A processing method for mineral-based multi-electron donor autotrophic denitrification particles

Abstract

The present application belongs to the technical field of water treatment materials. More specifically, it relates to a processing method of mineral-based multi-electron donor autotrophic denitrification particles. The specific processing steps of the present application include: uniformly mixing ferrous vitriol and autotrophic microbial bacteria suspension, centrifugal separation, obtaining denitrification self-activation precursor; adding the denitrification self-activation precursor into a sodium alginate solution, uniformly stirring and mixing, then transferring into a mold, solidifying into a colloid; soaking the colloid in a calcium chloride solution for cross-linking reaction, cold storage solidification, obtaining denitrification self-activation agent; mixing cement, pyrite, siderite, steel slag, medium-coarse sand, sodium bicarbonate and the denitrification self-activation agent, then adding a mixed solution, and granulating through a granulator, obtaining particle materials; placing the particle materials at room temperature, spraying an anionic surfactant solution on the surface of the particle materials; after the end of the static placement, drying the particle materials, and the mineral-based multi-electron donor autotrophic denitrification particles are obtained.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water treatment materials. More particularly, it relates to a processing method of mineral-based multi-electron donor autotrophic denitrification particles. BACKGROUND

[0002] Compared with traditional heterotrophic denitrification process, autotrophic denitrification process has been widely concerned due to its advantages of overcoming organic carbon source dependence and producing less sludge, and the processing of autotrophic denitrification filler has become one of the current research hotspots. At present, the production process of autotrophic denitrification filler mainly adopts normal temperature foaming or high temperature sintering, but both of these two processes have great shortcomings. The foaming agent used in normal temperature foaming is mostly physical polymer foaming agent, which introduces a new pollution source to water body, and at the same time, the strength of the filler is often limited under normal temperature foaming; the high temperature sintering method has high energy consumption and high equipment investment, and its economic feasibility is poor, which is not conducive to large-scale production. In addition, sulfur, as the first choice of electron donor, is a dangerous product with flammability and explosiveness, and its price is high and its procurement is controlled. Transportation and storage of sulfur also have great safety hazards, and the use of single donor sulfur is prone to problems such as general slow release performance and high sulfate content in effluent.

[0003] The denitrification effect of autotrophic denitrification process also depends on the types and activities of microorganisms. The denitrifying desulfurization bacteria mainly have Thiobacillus and Sulfurimonas as the genus, and use sulfide as the electron donor and NO3 - However, although the denitrifying desulfurization bacteria are widely distributed in natural ecosystems, the proportion of the genus is low due to the growth mechanism. At the same time, autotrophic denitrification denitrification has problems such as long microbial culture time, slow denitrification efficiency, high alkalinity requirement, and denitrification rate limited by the supply of electron donor. SUMMARY

[0004] The technical problem to be solved by the present application is to overcome the problems of long microbial culture time and general denitrification rate of the existing autotrophic denitrification filler, and a processing method of mineral-based multi-electron donor autotrophic denitrification particles is provided.

[0005] The purpose of the present application is to provide a processing method of mineral-based multi-electron donor autotrophic denitrification particles.

[0006] The above-mentioned purpose of the present application is achieved by the following technical solutions:

[0007] The processing method of the mineral-based multi-electron donor autotrophic denitrification particles specifically comprises the following processing steps:

[0008] After the marcasite and the autotrophic microbial bacteria suspension are uniformly mixed, centrifugal separation is performed to obtain a denitrification self-activation precursor;

[0009] The denitrification self-activation precursor is added into a sodium alginate solution, stirred and mixed uniformly, and then transferred into a mold to solidify into a gel;

[0010] After the gel is immersed in a calcium chloride solution for cross-linking reaction and cold storage solidification, a denitrification self-activator is obtained;

[0011] After cement, pyrite, siderite, steel slag, medium-coarse sand, sodium bicarbonate and the denitrification self-activator are uniformly mixed, a mixed solution is added, and granulation is performed through a granulator, a granular material is obtained; the mixed solution is obtained by dissolving ferrous sulfate heptahydrate and sodium thiosulfate pentahydrate in water;

[0012] The granular material is placed at room temperature for 3-5 days, and during the placement process, an anionic surfactant solution is sprayed on the surface of the granular material every 4-8 hours;

[0013] After the placement is completed, the granular material is dried at a temperature of 45-60 DEG C for 4-6 hours, and then discharged, and a mineral-based multi-electron donor autotrophic denitrification granule is obtained.

[0014] The beneficial effects of the above technical solutions are:

[0015] The autotrophic denitrifying microorganisms are widely distributed in nature but account for a low proportion, and the growth rate of the autotrophic denitrifying microorganisms is far lower than that of the heterotrophic microorganisms, so under natural domestication, the proliferation rate of the autotrophic denitrifying microorganisms is slow, and the biofilm formation period is long. Therefore, the denitrification self-activator and the microbial activation additive which is beneficial to the growth of the autotrophic denitrifying microorganisms are added, the denitrification self-activator has a slow-release performance, provides necessary nutrient conditions and bacterial base for the proliferation of the autotrophic denitrifying microorganisms, and is beneficial to the rapid activation of the autotrophic denitrification reaction. Meanwhile, the introduction of the mineral-based multi-electron donor can effectively promote the metabolic coupling of the microorganisms, realize the self-activation of the denitrification reaction process, and solve the difficulties of low electron donor supply rate and slow microbial enrichment efficiency;

[0016] Especially, it is necessary to note that by selecting sodium alginate and calcium chloride, a cross-linked sodium alginate macromolecular gel network is formed, and the denitrification self-activation precursor is effectively fixed, so that it can be stably and continuously supplied;

[0017] The single electron donor pyrite has natural adverse characteristics, and the dissolution rate of the pyrite is slow, so the pyrite, white iron ore and siderite are introduced as multi-electron donors to construct a cooperative denitrification system mainly based on iron autotrophic denitrification and supplemented by sulfur autotrophic denitrification, effectively improve the deficiencies of different electron donors, and utilize the characteristics that the white iron ore and the siderite can be quickly utilized due to high microbial affinity and the sulfur sulfate yield of the pyrite is low. In addition, the reaction product iron ion can generate iron phosphate precipitate with phosphate in wastewater, so the denitrification also has a phosphorus removal effect;

[0018] The cement can greatly improve the strength of the mineral-based multi-electron donor autotrophic denitrification particle, and can also tightly combine each component with the cement skeleton to form a slow-release structure, which is beneficial to the gradual slow release of each component, so that the mineral-based multi-electron donor autotrophic denitrification particle has slow-release performance.

[0019] Further, the anionic surfactant solution is selected from any one of the following: a sodium fatty acid solution, a sodium laurate solution, a sodium dodecyl benzene sulfonate solution, a sodium dodecyl sulfate solution, a sodium alpha-olefin sulfonate solution, a sodium lauryl sulfate solution, and a sodium succinate sulfonate solution.

[0020] Further, the mass fraction of the anionic surfactant solution is 4-8%.

[0021] The technical scheme has the following beneficial effects:

[0022] Further, the anionic surfactant solution is sprayed during the standing process of the granular material, which can provide water for the hydration process of the cement, and can also help the formation of a high porosity on the surface of the granular material under the action of the generated heat and the anionic surfactant, so that the subsequent solution can be fully diffused and penetrated into the interior, the cement can be fully hydrated, and the mass transfer process during the use of the subsequent product can be facilitated.

[0023] Further, the anionic surfactant solution further comprises 10-15% of gelatin by mass of the anionic surfactant.

[0024] The isoelectric point of the gelatin is 7.0.

[0025] The technical scheme has the following beneficial effects:

[0026] The use of the gelatin can not only form a wet liquid film on the surface of the granular material after the spraying of the anionic surfactant solution, but also can cause the ionization of the carboxyl groups in the molecular structure of the gelatin under the alkaline environment of the cement system due to the suitable isoelectric point of the gelatin, so that the gelatin molecules are expanded due to the mutual repulsion of the same charges, and thus the pores on the surface of the granular material can be well supported to avoid the closure or collapse of the pores under the action of the hydration heat of the cement.

[0027] Further, the mass ratio of the white iron ore to the autotrophic microbial bacteria suspension is 2-3:1.

[0028] Further, the autotrophic microbial bacteria suspension comprises the following raw materials by weight: 4-6 parts of Thiobacillus denitrificans, 3-5 parts of Sulfomonas, and 100-110 parts of water.

[0029] Further, the mass ratio of the denitrification self-activation precursor and the sodium alginate solution is 1:8-10.

[0030] Further, the mass fraction of the sodium alginate solution is 2-5%.

[0031] The mass fraction of the calcium chloride solution is 2-4%.

[0032] Further, the refrigeration solidification comprises: standing and refrigerating for 12-24 hours at a temperature of 0-4℃.

[0033] Further, the specific processing step further comprises:

[0034] According to weight parts, 12-21 parts of cement, 8-13 parts of pyrite, 2-5 parts of siderite, 0.5-1.5 parts of steel slag, 3-6 parts of medium-coarse sand, 0.5-1 part of sodium bicarbonate and 1.5-4.5 parts of denitrification self-activation agent are uniformly mixed, then 8-15 parts of mixed solution is added, and granulation is performed through a granulator to obtain granular material.

[0035] Further, the mixed solution is mixed by ferrous sulfate heptahydrate, sodium thiosulfate pentahydrate and water according to a mass ratio of 2:1:100.

[0036] Further, the specific processing step further comprises:

[0037] The granular material is placed at room temperature for 3-5 days, and during the placing process, anionic surfactant solution is sprayed on the surface of the granular material every 4-8 hours.

[0038] The quality of the anionic surfactant solution sprayed each time is 4-6% of the quality of the granular material.

[0039] Further, the particle size of the pyrite is 100-200 mesh, the total content of sulfur and iron is ≥60%, and the arsenic content is ≤0.04%.

[0040] The particle size of the siderite is 100-200 mesh, the total content of iron and carbon is ≥35%, and the arsenic content is ≤0.04%.

[0041] The steel slag is converter slag, and the particle size is ≤200 mesh.

[0042] The particle size of the white iron is 100-200 mesh, the total content of sulfur and iron is ≥60%, and the arsenic content is ≤0.04%. DETAILED DESCRIPTION

[0043] The application will be further described below in combination with specific embodiments, but the embodiments do not limit the application in any form. Unless otherwise specified, the reagents, methods and devices used in the application are conventional reagents, methods and devices in the technical field.

[0044] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0045] Example 1

[0046] After mixing the marcasite and the suspension of autotrophic microbial bacteria, the mixture is continuously stirred at a speed of 80 r / min by a stirrer for 2 h, and then centrifuged to obtain the denitrification self-activation precursor;

[0047] The mass ratio of the marcasite to the suspension of autotrophic microbial bacteria is 2:1;

[0048] Furthermore, the suspension of autotrophic microbial bacteria comprises the following raw materials in parts by weight: 4 parts of Thiobacillus denitrificans, 3 parts of Sulfococcus, and 100 parts of water;

[0049] The denitrification self-activation precursor is added to a sodium alginate solution, and after stirring and mixing the mixture at a speed of 200 r / min by a stirrer for 40 min, the mixture is transferred into a 0.3 mm granular mold, and then left to solidify into a gel;

[0050] The gel is soaked in a calcium chloride solution, and after standing for cross-linking reaction at room temperature for 0.5 h, the gel is left to solidify at a temperature of 0℃ for 12 h to obtain the denitrification self-activation agent;

[0051] The mass ratio of the denitrification self-activation precursor to the sodium alginate solution is 1:8;

[0052] Furthermore, the mass fraction of the sodium alginate solution is 2%;

[0053] The mass fraction of the calcium chloride solution is 2%;

[0054] According to parts by weight, 12 parts of 42.5# ordinary Portland cement, 8 parts of pyrite, 2 parts of siderite, 0.5 part of steel slag, 3 parts of medium-coarse sand, 0.5 part of sodium bicarbonate, and 1.5 parts of the denitrification self-activation agent are uniformly mixed, and then 8 parts of a mixed solution is added, and granulated by a granulator, and the granules with a particle size distribution of 8-15 mm are screened out to obtain the granular material; the mixed solution is prepared by mixing ferrous sulfate heptahydrate, sodium thiosulfate pentahydrate, and water at a mass ratio of 2:1:100;

[0055] The granular material is left to stand at room temperature for 3 d, and during the standing process, an anionic surfactant solution is sprayed on the surface of the granular material every 4 h; the mass of the anionic surfactant solution sprayed each time is 4% of the mass of the granular material;

[0056] The anionic surfactant solution is selected from the group consisting of a sodium fatty acid solution;

[0057] And the mass fraction of the anionic surfactant solution is 4%; the mass fraction is the mass fraction of the anionic surfactant;

[0058] The anionic surfactant solution also includes 10% of the mass of the anionic surfactant as gelatin;

[0059] The isoelectric point of the gelatin is 7.0;

[0060] After the standing is finished, the granular material is dried at a temperature of 45 DEG C for 4h, and then discharged, to obtain the mineral-based multi-electron donor autotrophic denitrification granules;

[0061] The particle size of the pyrite is 100 mesh, the total content of sulfur and iron is greater than or equal to 60%, and the arsenic content is less than or equal to 0.04%;

[0062] The particle size of the siderite is 100 mesh, the total content of iron and carbon is greater than or equal to 35%, and the arsenic content is less than or equal to 0.04%;

[0063] The steel slag is converter slag, and the particle size is 200 mesh;

[0064] The particle size of the marcasite is 100 mesh, the total content of sulfur and iron is greater than or equal to 60%, and the arsenic content is less than or equal to 0.04%.

[0065] Example 2

[0066] After the marcasite and the autotrophic microbial bacteria suspension are mixed, the mixture is continuously stirred by a stirrer at a speed of 100r / min for 3h, and then centrifuged to obtain the denitrification self-activation precursor;

[0067] The mass ratio of the marcasite to the autotrophic microbial bacteria suspension is 2.5:1;

[0068] And the autotrophic microbial bacteria suspension includes the following raw materials in parts by weight: 5 parts of Thiobacillus denitrificans, 4 parts of Sulfococcus, and 105 parts of water;

[0069] The denitrification self-activation precursor is added to the sodium alginate solution, and then stirred by a stirrer at a speed of 260r / min for 50min, and then transferred into a 0.4mm granular mold, and then allowed to stand and solidify into a colloid;

[0070] The colloid is soaked in a calcium chloride solution, and then allowed to stand and crosslink at room temperature for 0.8h, and then allowed to stand and solidify at a temperature of 2 DEG C for 18h to obtain the denitrification self-activation agent;

[0071] The mass ratio of the denitrification self-activation precursor to the sodium alginate solution is 1:9;

[0072] And the mass fraction of the sodium alginate solution is 4%;

[0073] The mass fraction of the calcium chloride solution is 3%;

[0074] According to weight parts, 18 parts of 42.5# ordinary Portland cement, 10 parts of pyrite, 4 parts of siderite, 0.9 parts of steel slag, 4 parts of medium-coarse sand, 0.8 parts of sodium bicarbonate and 3.5 parts of denitrification self-activator are uniformly mixed, then 12 parts of mixed solution are added, and granulation is carried out through a granulator, and particles with a particle size distribution of 8-15mm are screened out to obtain granular materials; the mixed solution is prepared by mixing ferrous sulfate heptahydrate, sodium thiosulfate pentahydrate and water in a mass ratio of 2:1:100;

[0075] The granular materials are placed at room temperature for 4d, and during the placing process, an anionic surfactant solution is sprayed on the surface of the granular materials every 6h; the mass of the anionic surfactant solution sprayed each time is 5% of the mass of the granular materials;

[0076] The anionic surfactant solution is selected from the group consisting of sodium dodecyl benzene sulfonate solution;

[0077] And the mass fraction of the anionic surfactant solution is 6%; the mass fraction is the mass fraction of the anionic surfactant;

[0078] The anionic surfactant solution further comprises 12% of gelatin by mass of the anionic surfactant;

[0079] The isoelectric point of the gelatin is 7.0;

[0080] After the placing is completed, the granular materials are dried at a temperature of 50℃ for 5h, and then discharged to obtain mineral-based multi-electron donor autotrophic denitrification granules;

[0081] The particle size of the pyrite is 180 mesh, the total content of sulfur and iron is ≥60%, and the arsenic content is ≤0.04%;

[0082] The particle size of the siderite is 180 mesh, the total content of iron and carbon is ≥35%, and the arsenic content is ≤0.04%;

[0083] The steel slag is converter slag, and the particle size is 180 mesh;

[0084] The particle size of the white iron ore is 180 mesh, the total content of sulfur and iron is ≥60%, and the arsenic content is ≤0.04%.

[0085] Example 3

[0086] After the white iron ore and the autotrophic microbial suspension are mixed, the mixture is continuously stirred and mixed by a stirrer at a speed of 120r / min for 4h, and then centrifuged to obtain a denitrification self-activation precursor;

[0087] The mass ratio of the white iron ore and the autotrophic microbial bacteria suspension is 3:1;

[0088] The autotrophic microbial bacteria suspension comprises the following raw materials by weight: 6 parts of Thiobacillus denitrificans, 5 parts of Sulfolobus, and 110 parts of water;

[0089] The denitrification self-activation precursor is added to the sodium alginate solution, and after stirring and mixing for 60 min at a stirring speed of 300 r / min, the mixture is transferred into a 0.5 mm granular mold and left to solidify into a gel;

[0090] The gel is soaked in a calcium chloride solution, and after standing for cross-linking reaction at room temperature for 1 h, the gel is left to solidify at a temperature of 4℃ for 24 h to obtain the denitrification self-activation agent;

[0091] The mass ratio of the denitrification self-activation precursor and the sodium alginate solution is 1:10;

[0092] The mass fraction of the sodium alginate solution is 5%;

[0093] The mass fraction of the calcium chloride solution is 4%;

[0094] The following are uniformly mixed by weight fraction: 21 parts of 42.5# ordinary Portland cement, 13 parts of pyrite, 5 parts of siderite, 1.5 parts of steel slag, 6 parts of medium-coarse sand, 1 part of sodium bicarbonate, and 4.5 parts of the denitrification self-activation agent, and then 15 parts of a mixed solution is added, granulated by a granulator, and sieved to obtain granular materials with a particle size distribution of 8-15 mm; the mixed solution is prepared by mixing ferrous sulfate heptahydrate, sodium thiosulfate pentahydrate, and water at a mass ratio of 2:1:100;

[0095] The granular materials are left to stand at room temperature for 5 d, and during the standing process, an anionic surfactant solution is sprayed on the surface of the granular materials every 8 h; the mass of the anionic surfactant solution sprayed each time is 6% of the mass of the granular materials;

[0096] The anionic surfactant solution is selected from the group consisting of sodium lauryl sulfate solution;

[0097] The mass fraction of the anionic surfactant solution is 8%; the mass fraction refers to the mass fraction of the anionic surfactant;

[0098] The anionic surfactant solution further comprises 15% of gelatin by mass of the anionic surfactant;

[0099] The isoelectric point of the gelatin is 7.0;

[0100] After the standing is finished, the granular material is dried at 60℃ for 6h, and then discharged to obtain the mineral-based multi-electron donor autotrophic denitrification granules;

[0101] The pyrite has a particle size of 200 mesh, a total content of sulfur and iron of ≥60%, and an arsenic content of ≤0.04%;

[0102] The siderite has a particle size of 200 mesh, a total content of iron and carbon of ≥35%, and an arsenic content of ≤0.04%;

[0103] The steel slag has a particle size of 80 mesh;

[0104] The marcasite has a particle size of 200 mesh, a total content of sulfur and iron of ≥60%, and an arsenic content of ≤0.04%.

[0105] Example 4

[0106] Compared with Example 1, the difference is that no gelatin is added, and the other conditions remain unchanged.

[0107] Example 5

[0108] Compared with Example 1, the difference is that the isoelectric point of the gelatin is 8.0, and the other conditions remain unchanged.

[0109] Example 6

[0110] Compared with Example 1, the difference is that no anionic surfactant is added, and the other conditions remain unchanged.

[0111] Comparative Example 1

[0112] After the sepiolite and the autotrophic microbial bacteria suspension are mixed, the mixture is continuously stirred at a speed of 80r / min for 2h by using a stirrer, and then centrifuged to obtain the denitrification self-activation precursor;

[0113] The mass ratio of the sepiolite to the autotrophic microbial bacteria suspension is 2:1;

[0114] Furthermore, the autotrophic microbial bacteria suspension comprises the following raw materials in parts by weight: 4 parts of Thiobacillus denitrificans, 3 parts of Sulfococcus, and 100 parts of water;

[0115] According to parts by weight, 12 parts of 42.5# ordinary Portland cement, 8 parts of pyrite, 2 parts of siderite, 0.5 part of steel slag, 3 parts of medium-coarse sand, 0.5 part of sodium bicarbonate, and 1.5 parts of denitrification self-activation precursor are uniformly mixed, then 8 parts of a mixed solution is added, and granulation is performed by using a granulator, and granules with a particle size distribution of 8-15mm are screened out to obtain a granular material; the mixed solution is prepared by mixing ferrous sulfate heptahydrate, sodium thiosulfate pentahydrate, and water in a mass ratio of 2:1:100;

[0116] The particulate material is placed at room temperature for 3d, and during the placement, the surface of the particulate material is sprayed with an anionic surfactant solution every 4h; the mass of the anionic surfactant solution sprayed each time is 4% of the mass of the particulate material;

[0117] The anionic surfactant solution is selected from the group consisting of a sodium fatty acid solution;

[0118] The mass fraction of the anionic surfactant solution is 4%; the mass fraction refers to the mass fraction of the anionic surfactant;

[0119] The anionic surfactant solution further comprises gelatin in an amount of 10% of the mass of the anionic surfactant;

[0120] The isoelectric point of the gelatin is 7.0;

[0121] After the placement is completed, the particulate material is dried at a temperature of 45℃ for 4h, and then discharged to obtain the mineral-based multi-electron donor autotrophic denitrification granules;

[0122] The particle size of the pyrite is 100 mesh, the total content of sulfur and iron is ≥60%, and the arsenic content is ≤0.04%;

[0123] The particle size of the siderite is 100 mesh, the total content of iron and carbon is ≥35%, and the arsenic content is ≤0.04%;

[0124] The type of the steel slag is converter slag, and the particle size is 200 mesh.

[0125] The products obtained in the examples and comparative examples are subjected to performance testing, and the specific testing methods and testing results are as follows:

[0126] 1000mL anaerobic bottles are selected as the test devices, and the products obtained in the examples and comparative examples are respectively added to the corresponding anaerobic bottles. 500mL of simulated water samples are added to each anaerobic bottle in advance, and the content of NO3 - The content of -N is 30mg / L, which is adjusted by sodium nitrate; the concentrations of other inclusions are as follows: sodium bicarbonate 0.1g / L, disodium hydrogen phosphate 0.004g / L, which are prepared by using municipal tap water and adjusting the pH to 7.0;

[0127] The anaerobic bottles are fully exposed to nitrogen gas, and the liquid surface is aerated for 15min, and the top air is aerated for 5min to provide an anaerobic environment for the reaction system. After the rubber plug is inserted, a sampling needle with a three-way valve is inserted to facilitate sampling;

[0128] Every 24h, 2.5mL of sample is taken, and the temperature is 30℃, the rotation speed is 60rpm, and the constant temperature oscillation shaker is continuously operated for 4d; during the process, the content of NO3 -The removal rate of N is shown in Table 1:

[0129] Table 1: Product performance test results

[0130]

[0131] From the test results in Table 1, the product obtained in the application can not only remove NO3 - The content of N is significantly removed, and the treatment efficiency is high.

[0132] The above examples are the preferred embodiments of the application, but the embodiments of the application are not limited to the above examples, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the application should be equivalent replacement methods, and are included in the protection scope of the application.

Claims

1. A method for processing mineral-based multi-electron donor autotrophic denitrification particles, characterized in that: The specific processing steps include: After the marcasite and the autotrophic microbial suspension are evenly mixed, the mixture is centrifuged to obtain a denitrification self-activation precursor; Add the denitrification self-activating precursor to the sodium alginate solution, stir and mix evenly, transfer it into a mold, and solidify it into a colloid; The colloid is immersed in a calcium chloride solution for cross-linking reaction, and then refrigerated and solidified to obtain a denitrification self-activator; Cement, pyrite, siderite, steel slag, medium-coarse sand, sodium bicarbonate and denitrification self-activator are mixed evenly, and then a mixed solution is added, and granulated by a granulator to obtain a granular material; the mixed solution is obtained by dissolving ferrous sulfate heptahydrate and sodium thiosulfate pentahydrate in water; The granular material is placed at room temperature for 3-5 days. During the placement process, an anionic surfactant solution is sprayed on the surface of the granular material every 4-8 hours; After the static placement is completed, the granular material is dried at a temperature of 45-60°C for 4-6 hours, and the material is discharged to obtain the mineral-based multi-electron donor autotrophic denitrification granules; The anionic surfactant solution is selected from any one of: sodium laurate solution, sodium dodecylbenzenesulfonate solution, sodium lauryl sulfate solution, sodium α-olefin sulfonate solution, sodium lauryl sulfate solution, and sodium sulfosuccinate solution; Furthermore, the mass fraction of the anionic surfactant solution is 4-8%; The mass of the anionic surfactant solution sprayed each time is 4-6% of the mass of the granular material; The anionic surfactant solution further comprises gelatin in an amount of 10-15% by weight of the anionic surfactant; The isoelectric point of the gelatin is 7.

0.

2. The method for processing a mineral-based multi-electron donor autotrophic denitrification particle according to claim 1, characterized in that: The mass ratio of the marcasite to the autotrophic microbial suspension is 2-3:1; Furthermore, the autotrophic microbial suspension comprises the following raw materials in parts by weight: 4-6 parts of denitrifying Thiobacillus, 3-5 parts of Thiomonas, and 100-110 parts of water.

3. The method for processing a mineral-based multi-electron donor autotrophic denitrification particle according to claim 1, characterized in that: The mass ratio of the denitrification self-activating precursor to the sodium alginate solution is 1:8-10; Furthermore, the mass fraction of the sodium alginate solution is 2-5%; The mass fraction of the calcium chloride solution is 2-4%.

4. The method for processing a mineral-based multi-electron donor autotrophic denitrification particle according to claim 1, characterized in that: The cold storage and curing comprises: standing and curing at a temperature of 0-4° C. for 12-24 hours.

5. The method for processing a mineral-based multi-electron donor autotrophic denitrification particle according to claim 1, characterized in that: The specific processing steps also include: According to weight parts, 12-21 parts of cement, 8-13 parts of pyrite, 2-5 parts of siderite, 0.5-1.5 parts of steel slag, 3-6 parts of medium-coarse sand, 0.5-1 part of sodium bicarbonate and 1.5-4.5 parts of denitrification self-activator are mixed evenly, and then 8-15 parts of the mixed solution are added, and granulated by a granulator to obtain granular material.

6. The method for processing a mineral-based multi-electron donor autotrophic denitrification particle according to claim 1, characterized in that: The mixed solution is prepared by mixing ferrous sulfate heptahydrate, sodium thiosulfate pentahydrate and water in a mass ratio of 2:1:

100.

7. The method for processing a mineral-based multi-electron donor autotrophic denitrification particle according to claim 1, characterized in that: The pyrite has a particle size of 100-200 mesh, a total sulfur and iron content of ≥60%, and an arsenic content of ≤0.04%; The siderite has a particle size of 100-200 mesh, a total iron and carbon content of ≥35%, and an arsenic content of ≤0.04%; The steel slag is converter slag with a particle size of ≤200 mesh; The particle size of the marcasite is 100-200 meshes, the total content of sulfur and iron is ≥60%, and the arsenic content is ≤0.04%.

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