Zero-carbon source hjdl sewage treatment method

Abstract

The application discloses a zero-carbon source HJDL sewage treatment method, which adopts an HJDL reaction tank; the HJDL reaction tank comprises a microbial hatching system; the HJDL reaction tank is provided with a biological synergistic carrier and a compound microbial agent; the biological synergistic carrier is a carboxymethyl cellulose-diatomite carrier; and metal ions are coordinated on the surface of the biological synergistic carrier. The metal ions can capture phosphate produced by phosphorus accumulating bacteria and perform a chemical reaction, so that the phosphorus removal process does not need a sludge carrier, thereby reducing the demand amount of an organic carbon source in the phosphorus removal process, increasing the utilization rate of the carbon source in sewage, and thus not needing to add an additional carbon source in the environment of low-carbon-source sewage.

Description

TECHNICAL FIELD

[0001] The application relates to the field of sewage treatment, and in particular to a zero-carbon-source HJDL sewage treatment method. BACKGROUND

[0002] With the continuous improvement of urban living standards, the concentration of organic matter in urban sewage in China is becoming lower and lower, and the phenomenon of low carbon source is becoming more and more serious. In the case of lack of carbon source, in order to achieve the standard discharge of phosphorus and nitrogen indicators, most low-carbon-source urban sewage treatment plants need to add a large amount of external carbon source in the process of treating sewage to ensure the normal operation of biological denitrification and biological phosphorus removal.

[0003] However, the cost of adding external carbon source is high, which not only increases the production cost but also causes a large amount of carbon emission. Therefore, it is an urgent problem to be solved in low-carbon-source sewage treatment to improve the effect of phosphorus and nitrogen removal without adding external carbon source and to achieve standard discharge. SUMMARY

[0004] In order to solve the problem that a large amount of external carbon source needs to be added to realize the standard discharge of phosphorus and nitrogen removal of low-carbon-source sewage, and the problem of increasing a large amount of cost and causing carbon emission, the application provides a zero-carbon-source HJDL sewage treatment method.

[0005] In a first aspect, a zero-carbon-source HJDL sewage treatment method is provided, which adopts an HJDL reaction tank; the HJDL reaction tank comprises a microbial incubation system; the HJDL reaction tank is provided with a biological synergistic carrier and a compound bacterial agent; the biological synergistic carrier is a carboxymethyl cellulose-diatomite carrier; the surface of the biological synergistic carrier is coordinated with metal ions; the metal ions include one or a combination of several of aluminum ions, divalent iron ions, calcium ions, zinc ions and copper ions.

[0006] The organic matter carbon source in sewage is decomposed into the energy donor of microorganisms in the process of biological conversion, and can be used as the material basis for the growth and reproduction of microorganisms, the material carrier for biological phosphorus removal and the electron donor in the process of biological denitrification. However, for low-carbon-source sewage, the biological denitrification process is difficult to proceed smoothly, the proliferation of sludge is slow, the discharge amount of excess sludge is insufficient, and the phosphorus removal effect is poor due to the lack of phosphorus carrier.

[0007] The organic carbon source required for unit phosphorus removal far exceeds the organic carbon source required for unit nitrogen removal, so changing the way of biological phosphorus removal can achieve the standard discharge of nitrogen and phosphorus removal without adding a large amount of carbon source. By adopting the technical scheme, the surface of the biological synergistic carrier in the application is coordinated with metal ions, the phosphate is released after the microorganism absorbs the phosphorus, and then captured by the metal ions on the surface of the carrier and chemically reacted, so that the phosphate does not need to be deposited in the sludge carrier, thereby reducing the amount of organic carbon source required in the process of phosphorus removal, increasing the utilization rate of carbon source in sewage, and thus not needing to add additional carbon source.

[0008] The biological synergistic carrier is a carboxymethyl cellulose-diatomite carrier. The diatomite has a porous structure and a large specific surface area, and is chemically stable. Microorganisms can be well adsorbed and survived in the diatomite interstices, providing a good living environment for a large number of anaerobic bacteria such as phosphorus accumulating bacteria. The carboxymethyl cellulose has excellent biocompatibility and environmental friendliness, and has a large number of active groups on the surface, which can provide donors for coordination reactions of metal cations. The carboxymethyl cellulose is covered on the surface of the diatomite. On the one hand, due to its biocompatibility, it can attract a large number of microorganisms to adhere to the biological synergistic carrier. On the other hand, in the process of sewage treatment, microorganisms adhering to the diatomite will gradually absorb organic carbon sources in the sewage to meet the energy required for their growth, but the diatomite will swell anaerobically after adsorbing the organic carbon source, gradually forming a diatomite suspension layer, resulting in the loss of the original normal treatment effect of the diatomite, and the HJDL reaction tank cannot be used normally. The carboxymethyl cellulose covering the surface of the diatomite can enhance the stability of the diatomite and inhibit the occurrence of anaerobic swelling. The two can cooperate to increase the load of microorganisms. The compound microbial agent can form an internal anaerobic, middle facultative and external aerobic structure in a short time by being loaded on the biological synergistic carrier, can simultaneously perform biological nitrification and denitrification, and increase the utilization rate of organic carbon source in the sewage.

[0009] Preferably, the compound microbial agent comprises one or a combination of several of the following: compound denitrifying bacteria, compound phosphorus removal bacteria, compound COD bacteria and anaerobic bacteria.

[0010] Preferably, the compound denitrifying bacteria comprises one or a combination of several of the following: Bacillus subtilis, nitrifying bacteria, denitrifying bacteria, photosynthetic bacteria and lactic acid bacteria.

[0011] Preferably, the compound phosphorus removal bacteria comprises one or a combination of several of the following: Acinetobacter, Aeromonas, Corynebacterium and Microthrix.

[0012] Preferably, the compound COD bacteria comprises one or a combination of several of the following: Gannu compound bacteria and COD degrading bacteria.

[0013] Preferably, the anaerobic bacteria is methanogenic bacteria.

[0014] By adopting the above technical scheme, the mutual cooperation of the composite microbial agent significantly improves the denitrification and phosphorus removal capacity, and the resistance is also significantly improved due to the adoption of multiple strains, so that the composite microbial agent can adapt to various types of sewage; the anaerobic microbial agent contained therein can provide trace elements for the growth and reproduction of microorganisms, accelerate the metabolism of microorganisms, and improve the denitrification and phosphorus removal capacity of microorganisms.

[0015] Preferably, the raw materials used in the biological synergistic carrier include carboxymethyl cellulose, metal salt and diatomite in a mass ratio of (20-40):(3-8):100.

[0016] Preferably, the preparation method of the biological synergistic carrier includes the following steps:

[0017] Diatomite modification: add diatomite into hydrochloric acid solution, soak at a constant temperature of 60-80℃ for 4-6h, then filter, wash to neutral, dry, and grind through a 200-mesh sieve to obtain modified diatomite;

[0018] Preparation of carboxymethyl cellulose-diatomite carrier: disperse the modified diatomite in deionized water; dissolve carboxymethyl cellulose and sodium hydroxide in deionized water and add to the modified diatomite solution, stir and disperse, then add emulsifier and crosslinking agent, stir and react at 60-80℃ for 1-2h; reduce the temperature to 35-45℃, add metal salt, continue to stir and react for 6-8h, then filter, wash, dry, grind, and sieve to obtain the carboxymethyl cellulose-diatomite carrier.

[0019] The metal salt includes one or a combination of several of aluminum chloride, aluminum sulfate, ferrous chloride, iron sulfate, calcium chloride, copper chloride, copper sulfate, copper nitrate, and zinc chloride.

[0020] Preferably, in the diatomite modification, the mass-to-volume ratio of diatomite to hydrochloric acid solution is (5-10)g:100ml; and the molar concentration of the hydrochloric acid solution is 1mol / L.

[0021] Preferably, the emulsifier includes one or a combination of several of octylphenol polyoxyethylene ether, dodecyl polyoxyethylene ether, and nonyl polyoxyethylene ether; and the crosslinking agent is epichlorohydrin.

[0022] Preferably, the addition amount of sodium hydroxide is 0.5-1% of the addition amount of carboxymethyl cellulose.

[0023] Preferably, the mass ratio of emulsifier to carboxymethyl cellulose is (0.8-1.1):1; and the addition amount of crosslinking agent is 3-8% of the addition amount of carboxymethyl cellulose.

[0024] Through the above technical scheme, the diatomite becomes rougher after being treated by hydrochloric acid, forms many grooves and holes, increases the surface area and specific volume of the particles, can load more microorganisms, and is beneficial to subsequent coating of carboxymethyl cellulose; the carboxymethyl cellulose is coated on the surface of the diatomite under the action of the emulsifier and the crosslinking agent, forms a gel coating layer, the metal salt is dissolved in the solution, the metal cations are fixed on the carrier by coordinating with the active groups on the carboxymethyl cellulose, and the metal cations are convenient for capturing and fixing phosphate.

[0025] Preferably, the modified diatomite surface further loads titanium dioxide.

[0026] Preferably, the modified diatomite loaded with titanium dioxide is prepared by the following method: butyl titanate is added to anhydrous ethanol, acetic acid is added after uniform stirring, and stirring is continued until a transparent light yellow liquid is formed; the modified diatomite is added to the transparent light yellow liquid, stirring and mixing are performed, nitric acid is added, the temperature is increased to 40-50 DEG C, stirring is performed for 4-6 h, and after cooling and standing for 10-12 h, the modified diatomite loaded with titanium dioxide is obtained by calcining in a muffle furnace at 500-700 DEG C for 3-4 h and then grinding and sieving.

[0027] Preferably, the mass ratio of butyl titanate to modified diatomite is (0.4-0.6):1.

[0028] Through the above technical scheme, the titanium dioxide has a photocatalytic effect, can catalytically decompose part of the carboxymethyl cellulose of the solidified phosphate by being loaded on the diatomite, the decomposed carboxymethyl cellulose is removed together with sludge by sedimentation, and the decomposed part of the carboxymethyl cellulose can serve as part of the carbon source to provide part of the energy for the microorganisms, provides the energy for growth and reproduction of the microorganisms in the low-carbon-source sewage environment, and improves the efficiency of denitrification and phosphorus removal of the microorganisms.

[0029] Preferably, the particle size of the biological synergistic carrier is 200-400 mesh.

[0030] The particle size of the biological synergistic carrier is small, the particle size of the formed sludge particles is small, the stability of the sludge particles is improved, and the mass transfer effect is excellent.

[0031] Preferably, the mass ratio of the biological synergistic carrier to the compound microbial agent is 1:(0.2-0.4).

[0032] In a second aspect, the application further provides a step of a zero-carbon-source HJDL sewage treatment method, comprising:

[0033] S1: The sewage is filtered by a grid to filter out large pieces of sundries and medium-sized sundries, and the filtered sewage flows into the front end of the HJDL tank together with the backflow sludge mixture and then flows into the HJDL reaction tank;

[0034] S2: the HJDL reaction tank includes a microbial hatching system, a stirring device and a reflux device, the mixed liquid of sewage and reflux sludge and high-concentration microorganisms enter the microbial hatching system, and under the action of the microbial hatching system, the mixed liquid is hatched into HJDL granulated sludge and sprayed from the bottom under pressure; the stirring device keeps the sludge, water and microorganisms in the HJDL reaction tank in a state of continuous movement; the reflux device pumps the existing biological synergistic carrier and composite microbial agent in the HJDL reaction tank to the top of the reactor, and continuously completes the granulation process of the granulated sludge.

[0035] S3: the water body discharged from the HJDL reaction tank enters the secondary sedimentation tank for static sedimentation, the bottom sludge in the secondary sedimentation tank is discharged, the middle layer sludge in the secondary sedimentation tank is mixed with the reflux sludge and re-enters the HJDL reaction tank for treatment, and the sewage with qualified water quality indexes after sedimentation treatment is discharged from the secondary sedimentation tank, and the sewage treatment is completed.

[0036] By adopting the above technical scheme, the sewage is treated by the HJDL reaction tank, the biological synergistic carrier contained therein can form sludge particles, and has a good removal effect on nitrogen and phosphorus in the sewage; and due to the action of the carboxymethyl cellulose-diatomite carrier, a good denitrification and phosphorus removal effect can also be achieved in the treatment process of low-carbon-source sewage.

[0037] In summary, the present application has the following beneficial effects:

[0038] 1. The biological synergistic carrier in the present application has metal ions coordinated on the surface, and after the microorganisms absorb phosphorus, the phosphate is released, and then captured by the metal ions on the surface of the carrier and subjected to a chemical reaction, so that the phosphate does not need to be deposited on the sludge carrier, thereby reducing the amount of organic carbon source required in the phosphorus removal process, increasing the utilization rate of carbon source in the sewage, and thus not needing to add additional carbon source.

[0039] 2. The diatomite has a porous structure and a large specific surface area, and has stable chemical properties, and microorganisms can be well adsorbed and survive in the diatomite interstices, providing a good living environment for a large number of anaerobic bacteria such as phosphorus accumulating bacteria; the carboxymethyl cellulose can provide a donor for the coordination reaction of metal cations and stabilize the diatomite, inhibiting the occurrence of anaerobic swelling.

[0040] 3. The modified diatomite surface can also be loaded with titanium dioxide, which has a photocatalytic effect, and by being loaded on the diatomite, it can catalyze the decomposition of part of the carboxymethyl cellulose that solidifies the phosphate, the decomposed carboxymethyl cellulose is removed together with the sludge by sedimentation, and part of the decomposed carboxymethyl cellulose can act as a part of the carbon source to provide part of the energy for the microorganisms, providing energy for the growth and reproduction of the microorganisms in the low-carbon-source sewage environment, and improving the efficiency of microbial denitrification and phosphorus removal. DETAILED DESCRIPTION

[0041] Preparation Example of Modified Diatomite Supported Titanium Dioxide

[0042] Preparation Example 1-1, a modified diatomite supported titanium dioxide, was prepared according to the following method:

[0043] 8 g of diatomite (silicon dioxide content 80%~84%) was added to 100 ml of 1 mol / L hydrochloric acid solution, soaked at 60°C for 5 h, and then filtered, washed, dried, ground, and sieved to obtain modified diatomite.

[0044] 50 g of butyl titanate was added to 200 ml of anhydrous ethanol solution, stirred until uniform, and then 10 g of acetic acid was added. The stirring was continued until a transparent light yellow liquid was formed. 100 g of the modified diatomite was added to the transparent light yellow liquid, stirred and mixed, and then 4 g of nitric acid was added. The temperature was raised to 40°C, and the stirring was continued for 6 h. After cooling and standing for 12 h, the mixture was placed in a muffle furnace and calcined at 600°C for 3 h. The modified diatomite supported titanium dioxide was obtained after grinding and sieving.

[0045] Preparation Example of Bio-enhancing Carrier

[0046] Preparation Example 2-1, a bio-enhancing carrier, was prepared according to the following method:

[0047] 100 g of diatomite (silicon dioxide content 80%~84%) was added to 1000 ml of 1 mol / L hydrochloric acid solution, soaked at 60°C for 5 h, and then filtered, washed, dried, ground, and sieved to obtain modified diatomite.

[0048] The obtained modified diatomite was dispersed in 250 ml of deionized water. 30 g of carboxymethyl cellulose (viscosity 800~1200 mpa·s) and 0.24 g of sodium hydroxide were dissolved in 100 ml of deionized water, and then added to the modified diatomite solution. The stirring and dispersion were performed, and then 30 g of octylphenol polyoxyethylene ether and 1.8 g of epichlorohydrin were added. The stirring was continued at 70°C for 2 h. The temperature was reduced to 40°C, and 6 g of aluminum chloride was added. The stirring was continued for 8 h. The bio-enhancing carrier was obtained after filtration, washing, drying, grinding, and sieving. The average particle size of the bio-enhancing carrier was 200 mesh.

[0049] Preparation Example 2-2, a bio-enhancing carrier, was prepared according to the following method. The only difference between Preparation Example 2-2 and Preparation Example 2-1 was that the modified diatomite supported titanium dioxide prepared in Preparation Example 1-1 was used instead of the modified diatomite in Preparation Example 2-1.

[0050] Preparation Example 2-3, a bio-enhancing carrier, was prepared according to the following method. The only difference between Preparation Example 2-3 and Preparation Example 2-1 was that the modified diatomite was replaced by a mixture of the modified diatomite supported titanium dioxide prepared in Preparation Example 1-1 and the modified diatomite in Preparation Example 2-1 at a mass ratio of 5:5.

[0051] Preparation Example 2-4, a bio-potentiation carrier, differs from Preparation Example 2-1 only in that the modified diatomite is the modified diatomite prepared in Preparation Example 1-1 loaded with titanium dioxide in a mass ratio of 2:8 to the modified diatomite in Preparation Example 2-1.

[0052] Preparation Examples 2-5 to 2-10, bio-potentiation carriers, differ from Preparation Example 2-1 only in that the proportions of the raw materials used are changed, the raw material formulations used being as shown in Table 1:

[0053] Table 1 Formulations of Preparation Example 2-1, Preparation Example 2-5 to Preparation Example 2-10

[0054]

[0055] The average particle size of the bio-potentiation carrier selected in Preparation Example 2-7 and Preparation Example 2-8 is 400 mesh.

[0056] Preparation Example 2-11, a bio-potentiation carrier, differs from Preparation Example 2-1 only in that the amount of carboxymethyl cellulose added is 15 g.

[0057] Preparation Example 2-12, a bio-potentiation carrier, differs from Preparation Example 2-1 only in that the amount of carboxymethyl cellulose added is 45 g.

[0058] Preparation Example 2-13, a bio-potentiation carrier, differs from Preparation Example 2-1 only in that the amount of aluminum chloride added is 2 g.

[0059] Preparation Example 2-14, a bio-potentiation carrier, differs from Preparation Example 2-1 only in that the amount of aluminum chloride added is 10 g.

[0060] Preparation Example 2-15, a bio-potentiation carrier, is prepared according to the following method:

[0061] 100 g of diatomite (silicon dioxide content 80% to 84%) is added to 1000 ml of 1 mol / L hydrochloric acid solution, and soaked at a constant temperature of 60°C for 5 h, and then filtered, washed, dried, ground and sieved to obtain modified diatomite;

[0062] The modified diatomite obtained is dispersed in 250 ml of deionized water, and then 6 g of aluminum chloride is added, the temperature is raised to 50°C, and stirring is carried out for 8 h, and then filtered, washed, dried, ground and sieved to obtain a bio-potentiation carrier. The average particle size of the bio-potentiation carrier selected is 200 mesh.

[0063] Preparation Example 2-16, a bio-potentiation carrier, is prepared according to the following method:

[0064] 100g diatomite (silicon dioxide content 80%~84%) is added into 1000ml 1mol / L hydrochloric acid solution, soaked at 60℃ for 5h, then filtered, washed, dried, grinded and sieved to obtain modified diatomite;

[0065] The obtained modified diatomite is dispersed in 250ml deionized water; 30g carboxymethyl cellulose (viscosity 800~1200mpa·s) and 0.24g sodium hydroxide are dissolved in 100ml deionized water, and then added into the modified diatomite solution, stirred and dispersed, then 30g octylphenol polyoxyethylene ether and 1.8g epichlorohydrin are added, stirred and reacted at 70℃ for 2h, then filtered, washed, dried, grinded and sieved to obtain bio-enhancing carrier. The average particle size of the obtained bio-enhancing carrier is 200 mesh.

[0066] Preparation Example 2-17, a bio-enhancing carrier, is prepared according to the following method:

[0067] 100g diatomite (silicon dioxide content 80%~84%) is added into 1000ml 1mol / L hydrochloric acid solution, soaked at 60℃ for 5h, then filtered, washed, dried, grinded and sieved to obtain bio-enhancing carrier. The average particle size of the obtained bio-enhancing carrier is 200 mesh.

[0068] Example

[0069] Example 1, a zero-carbon source HJDL sewage treatment method, the steps of the sewage treatment method are as follows:

[0070] S1: The sewage is filtered through a grid to remove large and medium-sized impurities, and the filtered sewage enters the front end of the HJDL tank and flows into the HJDL reaction tank together with the reflux sludge mixture;

[0071] S2: The HJDL reaction tank includes a microbial incubation system, a stirring device and a reflux device. The sewage and the reflux sludge mixture enter the microbial incubation system together with high-concentration microorganisms, and are incubated into HJDL granulated sludge under the action of the microbial incubation system and are sprayed from the bottom under pressure. The stirring device keeps the sludge, water and microorganisms in the HJDL reaction tank in a continuous motion state. The reflux device pumps the existing bio-enhancing carrier and composite microbial agent in the HJDL reaction tank to the top of the reactor to continuously complete the granulation process of the granulated sludge.

[0072] S3: The water discharged from the HJDL reaction tank enters the secondary sedimentation tank for static sedimentation. The bottom sludge in the secondary sedimentation tank is discharged, and the middle sludge in the secondary sedimentation tank reenters the HJDL reaction tank together with the reflux sludge mixture for treatment. The treated sewage in the secondary sedimentation tank with qualified water quality indexes is discharged, and the sewage treatment is completed.

[0073] The bio-enhancing carrier prepared in Preparation Example 2-1 and the composite microbial agent are put into the HJDL reaction tank in a mass ratio of 1:0.25. The composite microbial agent is a combined microbial agent with a mass ratio of m(composite COD bacteria):m(composite denitrifying bacteria):m(composite phosphorus accumulating bacteria):m(anaerobic bacteria) = 3:3:2:2. The composite COD bacteria include a combination of Ganda composite bacteria and COD degrading bacteria; the composite denitrifying bacteria include a combination of Bacillus subtilis, nitrifying bacteria, denitrifying bacteria, photosynthetic bacteria, and lactic acid bacteria; the composite phosphorus accumulating bacteria include a combination of Acinetobacter, Aeromonas, Corynebacterium, and Micrococcus; and the anaerobic bacteria are methanogens.

[0074] Example 2, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-2 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1.

[0075] Example 3, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-3 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1.

[0076] Example 4, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-4 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1.

[0077] Example 5, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-5 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1; and the mass ratio of the bio-enhancing carrier to the composite microbial agent is 1:0.2.

[0078] Example 6, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-6 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1; and the mass ratio of the bio-enhancing carrier to the composite microbial agent is 1:0.4.

[0079] Example 7, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-7 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1.

[0080] Example 8, a zero-carbon source HJDL sewage treatment method, differs from Example 1 only in that the bio-enhancing carrier prepared in Preparation Example 2-8 is used to replace the bio-enhancing carrier prepared in Preparation Example 2-1.

[0081] Example 9, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-9 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0082] Example 10, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-10 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0083] Example 11, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-11 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0084] Example 12, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-12 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0085] Example 13, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-13 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0086] Example 14, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-14 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0087] Comparative Example

[0088] Comparative Example 1, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-15 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0089] Comparative Example 2, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-16 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0090] Example 3, a zero-carbon source HJDL wastewater treatment method, which differs from Example 1 only in that the bioaugmentation carrier prepared in Preparation Example 2-17 is used instead of the bioaugmentation carrier prepared in Preparation Example 2-1.

[0091] Performance test test

[0092] 1. Nitrogen removal rate in low-carbon source sewage: The total nitrogen content in the sewage was determined according to HJ 636-2012 "Determination of Total Nitrogen in Water by Alkaline Persulfate Digestion UV Spectrophotometry". The total nitrogen content in the sewage before and after treatment by Examples 1-14 and Comparative Examples 1-3 was tested, and the total nitrogen removal rate was calculated, with a sewage inflow of 200 m 3 / d, a treatment time of 7 days, and the following calculation formula:

[0093]

[0094] wherein N1 refers to the total phosphorus content in the sewage before treatment, and N2 refers to the total phosphorus content in the sewage after treatment.

[0095] 2. Phosphorus removal rate in low-carbon source sewage: The total phosphorus content in the sewage was determined according to GB / T 11893-1989 "Determination of Total Phosphorus in Water by Ammonium Molybdate Spectrophotometry". The total phosphorus content in the sewage before and after treatment by Examples 1-14 and Comparative Examples 1-3 was tested, and the total phosphorus removal rate was calculated, with a sewage inflow of 200 m 3 / d, a treatment time of 7 days, and the following calculation formula:

[0096]

[0097] wherein P1 refers to the total phosphorus content in the sewage before treatment, and P2 refers to the total phosphorus content in the sewage after treatment.

[0098] The test results are shown in Table 2:

[0099] Table 2: Test results of denitrification and dephosphorization of low-carbon source sewage

[0100]

[0101] According to Table 2, in combination with Example 1 and Example 2, it can be seen that the total phosphorus removal rate and the total nitrogen removal rate of Example 2 are increased compared to Example 1, indicating that the denitrification and dephosphorization effect of Example 2 is better than that of Example 1. The reason may be that in Example 2, the biological synergistic carrier is loaded with titanium dioxide, which has a photocatalytic effect. In the process of sewage treatment, the metal ions on the biological synergistic carrier combine with the phosphate released by the phosphorus accumulating bacteria, and are decomposed from the biological synergistic carrier under the catalysis of titanium dioxide and are deposited with sludge. The decomposed carboxymethyl cellulose can also serve as a nutrient source for the growth and reproduction of microorganisms, promoting the growth of microorganisms and exhibiting good denitrification and dephosphorization effect.

[0102] In combination with Example 1, Example 2, Example 3 and Example 4, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Example 3 are the highest, and the total nitrogen removal rate and the total phosphorus removal rate of Example 4 are similar to those of Example 1, which indicates that the denitrification and phosphorus removal effect of Example 3 is the best. The reason may be that the mass ratio of the biological synergistic carrier loaded with titanium dioxide to the biological synergistic carrier not loaded with titanium dioxide in Example 3 is 5:5. Compared with the biological synergistic carrier without loading titanium dioxide, Example 3 can perform a partial catalytic decomposition reaction, and compared with the biological synergistic carrier all loaded with titanium dioxide, the speed of catalytic decomposition of Example 3 is relatively slow, which can make the reaction proceed for a long time, and the denitrification and phosphorus removal effect is more prominent.

[0103] In combination with Example 1, Example 5 to Example 10, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Example 5 to Example 10 have no obvious change compared with Example 1, which indicates that the denitrification and phosphorus removal effect of Example 5 to Example 10 is similar to that of Example 1. The reason may be that the difference between Example 5 to Example 10 and Example 1 is only that the ratio of raw materials in the preparation process of the biological synergistic carrier is changed within the required range, which indicates that changing the ratio of raw materials of the biological synergistic carrier within the required range has no obvious influence on the final denitrification and phosphorus removal effect.

[0104] In combination with Example 1, Example 11 and Example 12, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Example 11 and Example 12 decrease compared with Example 1, and the decrease of Example 11 is more obvious, which indicates that the denitrification and phosphorus removal effect of Example 11 and Example 12 is lower than that of Example 1. The origin may be that in the preparation process of the biological synergistic carrier used in Example 11, the addition amount of carboxymethyl cellulose is reduced, which reduces the content of carboxymethyl cellulose coated on the surface of diatomite and the combination points of metal ions, and reduces the denitrification and phosphorus removal effect; in the preparation process of the biological synergistic carrier used in Example 12, the addition amount of carboxymethyl cellulose is increased, and part of the carboxymethyl cellulose is prone to self-association and mutual entanglement, which reduces the stability and leads to the decrease of the final denitrification and phosphorus removal effect.

[0105] In combination with Example 1, Example 13 and Example 14, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Example 13 are decreased compared with Example 1, and the decrease of the total phosphorus removal rate is more obvious, and the total nitrogen removal rate and the total phosphorus removal rate of Example 14 have no obvious change compared with Example 1, which indicates that the denitrification and phosphorus removal effect of Example 13 is decreased compared with Example 1. The reason may be that the content of metal ions on the biological synergistic carrier used in Example 13 is reduced, the content of metal ions combined with phosphate is reduced, and the polyphosphorus bacteria and denitrifying bacteria compete for the small amount of carbon source in the sewage, so that the overall denitrification and phosphorus removal effect is reduced; the amount of metal salt added in the preparation process of the biological synergistic carrier used in Example 14 is increased, but the metal ions coordinated with carboxymethyl cellulose have reached saturation, and further addition has no good improvement on the denitrification and phosphorus removal effect.

[0106] In combination with Example 1 and Comparative Example 1, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Comparative Example 1 are obviously decreased compared with Example 1, which indicates that the denitrification and phosphorus removal effect of Comparative Example 1 is obviously decreased compared with Example 1. The reason may be that the biological synergistic carrier used in Comparative Example 1 does not add carboxymethyl cellulose, but only diatomite as the carrier. In the process of sewage treatment, diatomite will gradually form a diatomite suspension layer, and microorganisms attached to diatomite will gradually absorb organic carbon sources in sewage to meet their own growth needs. However, diatomite will swell anaerobically after adsorbing organic carbon sources, resulting in the loss of the original normal treatment effect, and finally causing the denitrification and phosphorus removal effect to decrease.

[0107] In combination with Example 1 and Comparative Example 2, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Comparative Example 2 are obviously decreased compared with Example 1, which indicates that the denitrification and phosphorus removal effect of Comparative Example 2 is obviously decreased compared with Example 1. The reason may be that the biological synergistic carrier used in Comparative Example 2 has no metal ions on the surface, and the phosphate released by the polyphosphorus bacteria can only use sludge as the carrier. However, in a low-carbon environment, the proliferation of sludge is slow, which makes it difficult to maintain a good and stable denitrification and phosphorus removal effect.

[0108] In combination with Example 1 and Comparative Example 3, it can be seen that the total nitrogen removal rate and the total phosphorus removal rate of Comparative Example 3 are obviously decreased compared with Example 1, which indicates that the denitrification and phosphorus removal effect of Comparative Example 3 is obviously decreased compared with Example 1. The reason may be that Comparative Example 3 only has diatomite as the biological synergistic carrier, and has no carboxymethyl cellulose as the stabilizer and no metal ions to provide the carrier for phosphate. In a low-carbon environment, the polyphosphorus bacteria and denitrifying bacteria compete for carbon sources, and in the absence of external carbon sources, the overall denitrification and phosphorus removal effect is greatly reduced.

[0109] The embodiments are only illustrative of the present application, and are not intended to limit the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A zero-carbon source HJDL sewage treatment method, characterized in that, The HJDL reaction tank comprises a microbial hatching system; the HJDL reaction tank is provided with a biological synergistic carrier and a composite microbial agent; the biological synergistic carrier is a carboxymethyl cellulose-diatomite carrier, and the surface of the carrier is coordinated with metal ions, wherein the metal ions comprise one or a combination of aluminum ions, divalent iron ions, calcium ions, zinc ions and copper ions; the composite microbial agent comprises one or a combination of composite denitrifying bacteria, composite phosphorus-removing bacteria and composite COD bacteria; the raw materials for the biological synergistic carrier comprise carboxymethyl cellulose, metal salt and diatomite in a mass ratio of (20-40):(3-8):100; The biological synergistic carrier is prepared by modifying diatomite, adding the diatomite into a hydrochloric acid solution, soaking at a constant temperature of 60-80 DEG C for 4-6 hours, filtering, washing to neutral, drying, grinding and passing through a 200-mesh sieve to obtain modified diatomite; The carboxymethyl cellulose-diatomite carrier is prepared by dispersing the modified diatomite in deionized water; The carboxymethyl cellulose and sodium hydroxide are dissolved in deionized water and added to the modified diatomite solution, stirred and dispersed, and then emulsifiers and crosslinking agents are added, and stirred and reacted at 60-80 DEG C for 1-2 hours; the temperature is reduced to 35-45 DEG C, metal salt is added, and stirring and reaction are continued for 6-8 hours; then filtering, washing, drying, grinding and sieving are performed to obtain the carboxymethyl cellulose-diatomite carrier; The modified diatomite is also loaded with titanium dioxide by the following method: butyl titanate is added to anhydrous ethanol, stirred uniformly, acetic acid is added, and stirring is continued until a transparent light yellow liquid is formed; the modified diatomite is added to the transparent light yellow liquid, stirred and mixed, nitric acid is added, the temperature is raised to 40-50 DEG C, stirring and reaction are continued for 4-6 hours, the mixture is cooled and allowed to stand for 10-12 hours, and then the mixture is placed in a muffle furnace and calcined at 500-700 DEG C for 3-4 hours; the modified diatomite loaded with titanium dioxide is obtained by grinding and sieving, and the mass ratio of butyl titanate to modified diatomite is (0.4-0.6):

1.

2. The zero-carbon source HJDL wastewater treatment method according to claim 1, characterized in that, The metal salt comprises one or a combination of aluminum chloride, aluminum sulfate, ferrous chloride, iron sulfate, calcium chloride, copper chloride, copper sulfate, copper nitrate and zinc chloride.

3. The zero-carbon source HJDL wastewater treatment method according to claim 1, characterized in that, The particle size of the biological synergistic carrier is 200-400 mesh.

4. The zero-carbon source HJDL wastewater treatment method according to claim 1, characterized in that, The mass ratio of the biological synergistic carrier to the composite microbial agent is 1:(0.2-0.4).

5. The zero-carbon source HJDL wastewater treatment method according to claim 1, characterized in that, The method comprises the following steps: S1: the sewage is filtered through a grid to remove large and medium-sized impurities, and the filtered sewage is mixed with a backflow sludge mixture and then flows into the HJDL reaction tank; S2: the HJDL reaction tank comprises a microbial hatching system, a stirring device and a backflow device; the sewage and the backflow sludge mixture and high-concentration microorganisms enter the microbial hatching system, and are hatched into HJDL granulated sludge under the action of the microbial hatching system and are sprayed from the bottom; the stirring device keeps the sludge, water and microorganisms in the HJDL reaction tank in a state of continuous movement; the backflow device pumps the existing biological synergistic carrier and composite microbial agent in the HJDL reaction tank to the top end of the reactor, and continuously completes the granulation process of the granulated sludge; S3: The water in the HJDL reaction tank is discharged into the secondary sedimentation tank for standing and sedimentation, the bottom sludge in the secondary sedimentation tank is discharged, the middle layer sludge in the secondary sedimentation tank is mixed with the backflow sludge to re-enter the HJDL reaction tank for treatment, the treated water in the secondary sedimentation tank is discharged, and the sewage treatment is completed.

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