen consumption rate obtained by adding the target component (hereinafter referred to as component A) is not specified. From the COD equivalent concentration of A and the oxygen consumption, the following equation (3):

{ _Where Y _A is the growth yield of bacteria that degrade component A, S _{A, COD} is the COD equivalent concentration of component A, and O _2meas is the measured value of oxygen consumption. }.

  The method of obtaining the growth yield more precisely is to obtain the oxygen consumption rate by endogenous breathing in advance, and subtract the oxygen consumption rate by endogenous breathing from the measured value of the above oxygen consumption to obtain the oxygen used for growth. Although the consumption speed can be obtained, the method is not specified in the present invention.

｛式中、μ_Aは、成分Ａを分解する細菌の比増殖速度であり、Ｙ_Aは、成分Ａを分解する細菌の増殖収率であり、そしてｒ_OXは、比基質酸化速度である。｝に示す関係が成り立つ。Although the method for determining the maximum specific growth rate and the value of the saturation constant is not particularly specified, for example, it can be obtained by the method described in Non-Patent Document 2 described above. That is, after microbial sludge used in the oxygen consumption rate test is aerated for 1 hour, the microbial sludge is mixed with waste water at various dilution rates, and the oxygen consumption rate is measured. During measurement, control with aeration is performed to keep the dissolved oxygen concentration constant. Next, the specific oxygen consumption rate is obtained by dividing the measured oxygen consumption rate by the sludge concentration, and the specific oxygen consumption rate minus the oxygen consumption rate due to endogenous respiration (specific substrate oxidation rate) is obtained. The specific endogenous respiration rate is the oxygen consumption rate due to endogenous respiration during self-degradation of the organism itself, and is obtained from the oxygen consumption rate when the component A is not added in the oxygen consumption rate test. Desired. At this time, between the specific growth rate and the specific substrate oxidation rate, the following equation (4):

{Wherein μ _A is the specific growth rate of bacteria that degrade component A, Y _A is the growth yield of bacteria that degrade component A, and r _OX is the specific substrate oxidation rate. } Is established.

｛式中、μ_A,maxは、成分Ａを分解する細菌の最大比増殖速度であり、Ｋ_Aは、成分ＡのＣＯＤ濃度に対する飽和定数であり、Ｓ_A,CODは、成分ＡのＣＯＤ換算濃度であり、Ｓ_O2は、溶存酸素濃度であり、そしてＫ_O2は、溶存酸素濃度に対する飽和定数である。｝に示すミカエリス−メンテン式が成り立つ。On the other hand, between the specific growth rate mu _A and the maximum specific growth rate mu _{A, max,} the following arithmetic expression (5):

{Wherein, mu _{A, max} is the maximum specific growth rate of the bacteria degrade components A, K _A is the saturation constant for COD concentration of the component A, S _{A, COD} is COD Conversion Component A Is the concentration, S _O2 is the dissolved oxygen concentration, and K _O2 is the saturation constant for the dissolved oxygen concentration. } The Michaelis-Menten equation is established.

Here, in the oxygen consumption rate test, since the dissolved oxygen concentration is maintained at a high concentration, the value of S _O2 / (K _O2 + S _O2 ) can be regarded as approximately 1. Therefore, the specific growth rate can be regarded as a function of only the component concentration. Thus, a plot of the values and component concentration of the obtained specific growth rate mu _A by computing equation (4) is obtained by fitting the equation of arithmetic expression (5) to the plot, the maximum ratio of microbial growth The rate and saturation constant for component A are determined.

｛式中、ＯＵＲは、酸素消費速度であり、そしてＸ_Aは、成分Ａを分解する細菌の濃度であり、そしてＹ_Aは、成分Ａを分解する細菌の増殖収率であり、Ｋ_Ａは、成分Ａ濃度のＣＯＤ換算値に対する飽和定数であり、Ｓ_Aは、成分ＡのＣＯＤ換算濃度であり、Ｋ_O2は、溶存酸素濃度に対する飽和定数であり、Ｓ_O2は、溶存酸素濃度である。｝で表されることが多く、この式を用いる方法がある。The method for determining the type and concentration of bacteria that degrade the compound component is not particularly specified, but for the type, it is basically desirable that one type of bacteria corresponds to the degradation for one component. Furthermore, if there is a possibility that one type of bacteria can decompose multiple components based on experimental data or knowledge in the literature, one type of bacteria for multiple components can be used to improve calculation prediction in accordance with actual phenomena and calculation prediction accuracy. May be set to correspond. However, multiple types of bacteria may decompose one component, but they often show similar degradation effects, and the amount of calculation increases by increasing the number of types of bacteria. It is desirable to correspond to one kind of bacteria. Regarding the concentration of bacteria, the oxygen consumption rate using the compound component is expressed by the following equation (6):

{Where OUR is the rate of oxygen consumption, X _A is the concentration of bacteria that degrade component A, and Y _A is the growth yield of bacteria that degrade component A, and K _A is , S _A is the COD equivalent concentration of component A, K _O2 is the saturation constant relative to the dissolved oxygen concentration, and S _O2 is the dissolved oxygen concentration. }, And there is a method using this formula.

That is, in Equation (6), the maximum specific growth rate and the saturation constant for component A are determined by the above-described method. In the oxygen consumption rate test, the dissolved oxygen concentration is maintained at a high concentration, so that S _O2 / (K _O2 The value of + S _O2 ) can be regarded as almost 1. From this, the oxygen consumption rate is expressed only as a function of the concentration of bacteria that degrade component A. Accordingly, the arithmetic expression (6), by substituting OUR measured values obtained by the oxygen consumption rate test, it is possible to determine the X _A.

  With respect to the method for picking up the literature value of (B) above, for example, typical parameter values are described in Non-Patent Literature 1 described above, and the yield of heterotrophic organisms under aerobic conditions is 0.63. Has been. Although this value may be set as a parameter value, the value may be different depending on the target wastewater. Therefore, it is preferable to set it by the method (A) as much as possible.

  The dissolved oxygen concentration 7 is a method using a value obtained by measuring a dissolved oxygen concentration in a biological reaction tank by installing a dissolved oxygen concentration meter in a biological treatment process, or treating the dissolved oxygen concentration as a parameter in the parameter setting step 6, Any method using values determined by calibration may be used.

  The calculation process 10 calculates | requires the COD density | concentration 11 of each component of treated water using the COD density | concentration 9, the dissolved oxygen concentration 7, and the parameter 5. FIG. As a model used for the calculation, the COD concentration 11 of each component of the treated water is calculated by the above-described arithmetic expression (1) based on the IWA activated sludge model. The COD concentration 11 of each component of the treated water can be converted back to the component concentration value 13 of each component of the treated water by using the correlation 3 in the component concentration conversion step 12.

｛式中、Ｘ_Ａは成分Ａを分解する細菌の濃度であり、そしてＰ_Ａは成分Ａを分解するプロセスにおける化学量論パラメーターであり、そしてρ_Ａは成分Ａを分解するプロセスにおける反応速度論パラメーターであり、そしてｂはＸ_Ａが自己分解するときの比内生呼吸速度定数である。｝によって求めることができる。Further, in the calculation step 10, a simulation including the influence of pH, alkalinity, ammonia concentration and the like may be performed. Although the calculation method is not specified, for example, hydrogen ion concentration, dissolved carbon dioxide concentration, ammonia concentration, etc. are added to C _i, and stoichiometric parameters such as hydrogen ion concentration, dissolved carbon dioxide concentration, ammonia concentration, etc. are added to P _ij , And the reaction rate equation may be added to ρ _j for the calculation. In addition, in order to improve the prediction accuracy by taking into account the effects of self-degradation of the organism itself in biological treatment, the specific endogenous respiration rate of the organism under aerobic conditions may be set as the reaction rate parameter. Does not need to be set because it has little effect. When setting, the following equation (7):

{Wherein, X _A is the concentration of bacteria that degrade components A, and P _A is the stoichiometric parameters in the process of decomposing the component A, and [rho _A reaction kinetics in decomposing process component A it is a parameter, and b is the ratio internal raw respiration rate constant when X _a has autolyzed. }.

Example 1: Simulation of batch test for phenol, thiosulfuric acid, and thiocyanic acid (when one kind of bacteria decomposes one component)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration and calculation flow of a water quality simulation method for a biological treatment process.
Hereinafter, a simulation method of a batch test for phenol, thiosulfuric acid, and thiocyanic acid as biodegradable compound components will be described. In the batch test, components were added to a 1 L reaction vessel so that the phenol concentration was 100 mg / L, the thiosulfate concentration was 100 mg / L, and the thiocyanate concentration was 10 mg / L, and the MLSS concentration was 5000 mg / L. During the test, the dissolved oxygen concentration was measured with a dissolved oxygen concentration meter, and the pH was measured with a pH meter. The dissolved oxygen concentration was controlled to 3.25 mg / L and pH 7.5.

The analysis step 2 is a step of analyzing the component concentration in the wastewater flowing into the biological treatment process. Here, the analysis step 2 is the initial component concentration in the batch test apparatus, and is calculated from the amount of each component added. The phenol concentration was confirmed by JIS K0102 absorptiometry, the thiosulfuric acid and thiocyanic acid concentrations were confirmed by ion chromatography analysis, and the MLSS concentration was confirmed by the centrifugation method described in Non-Patent Document 1 described above. The COD conversion step 4 is a COD conversion step of converting the concentrations of phenol, thiosulfuric acid, and thiocyanic acid obtained in the analysis step 2 into COD concentrations. For COD conversion, conversion is performed according to the correlation 3 between the phenol concentration, thiosulfuric acid concentration and thiocyanic acid concentration and COD _Mn concentration shown in FIGS. 2A to 2C, and the concentrations of phenol, thiosulfuric acid, and thiocyanic acid are calculated. The COD concentration of each component was converted to 11.

In the parameter setting step 6, the parameters used in the calculation step 10 were set.
For parameter 5, the growth yield, the maximum specific growth rate, the saturation constant, and the concentration of phenol-degrading bacteria, concentration of thiosulfate-degrading bacteria, and concentration of thiocyanate-degrading bacteria used in calculation step 10 described later were set. As a result of examining the method of determining from the oxygen consumption rate data of the oxygen consumption rate test and the method by calibration, both of the setting methods obtained reasonable values, but in this case they were obtained from the oxygen consumption rate test. Since some variation was found in the parameter values obtained, the method by calibration was used. A commercially available simulation software AQUASIM was used for calibration. Specifically, the value of χ ² shown in the calculation formula (2) is obtained from the measured value, the calculated value, and the standard deviation of the measured value, and the parameter value when the value of χ ² is minimized is calculated. . The actual measurement value was obtained by changing the component concentration with time from a batch test for each component performed in advance. The calculated value was obtained by the method of calculation step 10 described later.

As the dissolved oxygen concentration 7, a control value of 3.25 mg / L in the batch test was used.
The calculation step 10 uses the COD concentration 9 of each component of the wastewater, the dissolved oxygen concentration 7 and the parameter 5 to simulate the time-dependent changes in the phenol, thiosulfuric acid, and thiocyanic acid concentrations in the batch test. A COD concentration of 11 was determined. As the calculation method, the arithmetic expression (1) was used. Table 1 below shows each component concentration C _i , stoichiometric parameter, and reaction rate parameter used in the calculation.

Table 2 below shows the stoichiometric relationship in process ρ _j , for example, in the growth of phenol-degrading bacteria in process ρ ₁ , P ₁₁ = −1 / Y for phenol-degrading bacteria (X _Phe ). _The phenol concentration changes with the ratio of _Phe , and S _O2 changes with the ratio of P ₄₁ = − (1-Y _Phe ) / Y _Phe .

Table 3 below shows the reaction rate equation used for the calculation.

｛式中、Ｓ_Pheは、フェノール濃度であり、ｔは、時間であり、Ｓ_O2は、溶存酸素濃度であり、Ｋ_O2は、溶存酸素濃度に対する飽和定数であり、Ｋ_Pheは、フェノール濃度に対する飽和定数であり、Ｘ_Pheは、フェノール分解細菌濃度であり、そしてμ_Pheは、フェノール分解細菌の最大比増殖速度であり、Ｙ_Pheは、フェノール分解細菌の増殖収率である。｝で表される。For example, in the growth of phenol-degrading bacteria in process ρ _1, the rate of increase in phenol concentration is expressed by the following equation (7):

{ _Wherein S _Phe is the phenol concentration, t is the time, S _O2 is the dissolved oxygen concentration, K _O2 is the saturation constant for the dissolved oxygen concentration, and K _Phe is the phenol concentration. Saturation constant, X _Phe is the concentration of phenol-degrading bacteria, μ _Phe is the maximum specific growth rate of phenol-degrading bacteria, and Y _Phe is the growth yield of phenol-degrading bacteria. }.

  Similarly to the COD conversion step 4, the component concentration conversion step 12 sets each component COD concentration 11 of the treated water according to the correlation 3 between the phenol, thiosulfuric acid, and thiocyanic acid concentrations shown in FIGS. 2A to 2C and the COD concentration. Reconverted to component concentration.

  The result of the above simulation is shown in FIG. FIG. 4 shows the time course of the concentration of each component in the batch test. As described above, according to the present embodiment, the concentration of each component of the treated water is predicted by applying the activated sludge model in the biological aerobic treatment process of the wastewater containing the compound component having biodegradability. it can. Furthermore, since the calculation is originally performed for each component of phenol, thiosulfuric acid, and thiocyanic acid, the concentration of each component of the treated water can be predicted whether it is a single component or a combination of two components.

Example 2: Simulation of a batch test for phenol, thiosulfuric acid, and thiocyanic acid (when one kind of bacteria decomposes two components)
Hereinafter, a simulation method when it is set in Example 1 that two components of thiosulfuric acid and thiocyanic acid are decomposed by one kind of bacteria (sulfur component degrading bacteria) will be described. Here, the reason why the thiosulfuric acid and thiocyanate-degrading bacteria are used as the sulfur component-decomposing bacteria is that in the actual treatment, it was estimated that the sulfur component-decomposing bacteria correspond to sulfur oxidizing bacteria.

  The simulation is performed in the same flow as in FIG. 1, and the biodegradable compound component, batch test method, analysis step 2, parameter setting step 6, dissolved oxygen concentration 7 and component concentration conversion step 12 are performed in the same manner as in Example 1. It was. However, the COD conversion step 4 and the component concentration conversion step 12 are changed to a sulfur conversion step, and the component concentration, stoichiometry parameter, and reaction rate parameter in Table 1 are set as shown in Table 4 below, and calculation is performed. In step 10, the thiosulfate-decomposing bacterium concentration and the thiocyanate-decomposing bacterium concentration are summarized into a sulfur component decomposing bacterium concentration and shown in Table 4 below:

Further, as shown in Table 5 below, in terms of the stoichiometric relationship in the processes ρ ₂ and ρ ₃ , bacterial growth due to decomposition of thiosulfuric acid and thiocyanic acid occurs in the sulfur component-decomposing bacteria.

Further, as shown in Table 6 below, the term of the bacterial concentration in the reaction rate equation in the processes ρ ₂ and ρ ₃ was replaced with a sulfur component degrading bacterium.

The result of the simulation is shown in FIG. FIG. 5 shows the time course of the concentration of each component in the batch test. Compared to FIG. 4, the degradation rate increased for thiosulfuric acid. In Example 1, thiosulfate-degrading bacteria (X _S2O3 ) and thiocyanate-degrading bacteria (X _SCN ) were separately calculated to calculate the concentration of each degrading bacterium. In this example, two components of thiosulfate and thiocyanate were calculated. The main reason is that the growth of thiosulfate-degrading bacteria (X _S2O3 ) and thiocyanate-degrading bacteria (X _SCN ) was concentrated in the sulfur component-degrading bacteria concentration (X _S ) because it was set to decompose with one sulfur component-degrading bacterium. It is. For thiocyanic acid, when the sulfur component degrading bacterial concentration (X _S ) was set by calibration in the parameter setting step 6, the result was slightly lower than the initial value of X _{SCN of} Example 1, and the degradation rate was slightly reduced. However, there was no big difference.
Here, it is desirable to select which one of Example 1 and this example is better based on a comparison between experimental values and calculated values, whether or not a reaction close to an actual phenomenon can be calculated, and the like. In this example, it was considered that the accuracy of the calculated value could be improved.

  As described above, according to the present example, with respect to the method for determining the type and concentration of bacteria that degrade biodegradable compound components, basically one type of bacteria is responsible for the degradation of one component. It is desirable to cope with this, but in order to improve the calculation prediction according to the actual phenomenon and the calculation prediction accuracy, it may be set so that one kind of bacteria corresponds to a plurality of components. Moreover, by converting thiosulfuric acid and thiocyanic acid concentrations to sulfur concentrations, it became possible to track the mass balance of sulfur, and to understand the behavior of sulfur components. In addition, the calculation considering the specific endogenous respiration rate was performed, but the results were in a negligible range, and no clear difference was found.

Example 3: Simulation of oxygen consumption rate test targeting cresol Hereinafter, a simulation method of an oxygen consumption rate test targeting o-cresol as a biodegradable organic substance component will be described.
In the oxygen consumption rate test, components were added to a 1 L reaction vessel so that the o-cresol concentration was 15 mg / L, and the MLSS concentration was 330 mg / L. During the test, the dissolved oxygen concentration was measured with a dissolved oxygen concentration meter, and the pH was measured with a pH meter. The dissolved oxygen concentration was controlled to 3.25 mg / L and pH 7.5.

からｏ−クレゾールの理論的酸素消費量を算出した。その結果、ｏ−クレゾール１ｍｇあたりの理論酸素消費量は２．５２ｍｇであった。The analysis step 2 is a step of analyzing the component concentration in the wastewater flowing into the biological treatment process. Here, although it is the initial component concentration in the oxygen consumption rate test apparatus, the o-cresol concentration was confirmed by JIS K0102 absorptiometry. The COD conversion step 4 is a COD conversion step of converting the concentration of o-cresol obtained in the analysis step 2 into a COD concentration. For COD conversion, the following chemical reaction formula (4):

From this, the theoretical oxygen consumption of o-cresol was calculated. As a result, the theoretical oxygen consumption per 1 mg of o-cresol was 2.52 mg.

Conversion was performed according to this correlation 3, and the o-cresol concentration was converted to a COD concentration of 9. In the parameter setting step 6, the parameters used in the calculation step 10 were set.
For parameter 5, the growth yield, the maximum specific growth rate, the saturation constant, and the concentration of cresol-degrading bacteria used in calculation step 10 described later were set. In the setting method, the growth yield was determined by the calculation formula (3) from the COD equivalent concentration of o-cresol and the oxygen consumption obtained from the oxygen consumption rate test. Specifically, since o-cresol was added to 13 mg / L, the COD concentration was 3 to 32.7 mg / L from correlation 3.

｛式中、ＯＵＲ_Tは、時間Ｔにおける酸素消費速度であり、ｔ₁は、ばっ気前の時間であり、ｔ₂は、ばっ気後の時間であり、そしてＴは、ばっ気期間において、酸素消費速度を求めたい時間である。｝を用いて求めた。但し、これに限らず、その他の近似方法を使ってもよい。When obtaining the oxygen consumption at this time, it is necessary to always observe the decrease in dissolved oxygen concentration in the oxygen consumption rate test. However, during the test, since the dissolved oxygen concentration is 3.25 mg / L, since aeration is performed, an accurate oxygen consumption rate at that time cannot be obtained. Therefore, here, the oxygen consumption rate at the time of aeration is obtained by performing linear approximation from the value of the oxygen consumption rate at the time of no aeration before and after aeration. For example, when the oxygen consumption rate at time t ₁ is 10 mg / L / hr, the oxygen consumption rate at time t ₂ is 7.5 mg / L / hr, and aeration is performed from time t ₁ to time t ₂ The oxygen consumption rate at time T during this time is expressed by the following equation (8):

{Where OUR _T is the rate of oxygen consumption at time T, t ₁ is the pre-aeration time, t ₂ is the post-aeration time, and T is the aeration period, This is the time you want to find the oxygen consumption rate. } Was used. However, the present invention is not limited to this, and other approximation methods may be used.

By integrating the oxygen consumption rate thus determined with time, the oxygen consumption was 13.9 mg / L, so the growth yield was (32.7-13.9) /32.7= Calculated as 0.57. In addition, it was considered that the degrading bacteria correspond to the cresol degrading bacteria. The maximum specific growth rate, the saturation constant, and the cresol-degrading bacterial concentration are determined by a calibration method, and the value of χ ² shown in the calculation formula (2) is calculated from the actual value, the calculated value, and the standard deviation of the actual value. The value of the parameter when the value of χ ² was minimized was calculated. The actual values of the oxygen consumption rate and the component concentration were obtained by actual measurement during the oxygen consumption rate test in this example. The calculated value was obtained by the method of calculation step 10 described later.

As the dissolved oxygen concentration 7, a control value of 3.25 mg / L in the batch test was used.
In the calculation step 10, the change over time of the o-cresol concentration was simulated using the COD concentration 9, the dissolved oxygen concentration 7 and the parameter 5, and the COD concentration 11 of the treated water o-cresol was obtained. As the calculation method, the arithmetic expression (1) was used. Table 7 below shows the concentration and parameters of each component used in the calculation:

  Table 8 below shows the stoichiometry used in the calculations:

  And Table 9 below shows the reaction rate equation used for the calculation:

In the component concentration conversion step 12, similarly to the COD conversion step 4, the o-cresol COD concentration 11 of the treated water was reconverted to the o-cresol concentration 13 by the correlation 3 between the o-cresol concentration and the COD concentration.
The result of the simulation is shown in FIG. FIG. 6 shows the time course of o-cresol concentration. As described above, according to the present embodiment, the present invention can be applied to components other than phenol, thiosulfuric acid, and thiocyanic acid, and the component concentration can be obtained even if the theoretical oxygen consumption is used for the correlation 3. be able to.

According to the present invention, it is possible to calculate the component concentration of treated water by setting the type of bacteria that decompose the components of the soluble slow-degradable components that were not included in the activated sludge model. Yes, it is industrially useful.

1 Outline of water quality simulation method 2 Analysis process 3 Correlation between each component and COD concentration 4 COD conversion process 5 Parameter 6 Parameter setting process 7 Dissolved oxygen concentration 8 Dissolved oxygen concentration measurement process 9 COD concentration 10 Calculation process 11 Treated water Each component COD concentration 12 Component concentration conversion process 13 Each component concentration of treated water 21 Oxygen consumption rate test device 22 Microbial sludge 23 Nitrification inhibitor 24 Stirrer 25 Nutrient salt 26 Target component 27 Dissolved oxygen concentration meter 28 Data recording device 29 Air supply Device 30 pH meter 31 Acid / alkali supply device 32 Heater 33 Constant temperature water bath

Claims (2)

A water quality simulation method in a process of biologically aerobically treating wastewater containing a compound component having biodegradability in a biological reaction tank,
An analysis step of analyzing each component concentration of the compound component in the wastewater flowing into the biological reaction tank;
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, COD conversion that converts the analysis value of each component concentration into the COD concentration of each component Process,
A parameter setting step for setting the growth yield as a stoichiometric parameter, the saturation constant as a reaction rate equation parameter, the maximum specific growth rate, and the type and concentration of bacteria that degrade the compound components;
A dissolved oxygen concentration measuring step for measuring a dissolved oxygen concentration in the biological reaction tank;
Using the COD concentration of each component, the growth yield, the saturation constant, the maximum specific growth rate, the seed and concentration of bacteria that decomposes the compound component, and the dissolved oxygen concentration, the following equation (1) :

{Where C _i is the concentration of each component, i is the serial number representing each component, P _ij is the stoichiometric parameter, j is the serial number representing each process, and ρ _j Is a reaction rate equation (a rate equation including a reaction rate equation parameter). } To calculate the COD concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank,
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, the calculated COD concentration of each component of the biologically treated water is calculated as follows: Including a component concentration conversion step for converting to each component concentration,
The parameter setting step includes
(A) A method of determining by calibration using the biodegradable compound component concentration and the dissolved oxygen concentration separately collected in advance in time series in the inflowing wastewater and treated water,
(B) For each of the components, the biological aerobic treatment is performed for each component alone to continuously measure the dissolved oxygen concentration, and the oxygen consumption rate is calculated from the measured value. A step of setting the stoichiometric parameter and the reaction rate equation parameter using any one of the methods of determining from oxygen consumption rate data,
The waste water is a safe water generated in the coke production process,
Among the compound components, the organic component is phenol, and the inorganic component is thiosulfuric acid and thiocyanic acid,
For simulations of thiosulfuric acid and thiocyanic acid,
Instead of the COD conversion step, a sulfur conversion step of converting the thiosulfuric acid and thiocyanic acid concentrations into sulfur,
A sulfur calculation step for calculating the sulfur concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank;
A water quality simulation method that employs a sulfur reconversion step of reconverting the calculated sulfur concentration of each component of biologically treated water into a thiosulfuric acid concentration and a thiocyanic acid concentration. A water quality simulation apparatus for use in a process of biologically aerobically treating wastewater containing a compound component having biodegradability in a biological reaction tank,
Analyzing means for analyzing each component concentration of the compound component in the wastewater flowing into the biological reaction tank;
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, COD conversion that converts the analysis value of each component concentration into the COD concentration of each component Means,
Parameter setting means for setting the growth yield as a stoichiometric parameter, the saturation constant as a reaction rate equation parameter, the maximum specific growth rate, and the type and concentration of bacteria that degrade the compound components;
A dissolved oxygen concentration measuring means for measuring a dissolved oxygen concentration in the biological reaction tank;
Using the COD concentration of each component, the growth yield, the saturation constant, the maximum specific growth rate, the type and concentration of bacteria that degrade the compound component, and the dissolved oxygen concentration, the following equation (1):

{Where C _i is the concentration of each component, i is the serial number representing each component, P _ij is the stoichiometric parameter, j is the serial number representing each process, and ρ _j Is a reaction rate equation (a rate equation including a reaction rate equation parameter). }, The calculation means for calculating the COD concentration of each component in the treated water after the biological aerobic treatment in the biological reaction tank,
Based on the correlation between each component concentration and one COD concentration selected from COD _Cr , COD _Mn, and theoretical oxygen consumption, the calculated COD concentration of each component of the biologically treated water is calculated as follows: Component concentration conversion means for converting each component concentration,
The parameter setting means includes
(A) Means for determining by calibration using each biodegradable compound component concentration and dissolved oxygen concentration separately collected in advance in time series in the inflowing wastewater and treated water,
(B) For each of the components, the biological aerobic treatment is performed for each component alone to continuously measure the dissolved oxygen concentration, and the oxygen consumption rate is calculated from the measured value. Means for setting the stoichiometric parameter and the reaction rate equation parameter using any one of means for determining from oxygen consumption rate data,
The waste water is a safe water generated in the coke production process,
Among the compound components, the organic component is phenol, and the inorganic component is thiosulfuric acid and thiocyanic acid,
For simulations of thiosulfuric acid and thiocyanic acid,
Sulfur conversion means for converting thiosulfuric acid and thiocyanic acid concentrations into sulfur instead of the COD conversion means;
And sulfur calculating means for calculating the sulfur concentration of each component in treated water after the biological aerobic treatment in the biological reaction tank,
A water quality simulation apparatus that employs sulfur re-converting means that re-converts the calculated sulfur concentration of each component of biologically treated water into a thiosulfuric acid concentration and a thiocyanic acid concentration.

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