JP5728662B2 - Wastewater treatment of hydrophilic polymer colloid materials - Google Patents

Description

The present invention relates to a wastewater treatment comprising a combination of a synthetic organic colloid, an enzyme and an aerobic microorganism treatment.

In recent years, fruits, beans and root vegetables have been processed at factories, and various processed products are lined up on shelves such as supermarkets. For example, boiled beans typified by soybeans and green peas, frozen vegetables boiled leaves such as spinach and broccoli, freeze dried products of dried yam and radishes, cut fruit containers, cut vegetable bags Many processed products are increasing. These fruits, beans, and root vegetables are processed in a sanitary manner and can be put on the table immediately at home. It is also becoming mainstream to wholesale to side dish food dealers and restaurants. With the increase in these markets, the treatment of wastewater from processing plants such as root vegetables has become a major problem.

Unlike other food factories, the factory wastewater from processing such fruits, beans, and root vegetables is cut and boiled, and contains high-molecular organic substances such as fiber. The main component is the outflow of components. In particular, cellulose, hemicellulose, pectic substances, starches, and proteins present in the vicinity of the cell wall are dissolved and dispersed in the waste water and exist as hydrophilic polymer colloids. These substances have a large molecular weight and have a structure in which cell wall components are difficult to decompose into microorganisms, and cannot be handled by simple wastewater treatment with aerobic microorganisms. Draining into the river as it is may cause harm to rice cultivation or environmental pollution, and it is required to keep it at least below the emission standard.

Conventionally, microbial treatment methods, coagulation sedimentation treatment methods, and pressurized flotation treatment methods are commonly used as techniques for treating organic substances contained in factory wastewater and the like. When the amount of organic matter is low with respect to the amount of wastewater, a microbial treatment method using aerobic microorganisms is performed, and when the concentration is high, the coagulation sedimentation method is preferable, and the pressure flotation method is suitable for separation of fats and oils. However, wastewater from vegetable processing factories often contains insoluble fiber, soluble polysaccharides, proteins, etc., forming a hydrophilic polymer colloid and is difficult to remove by ordinary wastewater treatment.

Various techniques have been generally used as techniques for removing components of hydrophilic polymer colloids that are difficult to treat, but problems still need to be improved in each method.

There is a method in which an ion exchange resin is filled in an ion exchange resin tower, drainage is passed through, and a soluble COD component is removed from the drainage (for example, Patent Document 1). However, when used for wastewater treatment such as food processing, since various substances that have viscosity are contained in the wastewater, the resin tower may be clogged and there are many problems.

There is a method for treating starch-containing water (for example, Patent Document 2) in which cationic polymer fine particles that swell in water and do not substantially dissolve in water are added to water. However, because they are polymer fine particles swollen in water, they are greatly affected by water quality such as polymerization conditions and coexisting ions, and are not suitable for wastewater treatment in which various charged substances are mixed. Since the diameter and the surface area are not constant, there is a problem that the aggregation effect is not stable.

A method of removing the soluble COD component by using fine particulate cationic functional group, anionic functional group, or organic fine particles having hydrogen bonding ability with respect to the water-soluble COD component (for example, Patent Document 3). However, when the COD component in the wastewater contains anionic, cationic, and nonionic components, there is a problem that COD components that can be treated are limited.

JP 2001-276825 A JP 7-83869 JP2007-31492A

Hydrophilic polymer colloidal substances, whether natural or processed, have a slower decomposition rate by microorganisms than low molecular weight substances, and cannot be efficiently decomposed by various wastewater treatment methods using aerobic microorganisms. Further, in the method using a biofilm, since the surface is covered with a viscous material and anaerobic, it is difficult to reduce BOD and COD components in the waste water. On the other hand, the activated carbon treatment immediately clogs the filtration layer, and the coagulation sedimentation method makes it difficult to use a soluble COD component remover in wastewater containing substances having charges of cation and anion. was there.

In other words, wastewater mixed with a wide variety of hydrophilic polymer colloid substances causes various troubles in various aerobic microorganism treatment methods, activated carbon treatment methods, ion exchange methods, and coagulation sedimentation methods. It was difficult to reduce the components. Then, it aims at providing the processing method and apparatus of the waste_water | drain in which a hydrophilic polymeric colloid substance or various hydrophilic polymeric colloid substances are mixed.

The aerobic microorganism treatment according to claim 1 comprises treating the hydrophilic polymer colloid material contained in the waste water with a synthetic organic colloid material or a synthetic organic colloid material and an enzyme, or an activated sludge method or a biofilm fixed bed method, By biofilm fluidized bed method.

The aerobic microorganism treatment according to claim 2 is characterized in that the synthetic organic colloidal substance has an ionic functional group.

The aerobic microorganism treatment according to claim 3 is characterized in that the synthetic organic colloid material is composed of a melamine / aldehyde acid colloid material.

The aerobic microorganism treatment according to claim 4 is characterized in that the enzyme comprises a hydrolase.

The aerobic microorganism treatment method of claim 5 comprises a device for adding a synthetic organic colloid material or a device for adding a synthetic organic colloid material and an enzyme, respectively.

Various hydrophilic polymer colloidal substances, such as natural or processed products, such as pectin, tend to degrade very slowly in microorganisms compared to low molecular weight substances. Cellulose and lignin can only be decomposed by special microorganisms. It was difficult to decompose the wastewater by the aerobic microbial treatment method. On the other hand, the polymer colloidal substance is a hydrophilic colloidal substance having functional groups such as cation and anion in the activated carbon treatment and ion exchange resin tower, and the filtration layer and resin layer are immediately clogged. When these are mixed, there is a problem that it is difficult to use a soluble COD component remover or a flocculant.

As a result of the inventor's repeated research, when a hydrophilic polymer colloid substance exists in the wastewater, it is insolubilized with a synthetic organic colloid substance having a charge opposite to the hydrophilic polymer colloid substance having a charge, and a subsequent process. When various kinds of hydrophilic polymer colloid materials exist, other hydrophilic polymer colloid materials are decomposed by enzymes and treated with aerobic microorganisms at the same time. Methods and equipment for treating materials to reduce organics (COD and BOD components) are provided.

The equipment of the present invention is based on such knowledge, and in combination with wastewater treatment by conventional aerobic microorganisms, various hydrophilic properties can be obtained by adding synthetic organic colloid material or synthetic organic colloid material and enzyme solution to wastewater. It was possible to remove the polymer colloidal material.

Details of the present invention are reported below.

Hereinafter, a first embodiment of the aerobic microorganism treatment of the hydrophilic polymer colloid substance of the present invention will be described. In the first embodiment, the hydrophilic polymer colloid material, which is an organic component contained in the wastewater, is difficult to decompose in a short time by microorganisms, and the hydrophilic polymer colloid material contained in the wastewater is converted into a synthetic organic colloid material or Treated with synthetic organic colloidal substance and enzyme, and at the same time, wastewater treatment with aerobic microorganisms of activated sludge method, biofilm fixed bed method or biofilm fluidized bed method.

In the present invention, for example, a synthetic organic colloid having a charge opposite to one charge of a hydrophilic polymer colloid substance is added to be insolubilized (gelled), and other charged or uncharged hydrophilic When the colloidal polymer is present, it is decomposed by adding enzymes and oxidized by aerobic microorganisms in the aeration tank, and the insolubilized material is separated and discharged together with the sludge in the sedimentation tank.

When a substance larger than atoms or small molecules is dispersed in the presence of the substance, the substance is said to be in a colloidal state. The hydrophilic polymer colloid substance of the present invention is a polymer having a plurality of unit molecules and the like, and refers to a hydrated colloid of saccharides, proteins, etc., such as spheres and threads. The synthetic organic colloidal substance of the present invention refers to an organic substance which is not a natural product but is chemically synthesized and dispersed or solubilized in water to form a colloid.

The colloidal polymer contained in the wastewater is a component constituting plant cell membranes, mainly cellulose, pectin, and hemicellulose. In addition, there are those containing starch, protein, lignin, and chitin. In addition, in the processing of hides and leathers made from leather, bones, etc. There are various things such as chitosan. These high molecular weight colloidal substances are charged as molecules and are neutral, and these substances are often difficult to decompose or assimilate in a short time by activated sludge bacteria.

For example, plants contain protopectin, which is a combination of pectin with cellulose, sugar, phosphate, etc., and exists as a colloid dispersed in water and charged with anions. Pectin is a polysaccharide contained in higher plants. Cellulose and lignin do not undergo degradation once they are formed, whereas pectin is synthesized and degraded by enzymes that coexist in the plant. When fruits and plants are young, they are water-insoluble as protopectin and become soluble pectin by enzymes, making it difficult to deal with wastewater treatment.

Pectic substances are water-insoluble protopectin, soluble pectin, and high sugar pectin consisting of galacturonic acid, methyl lacturonic acid, lacturonic acid amide, acetyl lacturonic acid, and low methoxy pectin. It is a hydrophilic polymer colloidal substance that is electrically charged.

Anionic charged hydrophilic polymer colloids include carbosyl polysaccharides such as protopectin, pectin, sodium alginate, sodium polyacrylate, xanthan gum, gum arabic, etc., sulfate agar, carrageenan, etc. There is starch. Typical examples of the cationic polymer colloidal substance include those having an amino group, and chitosan is a cationic polymer polysaccharide having an amino group, and is contained in crab / shrimp shells and the like. Gelatin or the like as a protein is an amphoteric hydrophilic polymer colloid substance having a carboxyl group and an amino group. Further, modified starches are manufactured and used from neutral to cationic. Neutral ones are guar gum, locust bean gum, cellulose and the like.

The enzyme used in the present invention may be a pure powder or liquid enzyme, a crude enzyme, an immobilized enzyme, or an enzyme-secreted microorganism, and a hydrolase is preferred, although the reaction type and type are not limited.

In biofilm fixed bed facilities, rotating disk facilities, and biofilm fluidized bed facilities that are treated with aerobic microorganisms, aerobic microorganisms when hydrophilic polymer colloidal substances, such as pectin, contained in wastewater adhere to the biofilm. It is preferable to add the synthetic organic colloid substance or the synthetic organic colloid substance and the enzyme of the present invention in order to avoid the trouble that the effect of the aerobic microorganism treatment deteriorates.

The aerobic microbial treatment of the present invention is a method comprising a group of organisms centered on bacteria, increasing dissolved oxygen in water, and microorganisms oxidatively decomposing organic substances taken as oxygen and feed. Organic substances are oxidatively decomposed into carbon dioxide, water, nitrates, sulfates and the like and are taken up as components of microbial cells. The grown microorganisms and insoluble substances create sludge, and the treated water with reduced BOD components is discharged to collect the sludge. In the present invention, the aerobic microorganism treatment includes an activated sludge method (high-speed method, standard method, long-time method, pure oxygen method, etc.) and a biofilm method, and the biofilm method uses a biofilm fixed bed method (rotating disk method). And biofilm fluidized bed method.

The activated sludge method of the present invention is an aerobic microbial treatment method of wastewater consisting of raw water adjustment tank, aeration tank, sedimentation tank, sludge dewatering process, and consists of a group of organisms mainly bacteria, It is a method of increasing the dissolved oxygen and oxidatively decomposing organic matter taken up as feed with this oxygen. The grown microorganisms and insoluble substances create sludge, and the sludge is precipitated in a settling tank, and the treated water having a reduced BOD component in the supernatant water is discharged to collect the sludge. The sludge is returned to be extracted as excess sludge and retains the amount of active microorganisms in the aeration tank. The synthetic organic colloid substance or the synthetic organic colloid substance and the enzyme may be added to any of a raw water adjustment tank, an aeration tank, and a precipitation tank.

The biofilm fixed bed method of the present invention is an aerobic microbial treatment method of wastewater consisting of a raw water adjustment tank, a biofilm fixed bed tank, a sedimentation tank, and a sludge dewatering process, and an appropriate biofilm is installed in the aeration tank. The same applies to the method of decomposing organic matter in the waste water by attaching microorganisms and producing a biofilm in the air (such as a rotating disk). In principle, microorganisms adhere to the biofilm, so there is no need to return the sludge as in the activated sludge method, but it may be returned. Any material can be used as long as the surface area is increased, such as cloth, plastic, mineral, coral, and shell. The same applies to the rotating disk method, but the addition of the synthetic organic colloid substance or the synthetic organic colloid substance and the enzyme may be any of a raw water adjustment tank, a biofilm fixed bed tank, a rotating disk tank, and a precipitation tank.

The biofilm fluidized bed method of the present invention consists of a raw water adjustment tank, a biofilm fluidized bed tank, a sedimentation tank, and a sludge dewatering process. A moderately light filler (carrier) is introduced into an aeration tank to attach microorganisms. This is a method of decomposing organic matter in waste water by flowing with aeration and stirring force. In principle, since microorganisms adhere to the carrier, there is no need to return the sludge as in the activated sludge method, but it may be returned. The material may be anything as long as the surface area increases such as cloth, polyurethane, plastic, synthetic resin (which may be hard or soft) and flows. The synthetic organic colloid substance or the synthetic organic colloid substance and the enzyme may be added to any of a raw water adjustment tank, a biofilm fluidized bed tank, and a precipitation tank.

A second embodiment of the aerobic microorganism treatment of the hydrophilic polymer colloid substance of the present invention will be described. In the second embodiment, the synthetic organic colloidal material has an ionic functional group, and by adding this, the hydrophilic polymer colloidal material contained in the wastewater is insolubilized, and at the same time, the wastewater treatment or enzyme by aerobic microorganisms is performed. In addition, aerobic microorganism treatment is performed. At this time, it is preferable to add a synthetic organic colloid having an ionic functional group which counters the charge of the hydrophilic polymer colloid substance to insolubilize it.

The ionic functional group of the synthetic organic colloidal material of the present invention includes an amino group, N-alkylamino group, N, N-diallylamino group, N, N, N-trialkylammonium halide, and N as a cationic functional group. Typical examples of functional groups that are cationic in the acidic pH range include functional groups such as hydrochlorides of tertiary amino groups and trimethylammonium chlorides of quaternary ammonium groups. In addition, examples of the anionic functional group include a carboxyl group, a sulfone group, and a sulfate group. Examples of the functional group having a hydrogen bonding group include the amino group and the carboxyl group described above, and also include nonionic groups such as a hydroxyl group, an ether group, and an amide group. An ion exchange resin can be used as the synthetic organic colloid material.

A third embodiment of the aerobic microorganism treatment of the hydrophilic polymer colloid substance of the present invention will be described. In the third embodiment, the synthetic organic colloidal material is a melamine / aldehyde acid colloid, which is added to the aerobic microbial treatment step to insolubilize the hardly degradable hydrophilic polymer colloidal material contained in the wastewater, and at the same time Wastewater treatment with aerobic microorganisms or aerobic microorganism treatment is performed by adding enzymes. At this time, the addition of the cationic melamine / aldehyde acid colloidal substance affects the charge of the hydrophilic polymer colloidal substance charged to the anion so that it is insolubilized and can be easily removed.

Hydrophilic polymer colloidal substances are anionic carbosyl polysaccharides such as protopectin, pectin, sodium alginate, sodium polyacrylate, xanthan gum, gum arabic, etc., sulfate agar, carrageenan, etc., phosphate polysaccharide starch, etc. Affects the charge of melamine / aldehyde acid and insolubilizes. In addition, it is assumed that neutral cellulose and the like are insolubilized with melamine / aldehyde acid through hydrogen bonding.

The synthetic organic colloidal substance having a cationic functional group may be an ion exchange resin, but melamine / aldehyde acid is preferred in consideration of the colloidal property with respect to water. As a method for producing a melamine / aldehyde acid colloid, for example, a method described in JP-A-62-266159 is used. Specifically, for example, 63 g (0.5 mol) of melamine and 30 g of paraformaldehyde (1.0 mol as formaldehyde) are added to 93 ml of distilled water, the pH is adjusted to 10.0 with NaOH, and heated to 70 ° C. Melt melamine. Furthermore, after reacting at 70 ° C. for 5 minutes, when it is allowed to stand at room temperature and slowly cooled, crystals of methylolated melamine precipitate. The precipitate is collected on a Buchner funnel, washed with methanol, and dried under reduced pressure. 10 g (0.05 mol) of this methylolated melamine is added to 100 ml of a 1.35% hydrochloric acid solution (with respect to 0.75 mol of melamine) and stirred to obtain an acid colloid solution.

When 10% methylol melamic acid colloid is used, the amount added to the waste water varies depending on pH and the like, but it may be 1 mg / L to 100,000 mg / L with respect to 1,000 mg / L of the hydrophilic polymer colloid, 10 mg / L to 10,000 mg / L is preferred.

A fourth embodiment of the aerobic microorganism treatment of the hydrophilic polymer colloid material of the present invention will be described. In the fourth embodiment, various kinds of hydrophilic polymer colloid materials having different charges in the wastewater can be treated by adding an enzyme to the synthetic organic colloid material, but considering the utilization of aerobic microorganisms. Sometimes hydrolases are preferred.

Many of the hydrophilic polymer colloid materials contained in wastewater are difficult to decompose in a short time by microorganisms. The hydrophilic polymer colloid materials contained in wastewater are treated with synthetic organic colloid materials and other When a hydrophilic polymer colloid substance is made into a single molecule with a hydrolase, assimilation by an aerobic microorganism by an activated sludge method, a biofilm fixed bed method or a biofilm fluidized bed method is improved, and wastewater treatment becomes easy.

The hydrolase of the present invention is an enzyme related to the degradation of plant cell membrane material, such as hemicellulase that degrades hemicellulose mixed with cellulose and other fibrin, cellulase of hydrolase that breaks the glucoside bond of cellulose, fruit These include pectinase, an enzyme that acts on the cell membrane of soft tissue of roots and root vegetables, and pectin that fills the gap between cell membranes, amylase that acts on starch, and the like. It may be a peptidase that decomposes proteins and macromolecular peptides into several peptides. Since the effluents of silk refining factories, leather factories, glues and gelatin manufacturing factories contain high molecular amphoteric colloidal substances of proteins, proteases may be used for the degradation of enzymes.

A fifth embodiment of the aerobic microorganism treatment of the hydrophilic polymer colloid substance of the present invention will be described. In the fifth embodiment, an aerobic microorganism treatment facility having a device for adding a synthetic polymer colloid material or a synthetic polymer colloid material and an enzyme, respectively. The particles of the synthetic organic colloidal substance are desirably free of precipitation when dispersed in water, and may be dispersed in water at a high concentration and added by an adding device. The enzyme may be liquid or solid, and may be added by an adding device.

In a biofilm fixed bed facility, a rotating disk method facility, or a biofilm fluidized bed facility that is an aerobic microorganism treatment, the hydrophilic polymer colloidal substance contained in the wastewater is often viscous, and in particular, pectin is a contact material, It easily adheres to a disc or a carrier, and if this adheres, aerobic microorganisms cannot grow, and the effect of the aerobic microorganism treatment deteriorates. In order to avoid this trouble, the addition of the synthetic organic colloid substance or the synthetic organic colloid substance and the enzyme of the present invention is preferably performed in the aeration tank (biological treatment tank) in which the biofilm is installed or in the installation tank of the biofilm apparatus or before that process. It is. In addition, since the activated sludge method also clogs the pipes and the like, the addition of an aeration tank or earlier is suitable.

The amount of the synthetic organic colloidal substance and the enzyme to be continuously added may be added in accordance with the drainage load, but it is preferable to attach an automatic addition device.

Hereinafter, examples and comparative examples will be described.

(1) 0.03% pectin solution (derived from citrus; Wako Pure Chemical Industries, Ltd.), (2) agar of reactive hydrophilic polymer colloid with hydrophilic polymer colloid and melamine / aldehyde acid (MA) colloid 0.03% liquid (agar powder; Wako Pure Chemical Industries, Ltd.), (3) Starch 0.03% liquid (soluble starch; Wako Pure Chemical Industries, Ltd.), (4) Gelatin 0.03% liquid (powder; Japanese) (5) 10% aqueous solution of a commercial onion unloading solution, (6) 10% aqueous solution of a commercial radish unloading solution, 0.1 ml to 0.1 ml of a melamine / aldehyde acid colloid 10% solution in 100 ml each. 4 ml was added, and it was determined whether or not three insoluble substances were to be formed (pH 7.0 to 6.5).

The results of the reaction are shown in Table 1. Since the pectin solution, agar solution, onion juice, and radish juice produced a cloudy gel material that was inactivated, the anionic charged hydrophilic polymer colloid material It was judged that melamine / aldehyde acid neutralized the charge and precipitated the soluble substance as an insoluble gelled product, which can be effectively used for wastewater treatment.

Wastewater treatment using a fluidized-bed biofilm from a cut vegetable factory This factory is a processing plant that cuts radish, onion, and potato root vegetables as they are. The wastewater is about 130 tons per day. And the wastewater BOD was 200 to 300 mg / L. The equipment outline is raw water adjustment tank (70 m ³ ), flow rate adjustment tank (40 m ³ ), first fluidized bed aeration tank (20 m ³ ), second fluidized bed aeration tank (20 m ³ ), flocculation tank 1 (1 m ³ ), In the equipment and process of the coagulation tank 2 (1 m ³ ), the sedimentation tank (9 m ³ ), and the sludge dehydrator, the amount of treated water was about 6.5 m ³ / hour.

First, the second fluidized bed aeration tank to the polyurethane carriers each 2 cm ³ 4m ³ added was aerated fluidized aeration amount each 1.3 m ³ / min. Coagulation tank 1 is added with polyaluminum chloride A-25 (Taki Chemical Co., Ltd.) 56 ml / min, and coagulation tank 2 is added Ebagrose-151 (Ebara Engineering Service Co., Ltd.) 150 ml / min and sent to the precipitation tank to precipitate sludge. The supernatant liquid was discharged. A 10% melamine / aldehyde acid colloid solution (MA) was automatically added to the first and second fluidized aeration tanks of this facility for one month so that the total amount was 150 mg / L with respect to the waste water. As a comparative example, a treatment in which no melamine / aldehyde acid colloid was added at all was performed for one month and compared. (May-June)

First, raw water BOD for one month without adding melamine / aldehyde acid colloid is 145 to 310 mg / L (average 228 mg / L), and raw water BOD for one month under the condition of adding melamine / aldehyde acid colloid is 155 to 330 mg / L (average 232 mg / L). In this case, the average value is taken from 2 hours before the start of work to 2 hours after the factory line is washed, and every 3 hours, 200 ml is collected from the stock solution adjustment tank, the collected solution is refrigerated and mixed, and the same amount is mixed as one sample. And measured as the average BOD of the day. The monthly average was calculated by adding the daily values for the month and dividing by the number of days.

The comparison data of the treatment with and without the addition of the melamine / aldehyde acid colloidal solution are shown in Table 2. When added, the average BOD of the treated water was 12 mg / L, and there was no adhesion of the adhesive substance to the carrier. On the other hand, when the melamine / aldehyde acid colloid liquid is not added, the BOD is 112 mg / L, and a large amount of the adhesive substance is adhered to the carrier, and after applying pressure so as to crush the polyurethane carrier, the pressure can be removed. It was feared that the fluid carrier was anaerobic without returning to its original state and not showing any effect.

Drainage treatment model experiment by biofilm fixed bed method 40cm deep, 10L capacity water tank with fixed bed as a fixed bed with 3 to 5cm diameter scrubbing and up to 35cm deep, food containing starch 4 parts of factory effluent (COD 540 mg / L), 0.5 parts of radish lowering juice (COD 5000 mg / L) and tap water were added to make 10 parts. (1) 10 ml of melamine / aldehyde acid colloid solution added, (2) 10 ml of melamine / aldehyde acid colloid solution and starch degrading enzyme 90DUN (α-amylase; Wako Pure Chemical Industries, Ltd.), (3) as a comparative example The biofilm fixed bed method without additives was used.

The wastewater having the above composition flowed in at 1 L / day and was discharged from the settling tank provided at 1 L / day. (1) 1 ml of melamine / aldehyde acid colloid solution is added to the solution added 1L per day, (2) is 1 ml of melamine / aldehyde acid colloid solution and 9DUN of amylolytic enzyme, (3) is comparison As an example, no addition was performed. The treatment conditions were pH 6.0, aeration volume of 165 ml / min, water temperature of 35 ° C., and COD was measured by a conventional permanganate method.

Model wastewater treatment by activated sludge method Using the same container as in Example 3, 4 parts of food factory wastewater (COD580 mg / L) containing gelatin in Example 3 and 1 part of onion juice (COD2100) and tap water To make 10 parts. (4) 20 ml of melamine / aldehyde acid colloid solution and (5) 20 ml of melamine / aldehyde acid colloid solution and 200 PUN (for protease biochemistry; Wako Pure Chemical Industries, Ltd.) were added to the aerated and aerated water tank. (6) As a comparative example, an additive sludge method without additives was used.

The wastewater having the above composition was introduced at 1 L / day and discharged from a settling tank provided at 1 L / day. (4) also added 2 ml of melamine / aldehyde acid colloid solution, (5) added 2 ml of melamine / aldehyde acid colloid solution and 20 PUN of enzyme, and (6) was not added as a comparative example. The treatment conditions were pH 7.5, an aeration amount of 165 ml / min, a water temperature of 35 ° C., and COD was measured by a conventional permanganate method.

The results of the aerobic microorganism treatment method of the biofilm fixed bed method of Example 3 are shown in Table 3 (1) to (3), but many of the microorganisms are difficult to decompose, and the permanganic acid of the usual method is included. The COD was measured by the method. In the biofilm fixed bed method, radish protopectin and starch charged with anions are mixed, so the treatment with the enzyme added to the melamine / aldehyde acid colloid solution has the lowest COD, followed by the melamine / aldehyde acid colloid. The liquid was added and the conditions were good, and the fixed bed of the comparative example had the highest COD due to adhesion of the adhesive substance to the fixed bed.

The results of the aerobic microorganism treatment method of the activated sludge method of Example 4 are shown in Table 3 (4) to (6). Many of the microorganisms are difficult to decompose, and the analysis value is COD. Described. In the activated sludge method, the onion protopectin and gelatin charged in the anion are mixed, so the treatment with the enzyme added to the melamine / aldehyde acid colloid solution has the lowest COD, followed by the melamine / aldehyde acid colloid solution. The addition conditions were good, and the activated sludge method of the comparative example had the highest COD.

Claims (2)

Naturally derived anionic hydrophilic polymer colloid containing at least one selected from the group consisting of protopectin, pectin, sodium alginate, xanthan gum, gum arabic, agar and carrageenan contained in wastewater , cationic melamine / aldehyde acid colloid in was not solubilized, waste water treatment method according to the biofilm fluidized bed process or biofilm fixed-bed method, and removing. The wastewater treatment method according to claim 1, wherein the naturally-derived anionic hydrophilic polymer colloid contains at least one of protopectin and pectin.