JP6242436B1 - Pig farm manure mixed wastewater treatment method and circulation type pig farm manure mixed wastewater treatment system - Google Patents

Abstract

[PROBLEMS] To provide pig manure that can be used not only by large-scale pig farmers but also by small-scale pig farmers, and that can easily and efficiently separate solid and liquid components of swine manure mixed wastewater. An object is to provide a mixed wastewater treatment method. A first agglomeration reaction and a coarse floc that form a micro floc by simultaneously adding and stirring a plurality of flocculant aqueous solutions to a swine manure mixed wastewater exhibiting alkalinity near a pH value of 7 in the same agglomeration reaction tank And the second agglomeration reaction forming the same agglomeration reaction tank at the same time, and the first agglomeration reaction and the second agglomeration reaction are completed, so that The liquid component is completely solid-liquid separated to produce sludge and clarified water. [Selection] Figure 1

Description

  The present invention relates to a swine manure mixed wastewater treatment technique, and in particular, a swine manure mixed wastewater treatment method for solid-liquid separation treatment of a solid component and a liquid component in a swine manure mixed wastewater using a flocculant, and the method described above. It is related with the circulation type pig farm manure mixed waste water treatment system which purifies the clear water produced | generated and circulates in a pig farm.

  Conventionally, drainage from barns has been regulated by laws such as the Livestock Excretion Law, Water Pollution Control Law, and Odor Control Law. According to the Water Pollution Control Law, health items (ammonia, ammonium compounds, nitrite compounds, etc.) and living environment items (biochemical oxygen demand (BOD), suspended solids (SS), coliform group count, nitrogen content) Standard values for wastewater are established for phosphorus content, etc.). At present, the livestock industry has a tentative standard value that is more gradual than the general wastewater standard (for example, nitrate nitrogen has a standard value of 100 mg / L, but it is up to July 2016. The provisional reference value is 700 mg / L.), However, will be gradually lowered to approach the general reference value in the future, so it is expected that management will be difficult with the current processing method. For this reason, particularly small and medium-sized pig farms with several hundred to 1,000 heads generate manure mixed wastewater with a high concentration of environmentally hazardous substances, and are struggling with measures against environmental pollution. Most of the manure mixed wastewater (98%) is water, but the BOD concentration is very high organic substance concentration of 6,000 to 10,000 mg / L, and a large aeration treatment facility is used for the treatment. ing.

  There is methane fermentation treatment as a wastewater treatment technology that contains a lot of moisture. Although methane fermentation has the advantage of being able to recover energy by biogasification, the cost of the treatment of wastewater after decomposition is high. It is difficult to apply to large scale pig farmers. In addition, in order to reduce the risk of occurrence of infectious diseases of livestock such as foot-and-mouth disease in recent years, it has become difficult to transport feces and urine over a wide area and process them on a large scale.

  Against this background, pig farms are expected to be short of processing capacity due to an increase in the load on manure processing equipment even if the head is increased to improve productivity. On the other hand, the fact is that there is no money or land to construct a new manure treatment facility. For this reason, development of a processing apparatus and processing system with higher processing efficiency is desired, utilizing the existing manure processing facility.

  Here, as a prior art, in Patent Document 1, “a multi-tank excrement treatment tank in which at least three or more tanks are arranged in series is provided, and each tank constituting the multi-tank excrement treatment tank is provided. A livestock excreta treatment system characterized by having a step which becomes lower in the downstream tank so that the sewage mixed sewage is naturally sulfided and moves to the next tank at the overflow port "(" Claims 1 ”and FIG. 1). Patent Document 2 describes“ a primary tank that mixes manure and anaerobically treats, a secondary tank that precipitates manure treated in the primary tank, A manure processing system comprising a separator for separating manure precipitated in the next tank into a solid and a liquid and a urine transpiration treatment facility for transpiration of the liquid ”(“ Claim 1 ” ”, See FIG. 1).

  The livestock excrement disposal system described in Patent Document 1 is provided with a multi-tank excrement disposal tank as described above, and “the capacity of each tank is a first tank based on the amount of manure generated per day. 6 for 5 days, 2nd tank 7 for 4 days, 3rd tank 8 for 3 days, 4th tank 9 for 2 days, 5th tank 10 for 1 day "(paragraph" 0044 ", As shown in FIG. 1, it is necessary to secure a vast site, and it is expected that the initial capital investment is large, and it takes a very long time to purify manure.

  The manure processing system described in Patent Document 2 is also provided with a large number of treatment tanks and treatment facilities. “The manure mixing primary tank 2 is located in the lower part of the barn 1 and performs manure mixing by anaerobic treatment for several months. The scum is prevented from moving and odor is prevented by providing the stopper 20. The pumping pump 3 removes the supernatant of the excreta treated in the primary excrement mixing tank 2 and performs secondary operation. It is transported to the tank 4. The primary tank 2 moves manure by a natural flow method due to overflow, and the secondary tank 4 stores the supernatant that has been transported in the manure mixed primary tank 2, Further, a sedimentation treatment is performed here, and the pumped water pump 5 conveys the supernatant liquid material after the treatment to the solid-liquid separator 6. The solid-liquid separator 6 uses, for example, a screen from the liquid material. The residue separated from the solid is transported to the compost house 7, and the liquid material is transported to the water amount adjustment tank 8. The water amount adjustment tank 8 functions as a storage tank and a sedimentation tank. From this, the pumping pump 9 transports a liquid material with little impurities, ie, excluding solids, to the urine spraying pipe 16 of the urine transpiration facility 10. The urine spraying pipe 16 is, for example, a porous pipe The liquid material is sprayed from the perforations throughout the entire area of the urine transpiration facility 10 ”(see page 2, column 3, line 36 to column 4, line 4, FIG. 1 of the specification). ), The equipment will be large, and the installation and maintenance costs will be enormous. In addition, “The sediment 18 deposited on the bottom of the manure mixing primary tank 2 and the secondary tank 4 is appropriately removed by vacuum or the like” (the specification, page 2, column 4, lines 9 to 11). There is a labor and cost for this removal.

  The manure processing systems described in Patent Documents 1 and 2 described above use “microorganism materials capable of decomposing organic matter” or “organic materials containing special bacteria” for manure processing, which increases the size of the equipment. This is a factor that takes time to process. Therefore, a solid-liquid separation treatment technique that does not require a large-scale facility as described in Patent Documents 1 and 2 by performing solid-liquid separation processing of a solid component and a liquid component from a suspension using a flocculant in a short time. Can be applied.

  As a solid-liquid separation treatment technique using a flocculant, for example, Patent Document 3 discloses that “a storage tank into which suspended wastewater flows, a precipitation tank connected to the storage tank through a partition wall, and the stirring tank” A slurry dehydrator installed movably below, a fresh water tank connected to the settling tank via a partition wall, agitating and agitating the inside of the stirring tank, and water after dehydration in the stirring tank An air pump to be circulated, a first filter that separates sludge in the sludge water that has flowed into the agitation tank and flows out to the settling tank, and a second filter that further filters the supernatant water of the settling tank and leads it to the fresh water tank It is described as “a polluted water purification system” (see “Claim 1”) in which an inorganic neutral flocculant is added to all of the storage tank, the sedimentation tank, and the fresh water tank. Yes.

  Patent Document 4 states that “in the method of removing impurities in raw water by adding at least two kinds of flocculants, some flocculants (A) of the at least two kinds of flocculants are raw water. The flocculant is controlled according to the concentration index of the suspended solids, and the flocculant (B) different from the flocculant (A) of the at least two types of flocculants is the concentration index of the suspended solids. Is described as "impurity agglomeration method characterized in that agglomeration conditions are controlled according to different water quality indicators" (see "Claim 1").

  Further, Patent Document 5 discloses that “a coagulation treatment device that introduces raw water and performs coagulation treatment, a coagulant addition device that adds coagulant to the coagulation tank, an oil content measurement device that measures the oil concentration in the raw water, and oil content measurement. It is characterized by comprising a control device that calculates the required amount of coagulant corresponding to the oil concentration from the measured value of the device and thereby controls the amount of coagulant added, and a floating separation device that floats and separates the coagulation treatment liquid. "Olinoco oil-containing emulsion wastewater treatment equipment" (see "Claim 1").

JP 07-327535 A Japanese Patent Publication No. 07-061479 JP 2014-087799 A JP 2008-264723 A JP 09-225474 A

  The “polluted water purification system” described in Patent Document 3 adds “inorganic neutral flocculant” to all of the “primary sedimentation tank 11”, “secondary sedimentation tank 12”, and “fresh water tank 13”. Between the “primary settling tank 11” and the “secondary settling tank 12” and between the “secondary settling tank 12” and the “fresh water tank 13”, the “first filter F1” and the “second filter”, respectively. F2 ”is provided, and compared with the“ feces and urine treatment system ”described in Patent Documents 1 and 2, it is assumed that the equipment is downsized. There is a staged filter process and further processing steps need to be simplified. Further, in Patent Document 3, “inorganic neutral flocculant” is not only “separation of sludge from suspended wastewater generated in the field of civil engineering works such as industrial systems and river works”, but “livestock excreta”. It is described that it can also be used for “treatment” (see paragraph “0001”), and “industrial applicability” is “(3) Agriculture, forestry and fisheries field”: livestock, dairy and aquaculture.・ Sewage treatment such as horticulture and water quality improvement. Wastewater treatment for improving contaminated soil and farmland infrastructure. However, there are no specific examples of “livestock excreta treatment” and “sewage treatment / quality improvement of livestock / dairy farming”.

  Further, in the “impurity flocculation method” described in Patent Document 4, the “addition concentration and pH” of the “inorganic flocculating agent” is controlled according to the “concentration index of suspended solids in raw water” and “raw water” Since it is necessary to control the “addition concentration” of the “organic flocculant” in accordance with the “water quality index different from the concentration index of suspended solids”, the configuration of the system becomes complicated. Patent Document 4 neither describes nor suggests application to swine manure mixed wastewater treatment.

  Furthermore, “Olinoco oil-containing emulsion wastewater” to be treated by the “Olinoco oil-containing emulsion wastewater treatment device” described in Patent Document 5 is different from the swine manure mixed wastewater, and is described in Patent Document 5 above. It is presumed that it is not easy to apply the wastewater treatment technology applied to swine manure mixed wastewater treatment. Further, the “Olinoco oil-containing emulsion wastewater treatment device” is prepared by adding “inorganic flocculant” to “raw water” introduced into “reaction tank 1” as shown in FIG. It is a configuration in which an agglomeration reaction is performed, and the “reaction liquid in the reaction tank 1” is further introduced into the “floc production tank 2”, and the “polymer flocculant” added here produces “floc”. The “inorganic flocculant” and the “polymer flocculant” are charged in separate tanks, that is, in separate steps, and simplification of the flocculant charging step is desired. In addition, the “Olinoko oil-containing emulsion wastewater treatment device” of Patent Document 5 must be provided with an “oil content measurement device 9” and “measure the oil content in current water by solvent extraction with emulsion destruction and infrared absorption analysis”. The configuration is complicated.

  Therefore, the present invention can be used not only by large-scale pig farmers but also by small-scale pig farmers, and can easily and efficiently perform solid-liquid separation treatment of solid and liquid components of swine manure mixed wastewater. An object of the present invention is to provide a method for treating swine manure mixed wastewater.

  Another object of the present invention is to provide a circulation type swine manure and wastewater treatment system that circulates the clear water produced in the method for treating swine manure and wastewater to the barn.

In order to achieve the above object, according to the first aspect of the present invention, in the same agglomeration reaction tank, a plurality of aggregating agent aqueous solutions are simultaneously added to and stirred in the swine manure mixed wastewater to form a micro floc. And the second agglomeration reaction forming a coarse floc are carried out substantially simultaneously in the same agglomeration reaction tank, and the first agglutination reaction and the second agglomeration reaction are completed to A swine manure mixed wastewater treatment method for producing sludge and clarified water by solid-liquid separation treatment of a solid component and a liquid component, wherein the pig farm wastewater is collected from swine manure collected from a pig farm. Inorganic system selected from at least one of sulfuric acid band, polyaluminum chloride, and calcium sulfate, which is a raw water of mixed waste water and has not yet been subjected to solid-liquid separation treatment. Flocculant In the first aggregating reaction, the micro flocs are formed by the aggregating action of the inorganic aggregating agent on the solid component, and the second aggregating reaction is performed. The coarse floc is formed by two different aggregating actions of the aggregating action of the organic polymer flocculant on the solid component and the aggregating action of the organic polymer flocculant on the fine floc, Including a step in which three coagulation actions of one coagulation action in the first coagulation reaction and two different coagulation actions in the second coagulation reaction proceed simultaneously, and the plurality of coagulants are added to the swine manure mixed waste water A pH adjuster aqueous solution is added simultaneously with the aqueous solution, and the aqueous solution of the inorganic flocculant and the pH adjuster aqueous solution are acidic. An aqueous solution of an organic polymer flocculant is characterized in that it is a neutral.

The invention of claim 2 is characterized in that, in the invention of claim 1, the pH adjuster contains at least citric acid.

Further, in the invention of claim 3, and characterized in that flow changing the pig manure wastewater treatment method by solid-liquid separation process was clarified water that is generated according to claim 1 or claim 2 as washing water for the barn To do.

The invention of claim 4 is a circulation type swine manure mixed wastewater treatment system, which is raw water of wastewater mixed with pig manure collected from a livestock barn in a pig farm, and solid-liquid separation treatment has not been performed A plurality of flocculant aqueous solutions are simultaneously added to and stirred in the swine manure wastewater, and the first agglomeration reaction for forming micro flocs and the second agglomeration reaction for forming coarse flocs are performed substantially simultaneously, A flocculation reaction tank that completes the flocculation reaction and the second flocculation reaction, and separates the solid component and the liquid component of the swine manure waste water to produce sludge and clarified water; and the clarified water A septic tank for generating purified water by purifying the purified water, a reflux means for returning the purified water to the barn, and a dehydrator for dehydrating the sludge. Low in calcium sulfate Both of them are an aqueous solution produced with an inorganic flocculant selected from any one of the above and an organic polymer flocculant made of polyacrylamide, and the flocculence reaction tank is a micro-fluidizer in the first flocculant reaction. The floc is formed by the aggregation action of the inorganic flocculant on the solid component, and in the second aggregation reaction, the coarse floc is formed by the aggregation action of the organic polymer flocculant on the solid component and the organic flocculant. Formed by two different aggregation actions of the polymer flocculant with respect to the micro flocs, one aggregation action in the first aggregation reaction and two different aggregation actions in the second aggregation reaction It is a reaction tank in which three coagulation actions proceed simultaneously, and the swine manure mixed wastewater is a pH adjusting agent water together with the plurality of coagulant aqueous solutions. Liquid has been added at the same time, the aqueous solution and the pH adjusted aqueous solution of the inorganic coagulant is acidic, aqueous solution of the organic polymer flocculant is characterized in that it is a neutral.

  According to the mixed wastewater treatment method for swine manure of the present invention, the solid-liquid separation treatment of the solid component and the liquid component of the swine manure mixed wastewater can be efficiently performed in one agglomeration reaction step. The waste water treatment system can be simplified and the waste water treatment system can be simplified.

  According to the circulation type pig manure mixed wastewater treatment system of the present invention, since the solid-liquid separation treatment of manure can be performed for each piggery and breeding house, the facility site can be greatly reduced, and It can be used.

  According to the circulation type livestock manure mixed waste water treatment system of the present invention, BOD (biochemical oxygen demand) and SS (suspension or suspended solids) can be greatly reduced by using the flocculant in the primary treatment. And the load on subsequent processes (purification, filtration, etc.) can be greatly reduced.

It is explanatory drawing of the circulation type pig farm manure mixed waste water treatment system in embodiment of this invention.

  Hereinafter, the present invention will be described more specifically with reference to preferred embodiments. However, the following embodiment is merely an example embodying the present invention, and the present invention is not limited to this.

(Embodiment 1)
First, the swine manure mixed wastewater treatment method of Embodiment 1 will be described. Swine manure mixed wastewater is wastewater mixed with swine manure collected from a pig farm and has not been subjected to any special solid-liquid separation treatment, and is sometimes referred to as “raw water”. This swine manure mixed wastewater is characterized in that it is a wastewater having a stable alkalinity having a pH value of around 7 (neutral). The applicant of the present application can perform solid-liquid separation processing of the solid component and the liquid component in a single agglomeration reaction process by using this characteristic of the swine manure mixed wastewater, and can efficiently perform the swine manure mixed wastewater treatment. I found a way.

  Usually, when coagulation processing of to-be-processed water, such as waste water and sewage, is carried out, it is necessary to adjust pH according to the density | concentration parameter | index of to-be-processed water as described in patent document 4, for example. This is because the aggregating effect of the aggregating agent is the greatest when the water to be treated is neutral. That is, the degree of pH adjustment increases as the variation in the pH value of the water to be treated increases. For example, depending on whether the water to be treated is alkaline or acidic, a step of changing the components of the pH adjuster to completely different ones is required. Moreover, when pH adjustment is automatically controlled, the control method and control means become complicated, and there is a problem that the control means becomes large.

  However, as described above, the applicant of the present application pays attention to the fact that the swine manure mixed wastewater is a wastewater showing a stable alkalinity having a pH value of around 7, and in order to make this wastewater neutral with a large coagulation effect. Has found that an aqueous solution of an inorganic flocculant exhibiting acidity of a substantially constant pH value may be added without using a complicated pH adjusting method / pH adjusting means.

  And in this embodiment, in the same agglomeration reaction tank, the aqueous solution of the inorganic flocculant and the aqueous solution of the organic polymer flocculant are simultaneously added to the raw water of the swine manure mixed waste water, and the stirring means By performing the agitation, the solid component and the liquid component of the raw water were solid-liquid separated. In this solid-liquid separation process, three agglutination reactions proceed simultaneously. First, due to the aggregating action of the inorganic aggregating agent, solid components (such as colloidal particles) of raw water are aggregated to form micro flocs (corresponding to “first aggregating reaction” in claim 1). The fine flocs are adsorbed and crosslinked by the aggregating action of the organic polymer flocculant to form coarse flocs. Further, the solid component of the raw water is agglomerated by the aggregating action of the organic polymer flocculant to form a coarse floc. The formation of coarse flocs by two different aggregating actions of the organic polymer flocculant corresponds to the “second aggregating reaction” according to claim 1. When the formation of the coarse floc is completed, that is, the aggregation reaction is completed, the solid-liquid separation process of the solid component and the liquid component in the raw water is completed. In the prior art, even if a flocculant was added to the raw water in the agglomeration reaction tank and the agglomeration reaction was carried out, the formation of coarse floc was insufficient.Therefore, an additional agglomeration reaction tank was provided after the first agglomeration reaction tank. It was necessary to form a sufficiently large floc through an additional agglomeration reaction step such as adding and stirring another component flocculant to the treated water, and in the present invention, it was necessary to perform a solid-liquid separation process. There is no need to provide an additional agglutination reaction step, and the solid-liquid separation process can be performed efficiently in a short time only by the first agglutination reaction step. Here, “simultaneous addition” includes “simultaneous deviation”. In short, the inorganic flocculant aqueous solution and the organic polymer flocculant aqueous solution may be added to the raw water at a timing such that the three aggregating reactions described above proceed simultaneously.

  As the inorganic flocculant, aluminum sulfate (sulfuric acid band), polyaluminum chloride (PAC), calcium sulfate (gypsum), etc. in which the aqueous solution is acidic are used. As the organic polymer flocculant, the aqueous solution is neutral. Polyacrylamide or the like is used. As described above, neutrality of the water to be treated has the greatest aggregating effect. Therefore, in addition to the inorganic flocculant aqueous solution, a pH adjuster, for example, citric acid whose aqueous solution is acidic is used as an inorganic flocculant. You may add simultaneously with aqueous solution and an organic type polymer flocculant. As described above, since the pH value of the raw water shows a stable alkalinity in the vicinity of 7, the concentration of citric acid does not need to be complicatedly controlled and may be set within a predetermined range.

  In this way, the liquid component generated by the solid-liquid separation treatment, that is, the clarified water, is further purified in the septic tank and circulated for use in the washing water of the barn. The solid component (that is, the coarse floc formed by the agglomeration reaction) can be floated or settled according to the system configuration required by the user by adjusting the pH within the water quality reference value. is there.

(Embodiment 2)
Next, a circulation type swine manure mixed waste water treatment system of Embodiment 2 will be described with reference to FIG. The circulation type swine manure mixed wastewater treatment system 1 performs the solid-liquid separation processing of the pig manure mixed wastewater discharged in the pig farm using the method for treating swine manure mixed wastewater of Embodiment 1 described above. The clarified water produced in (1) is purified in a septic tank and circulated as washing water for a pig farm.

  Swine manure mixed waste water (raw water) 3 discharged from the pig farm 2 is collected in the raw water storage tank 4. Here, the solid-liquid separation process such as the coagulation process is not performed, and the raw water of the swine manure mixed wastewater is stored. However, the storage period is much shorter than before. The raw water 3 stored in the raw water storage tank 4 is injected into the agglomeration reaction tank 6 through the raw water introduction path 5 by the pump P1.

  In the agglomeration reaction tank 6, a mixed solution of an inorganic flocculant aqueous solution and an organic polymer flocculant aqueous solution is added from the flocculant supply tank 7 to the injected raw water 3 through the flocculant introduction path 8 by the pump P 2. , And agitating means 9 connected to the motor M1. In the agglomeration reaction tank 6, as described in Embodiment 1, the formation of fine flocs and formation of coarse flocs are simultaneously performed by the aggregation action of the inorganic flocculant and the aggregation action of the organic polymer flocculant. Solid-liquid separation processing of the solid component and the liquid component in the raw water is performed.

  The clarified water 10 produced by the solid-liquid separation treatment is sent to the septic tank 11 by the pump P3 and purified, the disinfectant 12 is added by the regenerative circulation water tank 13, filtered by the filter F1 by the pump P5, BOD, After clearing the SS water quality standard, it is circulated for use in the washing water of the pig farm 2 and the like. After the recirculated purified water is used in the pig farm 2, it is collected together with manure mixed wastewater and stored in the raw water storage tank 4.

  In the conventional wastewater treatment technology for civil engineering work, an additional agglomeration reaction tank is required in the subsequent process of the agglomeration reaction tank 6 in order to form coarse floc, collect sludge, and discharge clear water. However, in the present invention, since the formation of the coarse floc is completed in the agglomeration reaction tank 6, an additional agglomeration reaction tank as in the prior art is unnecessary. As described above, depending on the configuration of the system used by the user, the coarse floc can be formed so as to float without being settled.

  The solid component sludge (coarse floc) 14 formed in the agglomeration reaction tank 6 is sent to the dehydrator 15 via the pump P4, dehydrated, and recovered as useful materials such as compost.

  Thus, the circulating manure mixed drainage system 1 of the second embodiment is configured. In addition, since each component which comprises the circulation manure mixing drainage system 1 can be implement | achieved by a well-known prior art, special description is abbreviate | omitted. Since the circulating manure mixed drainage system 1 of Embodiment 2 has a simple configuration and can be configured with small-scale equipment, it can be installed for each barn.

  Table 1 shows an example of the water quality analysis results of the raw water 3 and the clarified water 10. As shown in Table 1, the pH is 7.5 for raw water 3 and 7.7 for clarified water 10, and it can be seen that the pH value is alkaline in the vicinity of neutral 7 even after drainage treatment. . In addition, the pH value of this raw | natural water 3 and the clarified water 10 is in the range of the wastewater reference value (5.8-8.6) of the water pollution prevention method. BOD is 2900 mg / l for raw water 3 and 1100 mg / l for clarified water 10, and SS is 4300 mg / l for raw water 3 and 580 mg / l for clarified water 10 and the water quality is remarkably purified. I understand. The clarified water 10 is further purified, added with a disinfectant, filtered, and processed so as to clear the drainage standard values (BOD; 160 mg / l, SS; 200 mg / l, etc.) of the Water Pollution Control Law. Then, by performing a complete solid-liquid separation process in a single agglomeration reaction step, the quality of the clarified water 10 can be significantly improved compared to the raw water 3, so that the agglutination reaction step is further performed after the agglomeration reaction step. It was possible to reduce the burden on the subsequent processing steps.

1 Circulation-type swine pig manure mixed wastewater treatment system 2 Pig farm livestock 3 Pork manure mixed wastewater (raw water)
4 Raw water storage tank 5 Raw water introduction path 6 Coagulation reaction tank 7 Coagulant supply tank 8 Coagulant introduction path 9 Agitation means 10 Clarified water 11 Septic tank 12 Disinfectant 13 Recycling water tank 14 Sludge 15 Dehydrators P1, P2, P3, P4 P5 pump M1 motor F1 filter

Claims (4)

In the same agglomeration reaction tank, a plurality of flocculant aqueous solutions are simultaneously added to the swine manure wastewater and stirred, and the first agglutination reaction that forms micro flocs and the second agglutination reaction that forms coarse flocs are the same as described above. In the agglomeration reaction tank, and by completing the first agglutination reaction and the second agglomeration reaction, the solid component and the liquid component of the swine manure mixed wastewater are subjected to solid-liquid separation treatment and sludge. A swine manure mixed wastewater treatment method for producing clear water,
The swine mixed wastewater is raw water of wastewater mixed with swine manure collected from a pig farm, and solid-liquid separation processing has not been performed.
Producing a plurality of flocculant aqueous solutions with an inorganic flocculant selected from at least one of sulfate bands, polyaluminum chloride, and calcium sulfate; and an organic polymer flocculant that is polyacrylamide,
In the first aggregation reaction, the micro flocs are formed by the aggregation action of the inorganic flocculant on the solid component,
In the second agglomeration reaction, the coarse flocs are two agglomerates different from each other in the aggregating action of the organic polymer flocculant on the solid component and the agglomerating action of the organic polymer flocculant on the micro flocs. Formed by action,
A process in which three aggregation actions of one aggregation action in the first aggregation reaction and two different aggregation actions in the second aggregation reaction proceed simultaneously,
A pH adjuster aqueous solution is simultaneously added to the swine manure mixed wastewater together with the plurality of flocculant aqueous solutions,
A method for treating swine manure mixed wastewater, wherein the aqueous solution of the inorganic flocculant and the aqueous solution of the pH adjuster are acidic, and the aqueous solution of the organic polymer flocculant is neutral.   The method of claim 1, wherein the pH adjuster contains at least citric acid.   A circulating swine pig manure mixed wastewater treatment method, wherein clear water produced by solid-liquid separation treatment by the method for treating swine manure mixed wastewater according to claim 1 or 2 is recirculated as washing water for a livestock barn. Raw water of wastewater mixed with pig manure collected from livestock barns in pig farms and mixed with multiple coagulant solutions to swine manure wastewater that has not been subjected to solid-liquid separation treatment. The first flocculation reaction forming the first flocculant and the second flocculation reaction forming the coarse flocs are performed substantially simultaneously to complete the first flocculation reaction and the second flocculation reaction. An agglomeration reaction tank that produces sludge and clarified water by subjecting the component and liquid component to solid-liquid separation treatment;
A septic tank for purifying the clarified water to produce purified water;
Recirculation means for recirculating the purified water to the barn;
A dehydrator for dewatering the sludge,
The plurality of flocculant aqueous solutions are aqueous solutions formed by an inorganic flocculant selected from at least one of sulfate bands, polyaluminum chloride, and calcium sulfate, and an organic polymer flocculant made of polyacrylamide. Yes,
In the agglomeration reaction tank, in the first agglomeration reaction, the fine flocs are formed by an agglomeration action of the inorganic flocculant on the solid component, and in the second agglomeration reaction, the coarse flocs are the organic system. One aggregating action in the first aggregating reaction is formed by two different aggregating actions of the aggregating action of the polymer flocculant on the solid component and the aggregating action of the organic polymer flocculant on the micro flocs. And a reaction tank in which three aggregating actions of two different aggregating actions in the second aggregating reaction proceed simultaneously,
A pH adjuster aqueous solution is added simultaneously to the swine manure mixed wastewater together with the plurality of flocculant aqueous solutions,
A circulation type swine manure and wastewater treatment system characterized in that the aqueous solution of the inorganic flocculant and the aqueous solution of the pH adjuster are acidic, and the aqueous solution of the organic polymer flocculant is neutral.

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