JPH0226558B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to wastewater treatment using microorganisms fixed on carrier particles, and more specifically, the present invention relates to the treatment of wastewater using microorganisms fixed on carrier particles, and more specifically, the microorganisms fixed on ceramic granules improve the COD, etc. of various industrial and household wastewaters. The present invention relates to a wastewater treatment method and an apparatus for efficiently removing wastewater. (Prior Art) Fluidized bed water treatment methods have been widely known in which wastewater is biochemically treated by attaching a microbial film to carrier particles such as activated carbon or sand to form a fluidized bed. For example, in Japanese Patent Publication No. 59-45439, a biochemical method is proposed using a fluidized bed of granular media to which microorganisms are attached.
A biological treatment method for industrial wastewater for removing BOD, etc. is disclosed, and furthermore, in this treatment method, the aforementioned industrial wastewater is first passed in a downward flow for a certain period of time during the microbial aggregation period at the initial stage of motility, and the microorganisms are It has been proposed that the granular media with the attached microorganisms be fluidized by passing water in an upward flow after the microorganisms have returned to normal function through attachment and agglomeration of the media by facilitating their attachment to the surface of the media. (Problems to be solved by the invention) However, in such conventional methods,
Since the granular medium on which the microorganisms adhere is made of materials such as sand, zeolite, coke, and activated carbon, the effective surface area for the microorganisms to colonize is small, and therefore, biochemically, trace amounts of BOD in the wastewater can be absorbed. Even if removal, nitrification, denitrification, etc. can be performed, for example, the purification effect can be applied to industrial wastewater that contains machine oil, surfactants, etc. that inhibit the oxygen transfer necessary for the growth of microorganisms. In particular, it has become impossible to remove COD from the wastewater due to the decomposition of inorganic pollutants. (Means for Solving the Problems) The present invention is a new wastewater treatment method that solves the conventional problems described above and also realizes the removal of COD from oil-containing wastewater using microorganisms, which was previously considered impossible. This was done with the purpose of providing the law and its equipment. That is, to explain the contents based on the drawings (flow sheets) corresponding to the examples, for example, while adjusting the flow rate as appropriate using the feed pipe 2 connected to the waste water treatment tank 1 that accommodates the primary treated waste water. , the medium in the column 5 which is large enough to feed the wastewater and receive a certain amount of the wastewater, that is, a porous ceramic made of clay as a main component, to which a pore-forming material is added and fired. Microorganisms for treating pollutants in the wastewater flowing into the column are added to the granules, such as organic matter-digesting bacteria such as methane bacteria and rod-shaped bacteria, and inorganic matter-accumulating autotrophic bacteria such as nitrifying bacteria and iron-oxidizing bacteria. This method includes a method and an apparatus for fixing the waste water and treating the waste water by flowing it into contact with a filler 6 made of ceramic particles mixed with a carbonized material such as activated carbon. (Function) First, wastewater, such as oil-containing wastewater, in the wastewater treatment tank 1 is fed by the pump P to the outside of the tank 1 through the feed pipe 2, and into the flow meter 4 via the open valve 3. The flow rate is detected, the flow rate is adjusted by the valve 3, and the excess amount is returned to the processing tank 1 by the compressor C through the return pipe 2a. Further, a feed pipe 2 extending to the flow meter 4
A suitable amount of wastewater is introduced into the column 5 communicating with the external feed pipe 2 through the column 5. In addition, inside this column 5, there are ceramic granules colonized with microorganisms consisting of the above-mentioned inorganic accumulation autotrophic bacteria for removing inorganic pollutants in wastewater and organic matter digesting bacteria for removing organic pollutants. The waste water flowing into the column 5 is mixed with carbide, which acts mainly to adsorb and remove pollutants in the waste water, and purifies the waste water flowing into the column 5. This purification effect is achieved by having a hardness that does not easily deform or turn into powder even when it comes into contact with the wastewater, and by adding a pore-forming material to clay as its main component and firing it, which forms pores during firing. Since the material has continuous pores formed inside it when it is burned away, the effective surface area necessary for colonizing the microorganisms is extremely large, for example, 600,000 m ² when the column 5 is filled with 1 m ³ . This is carried out by the synergistic action of the microorganisms fixed on the ceramic granules and the char, and the wastewater is removed by passing through the internal continuous pores of the porous ceramic granules in which the microorganisms are fixed. By increasing contact with microorganisms, purification efficiency has been significantly improved, and unprecedented transfer of oxygen and nutrients has been sustained. Thus, the COD removal action in the wastewater containing the surfactant and the like is performed. By the way, the COD indication number is mostly caused by the decomposition of inorganic substances in wastewater, but the COD indication number also disaggregates and exists among the BOD indication numbers caused by the decomposition of organic substances, etc. In the present invention, the ceramic granules 6 having a large surface area are used as a culture medium for microorganisms, and the disaggregated parts are used to co-propagate microorganisms that purify inorganic and organic pollutants. The microorganisms and the like perform a wide-ranging action to remove COD and the like caused by the decomposition of inorganic or organic substances in wastewater. (Example) Hereinafter, an apparatus according to the present invention will be specifically described based on an example shown in the drawings. In the figure, 1 is a wastewater treatment tank, and a pump P is installed inside the tank or on the outside of the tank 1. The pump P is connected to a feed pipe 2 having a length that protrudes outside the tank 1.
It will be communicated. The feed pipe 2 further communicates with a valve 3 located on the inlet side of a flow meter 4 that adjusts the flow rate of waste water W fed from inside the waste water treatment tank 1. The wastewater W is fed to the. Incidentally, the excess wastewater is returned to the wastewater treatment tank 1 by driving the compressor C through the return pipe 2a. Next, the feed pipe 2 extending from the other side of the flow meter 4 contains porous ceramic particles made of clay as a main component and sintered with a pore-forming material added thereto. It communicates with the upper opening side of a column 5 filled with a packing 6 consisting of microorganisms attached to ceramic granules in an amount that can at least treat pollutants in incoming wastewater and charred matter mixed with the ceramic granules. It will be done. That is, as mentioned above, the ceramic particles in the column 5 have a special porous shape and have continuous pores inside, so the effective area for colonizing microorganisms is vast. Cultivation of microorganisms such as organic matter-digesting bacteria or inorganic matter-accumulating autotrophic bacteria on the surface of the ceramics at the initial stage of operation can be carried out suitably and in a multifaceted manner, and can be cultured with both the inorganic and organic fungi. When they coexist, they can be colonized and colonized. In addition, these microorganisms also settle on the surface of charcoal such as activated carbon that is mixed with the ceramic granules,
The inflowing wastewater is purified by the assimilation action of the microorganisms, but as mentioned above, the char has the adsorption action of SS and residual oil in the wastewater after the primary treatment such as pseudo-sedimentation. From this point of view, the filler 6 in the column 5 is a blend of 50 to 80% by weight of ceramic granules and 20 to 50% by weight of carbide, or a filler in an inert gas. The purpose of the present invention can be achieved by mixing the two while baking and allowing the microorganisms to colonize the mixture. Moreover, 7 in the figure is a recycled water treatment pipe for sending the waste water W to a reuse destination after purification. The above-mentioned apparatus according to the present invention may be constructed by assembling the treatment tank 1, flow meter 4, and column 5 as individual units as shown in the figure, but it is also possible to install a plurality of them in series according to the amount of wastewater, or It is also possible to change the arrangement as appropriate, such as by providing only a plurality of columns 5. Next, an example in which wastewater W to be treated is highly treated using the apparatus according to the present invention described above will be described. That is, after each wastewater W1 to W4 to be treated discharged from an automobile factory is stored in a primary wastewater treatment tank (not shown), an appropriate amount of an organic or inorganic collector is added to remove inorganic substances from the wastewater. Alternatively, organic substances are generally precipitated. Then, the sediment is discharged outside the tank and formed into a dry cake, and the remaining wastewater is stored in a wastewater treatment tank for secondary treatment, for example, the wastewater treatment tank 1 as shown. The wastewaters W1 to W4 thus collected were subjected to an operation for removing COD, SS, and N-hexane from each of the wastewaters.

[Table] To explain specifically, each of the sample wastewater W1 to W4 is fed through the feed pipe 2 by driving the pump P, and the flow meter 4 and the valve 3
The flow rate is adjusted with
Recycled water treatment in which treated wastewater is fed into columns 5 with a height of 1,300 mm at a rate of 0.7/mm, and purified by microorganisms etc. fixed on the filler 6, and the treated wastewater is connected to the columns 5. The water is discharged through a pipe 7 into a river or other supply route. The treatment values shown in Table 2 indicate the results after treating the wastewater W1 to W4 shown in Table 1 above in the treatment process described above. It has been recognized that the removal effect of COD, SS, and N-hexane from wastewater, which was impossible with other methods, has been achieved.

[Table] Next, other examples will be described. Wastewater W5 containing a nonionic surfactant, two types of oil and fat soaps, and P discharged from the metal silica rod cutting process at the IC base factory is subjected to the first treatment as described above, and then flows into column 5 with a diameter of 100φmm and a height of 1300mm. The wastewater W5 at a flow rate of 2.0/mm at meter 4
was fed and treated in the above-mentioned process order, and the treated water was supplied to a reverse osmosis (RO) plant through the reclaimed water treatment pipe 7 for reuse. Table 3 shows the results of this example.

[Table] Note that the microorganisms colonized in the filling material 6 according to the present invention described above, for example, the inorganic matter-accumulating autotrophic bacteria or the organic matter-digesting bacteria, become a source of COD, etc. contained in the repeatedly fed wastewater W, etc. The pollutants are taken into the cells and accumulated, but they gradually become inactive due to the assimilation of the microbial cells, and become sludge itself, which is mixed in the filling material 6. This will be discharged to the outside of the reaction system together with the SS adsorbed on the carbide such as activated carbon mixed with substance 6. At the breakthrough point of such microorganisms, the washed ceramic granules are used as a culture in which the organic matter-digesting bacteria re-culture and propagate the inorganic matter-accumulating autotrophic bacteria. (Effects of the Invention) As described above, the method and apparatus for treating wastewater using microorganisms according to the present invention have a column containing clay as a main component, adding a pore-forming material to the column, and firing the column. Porous ceramic particles with continuous pores and char are mixed to form a medium for microbial propagation, and the medium is colonized with organic matter-digesting bacteria and inorganic-accumulating autotrophic bacteria to treat various types of wastewater. As a result, the microorganisms on the ceramic granules, which have a vast surface area, are supplied with oxygen and nutrients necessary for their reproduction, while also eliminating COD, etc. in the wastewater, which was considered impossible with conventional methods. long-term removal action, and
By allowing wastewater to pass through the continuous pores of the ceramic granules that are colonized by microorganisms, contact between the wastewater and the microorganisms can be increased, and wastewater treatment can be carried out with extremely high efficiency. Therefore, after the treatment, the recycled water has a COD value of
It can be used in reverse osmosis (RO) plants, which cannot be used unless it is 10 ppm or less, and has a wide range of uses and remarkable effects.

[Brief explanation of drawings]

The drawings are an explanatory diagram of an apparatus and its system showing an embodiment of the present invention. 1...Wastewater treatment tank, 2...Feeding pipe, 3...Valve, 4...Flow meter, 5...Column, 6...
Filling material, 7...Recycled water treatment pipe, C...Compressor, P...Pump.

Claims (1)

[Scope of Claims] 1. A porous ceramic granule having continuous pores, which is made of clay as a main component, added with a pore-forming material, and fired, which is filled in a column; A method for treating wastewater using microorganisms, which comprises colonizing microorganisms capable of treating pollutants in wastewater flowing into the column, mixing the ceramic particles and charred material, and then allowing the wastewater to flow into the column. 2. The method for treating wastewater using microorganisms according to claim 1, wherein the carbonized material is activated carbon. 3. A wastewater treatment method using microorganisms according to claim 1, wherein the microorganisms are coexisting organisms of organic matter-digesting bacteria and inorganic matter-accumulating autotrophic bacteria. 4. A column having a size that can accept a certain amount of waste water, and a porous ceramic granule with continuous pores, which is made of clay as a main component and is made by adding a pore-forming material and firing the column, which is filled inside the column. A microorganism-based wastewater treatment device comprising: a microorganism fixed on the ceramic granules and capable of treating pollutants in wastewater flowing into at least the column; and a charred material mixed with the ceramic granules.