A denitrifying sulfur-iron composite filler catalyst and its preparation method

Abstract

The present invention is applicable to the technical field of sewage treatment, and provides a denitrifying sulfur-iron composite packing catalyst and a preparation method thereof, which include material A and material B. Material A is a strain; material B includes a microporous aggregate, a coating material and a starch layer; the microporous aggregate includes activated carbon, sponge iron, silicon sulfide and silicon carbide; the coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder; the mass ratio of material A to material B is (1-3):(50-90); preferably, the strain includes Thiobacillus denitrificans, sulfur bacteria and a culture medium, and the contents of Thiobacillus denitrificans and sulfur bacteria in the culture medium are (1-5)×10<supgt;10< / supgt> CFU / ml and (0.5-1.5)×10<supgt;10< / supgt> CFU / ml; the components and contents of the culture medium are as follows: 1-2 g of ammonium chloride, 2-5 g of sodium sulfite, 1-2 g of potassium dihydrogen phosphate, 0.5-1 g of sodium chloride, 0.1-0.2 g of calcium sulfate, and 1 L of water. The catalyst prepared by the present invention is used for sewage treatment, not only has a high denitrification efficiency, but also has a certain reusability, is economical, environmentally friendly and has a low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and specifically to a denitrifying sulfur-iron composite packing catalyst and a preparation method thereof. Background Art

[0002] Sewage treatment refers to the process of removing or transforming harmful substances in sewage through a series of physical, chemical, and biological methods to make it meet the discharge standards or be reusable. The main goal of sewage treatment is to reduce environmental pollution, protect water resources, and ensure public health.

[0003] There are various sewage treatment methods, which can be selected according to the nature of sewage, treatment requirements, and discharge standards. Common sewage treatment methods mainly include three categories: physical methods, chemical methods, and biological methods. Physical methods mainly remove suspended solids and particulate matter in sewage through physical and mechanical means and are usually used for the primary treatment of sewage; chemical methods mainly use chemical reactions to remove pollutants in sewage and are suitable for treating dissolved substances in water; biological methods degrade organic matter in water through the metabolic action of microorganisms and are one of the main means of treating sewage.

[0004] Most of the existing biological treatment methods are nitrification denitrification, which requires a relatively high dissolved oxygen concentration, as well as suitable temperature and pH values. Since it is an aerobic reaction, the nitrification process consumes a large amount of oxygen, increasing the treatment cost. In response to this, the present application proposes a denitrifying sulfur-iron composite packing catalyst and a preparation method thereof. Summary of the Invention

[0005] The purpose of the present invention is to provide a denitrifying sulfur-iron composite packing catalyst and a preparation method thereof to solve the problems in the prior art that nitrification denitrification requires a relatively high dissolved oxygen concentration, as well as suitable temperature and pH values, and since it is an aerobic reaction, the nitrification process consumes a large amount of oxygen, increasing the treatment cost.

[0006] To achieve the above purpose, the present invention provides the following technical solution: In the first aspect of the present invention, a denitrifying sulfur-iron composite packing catalyst is proposed, which includes material A and material B. Material A is a strain; material B includes a microporous aggregate, a coating material, and a starch layer;

[0007] The microporous aggregate includes activated carbon, sponge iron, silicon sulfide, and silicon carbide;

[0008] The coating material includes a carbon source, a nitrogen source, sulfur powder, and iron powder;

[0009] The mass ratio of material A to material B is (1 - 3):(50 - 90).

[0010] Preferably, the bacterial strains include Thiobacillus denitrificans, sulfur bacteria and a culture medium, and the contents of Thiobacillus denitrificans and sulfur bacteria in the culture medium are (1-5)×10 10 CFU / ml and (0.5-1.5)×10 10 CFU / ml.

[0011] Preferably, the components and contents of the culture medium are as follows:

[0012] Ammonium chloride 1-2 g, sodium sulfite 2-5 g, potassium dihydrogen phosphate 1-2 g, sodium chloride 0.5-1 g, calcium sulfate 0.1-0.2 g, water 1 L.

[0013] Preferably, the carbon source in the coating material is glucose and the nitrogen source is nitrite.

[0014] Preferably, the microporous aggregate is coated on the outside of the coating material, and the starch layer is coated on the outside of the microporous aggregate.

[0015] Preferably, the mass ratio of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregate is (0.2-0.8):(0.5-1.5):(1-2.7):(1.4-1.8).

[0016] Preferably, the mass ratio of the carbon source, nitrogen source, sulfur powder and iron powder in the coating material is:

[0017] (0.4-1):(0.6-1.3):(1-2.6):(1.2-2).

[0018] Preferably, the coating material further contains trace elements, and the mass ratio of the trace elements is 3-6% of the whole coating material.

[0019] Preferably, the trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

[0020] The second aspect of the present invention provides a preparation method of the catalyst described in the first aspect of the present invention, comprising the following steps:

[0021] Weigh the coating material in proportion, then weigh the microporous aggregate, add an appropriate amount of water and mix, dissolve and stir, coat it on the outer layer of the coating material, and then prepare a starch film to coat on the outer layer of the microporous aggregate to obtain Material B;

[0022] Obtain Material A through biological culture;

[0023] Pack Material A and Material B separately and mix them during use.

[0024] The present invention has at least the following beneficial effects:

[0025] A denitrifying sulfur-iron composite packing catalyst provided by the present invention and its preparation method. The prepared catalyst is used for sewage treatment, not only has high denitrification efficiency, but also has certain reusability, is economical, environmentally friendly and has low cost. Description of the Drawings

[0026] Figure 1 It is the electron micrograph of the composite packing catalyst obtained in Example 3 of the present invention. Detailed Embodiments

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] The present invention provides a denitrifying sulfur-iron composite packing catalyst, which includes Material A and Material B. Material A is bacterial strains; Material B includes microporous aggregates, coating materials and starch layers; the microporous aggregates include activated carbon, sponge iron, silicon sulfide and silicon carbide; the coating materials include carbon sources, nitrogen sources, sulfur powder and iron powder; the mass ratio of Material A to Material B is (1-3):(50-90).

[0029] Further, the bacterial strains include Thiobacillus denitrificans, sulfur bacteria and culture medium. The contents of Thiobacillus denitrificans and sulfur bacteria in the culture medium are (1-5)×10 10 CFU / ml and (0.5-1.5)×10 10 CFU / ml.

[0030] Further, the components and contents of the culture medium are as follows:

[0031] Ammonium chloride 1-2g, sodium sulfite 2-5g, potassium dihydrogen phosphate 1-2g, sodium chloride 0.5-1g, calcium sulfate 0.1-0.2g, water 1L.

[0032] Further, the carbon source in the coating material is glucose and the nitrogen source is nitrite.

[0033] Further, the microporous aggregates are coated on the outside of the coating material, and the starch layer is coated on the outside of the microporous aggregates.

[0034] Further, the mass ratio of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregates is (0.2-0.8):(0.5-1.5):(1-2.7):(1.4-1.8).

[0035] Further, the mass ratio of the carbon source, nitrogen source, sulfur powder and iron powder in the coating material is (0.4-1):(0.6-1.3):(1-2.6):(1.2-2).

[0036] Furthermore, the coating material further contains trace elements, and the mass ratio of the trace elements is 3-6% of the whole coating material; the trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

[0037] The preparation method of the above catalyst includes the following steps:

[0038] Weigh the coating material in proportion, then weigh the microporous aggregate, add an appropriate amount of water and mix, dissolve and stir, coat it on the outer layer of the coating material, and then prepare a starch film to coat on the outer layer of the microporous aggregate to obtain Material B;

[0039] Obtain Material A through biological cultivation;

[0040] Pack Material A and Material B separately and mix them during use.

[0041] In the present invention, activated carbon can adsorb organic matters and impurities in sewage due to its high specific surface area and excellent adsorption capacity; sponge iron provides the iron element required for the reaction, participates in the reduction reaction, and promotes the removal of nitrogen; silicon sulfide and silicon carbide can enhance the mechanical strength and stability of the filler, and at the same time provide a microporous structure, which is beneficial to the attachment and growth of microorganisms; glucose and nitrite in the coating material provide carbon source and nitrogen source for microorganisms respectively, and sulfur powder and iron powder participate in the sulfur cycle and the redox reaction of iron, promoting the denitrification process; the starch layer as the outer coating can protect the internal microporous aggregate and coating material, prevent them from being damaged under the scouring of water flow, and at the same time provide an additional carbon source for microorganisms to utilize.

[0042] The present invention can effectively reduce the dissolved oxygen demand in the sewage treatment process, remove nitrogen elements through denitrification, reduce oxygen consumption, and thus reduce the treatment cost. In addition, the strains in the catalyst can work effectively within a relatively low temperature and a wide pH value range, improving the adaptability and flexibility of sewage treatment. At the same time, the combined design of the microporous aggregate and the coating material enhances the overall stability and durability of the filler, enabling the catalyst to have a long service life and high treatment efficiency in the sewage treatment process, and improving the reuse rate. In summary, the present invention provides an efficient, economical and environmentally friendly solution for the sewage treatment field.

[0043] Based on the above technical solutions, the present invention provides the following partial embodiments: Example 1

[0044] This example provides a denitrifying sulfur-iron composite packing catalyst, including Material A and Material B.

[0045] ①. Material A is strains:

[0046] The bacterial strains include Thiobacillus denitrificans, sulfur bacteria and a culture medium. The contents of Thiobacillus denitrificans and sulfur bacteria in the culture medium are 1×10 10 CFU / ml and 0.5×10 10 CFU / ml;

[0047] The components and contents of the culture medium are as follows:

[0048] Ammonium chloride 1g, sodium sulfite 2g, potassium dihydrogen phosphate 1g, sodium chloride 0.5g, calcium sulfate 0.1, water 1L.

[0049] ②. Material B includes microporous aggregate, coating material and starch layer. The microporous aggregate is coated outside the coating material, and the starch layer is coated outside the microporous aggregate:

[0050] The microporous aggregate includes activated carbon, sponge iron, silicon sulfide and silicon carbide; the mass ratio of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregate is 0.2:0.5:1:1.4;

[0051] The coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder. The carbon source is glucose, and the nitrogen source is nitrite; the mass ratio of the carbon source, nitrogen source, sulfur powder and iron powder in the coating material is 0.4:0.6:1:1.2.

[0052] The mass ratio of Material A to Material B is 1:50. Example 2

[0053] This example provides a denitrifying sulfur-iron composite filler catalyst, which includes Material A and Material B.

[0054] ①. Material A is bacterial strains:

[0055] The bacterial strains include Thiobacillus denitrificans, sulfur bacteria and a culture medium. The contents of Thiobacillus denitrificans and sulfur bacteria in the culture medium are 3×10 10 CFU / ml and 1×10 10 CFU / ml;

[0056] The components and contents of the culture medium are as follows:

[0057] Ammonium chloride 1.5g, sodium sulfite 3g, potassium dihydrogen phosphate 1.5g, sodium chloride 0.8g, calcium sulfate 0.15g, water 1L.

[0058] ②. Material B includes microporous aggregate, coating material and starch layer. The microporous aggregate is coated outside the coating material, and the starch layer is coated outside the microporous aggregate:

[0059] The microporous aggregate includes activated carbon, sponge iron, silicon sulfide and silicon carbide; the mass ratio of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregate is 0.6:1:2.1:1.5;

[0060] The coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder. The carbon source is glucose and the nitrogen source is nitrite. The mass ratio of the carbon source, nitrogen source, sulfur powder and iron powder in the coating material is 0.7:1:1.8:1.4.

[0061] The mass ratio of material A to material B is 2:73. Example 3

[0062] This example provides a denitrifying sulfur-iron composite packing catalyst, which includes material A and material B.

[0063] ①. Material A is the strain:

[0064] The strain includes Thiobacillus denitrificans, sulfur bacteria and a culture medium. The contents of Thiobacillus denitrificans and sulfur bacteria in the culture medium are 5×10 10 CFU / ml and 1.5×10 10 CFU / ml;

[0065] The components and contents of the culture medium are as follows:

[0066] 2 g of ammonium chloride, 5 g of sodium sulfite, 2 g of potassium dihydrogen phosphate, 1 g of sodium chloride, 0.2 g of calcium sulfate, 1 L of water.

[0067] ②. Material B includes microporous aggregate, coating material and starch layer. The microporous aggregate is coated outside the coating material, and the starch layer is coated outside the microporous aggregate:

[0068] The microporous aggregate includes activated carbon, sponge iron, silicon sulfide and silicon carbide. The mass ratio of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregate is 0.8:1.5:2.7:1.8;

[0069] The coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder. The carbon source is glucose and the nitrogen source is nitrite. The mass ratio of the carbon source, nitrogen source, sulfur powder and iron powder in the coating material is 1:1.3:2.6:2.

[0070] The mass ratio of material A to material B is 3:90.

[0071] The composite packing catalyst of this example is tested by electron microscopy, as Figure 1 shown. Example 4

[0072] This example provides a denitrifying sulfur-iron composite packing catalyst, which is the same as Example 1, except that the coating material further contains trace elements, and the mass ratio of the trace elements is 3% of the whole coating material; the trace elements include Fe 2+ , Cu 2+ and Zn 2+ . Example 5

[0073] This embodiment provides a denitrifying sulfur-iron composite packing catalyst. It is the same as Embodiment 2, except that the coating material further contains trace elements, and the mass ratio of the trace elements is 5% of the entire coating material; the trace elements include Fe 2+ , Cu 2+ and Zn 2+ . Embodiment 6

[0074] This embodiment provides a denitrifying sulfur-iron composite packing catalyst. It is the same as Embodiment 3, except that the coating material further contains trace elements, and the mass ratio of the trace elements is 6% of the entire coating material; the trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

[0075] The preparation methods of the catalysts provided in the above Embodiments 1-6 include the following steps:

[0076] Weigh the coating material according to the ratio, then weigh the microporous aggregate, add an appropriate amount of water and mix, dissolve and stir, coat it on the outer layer of the coating material, and then prepare a starch film to coat on the outer layer of the microporous aggregate to obtain Material B;

[0077] Obtain Material A through biological cultivation;

[0078] Pack Material A and Material B separately and mix them during use.

[0079] For the catalysts prepared in the above Embodiments 1-6 used in sewage treatment, the obtained test data are as follows:

[0080]

[0081] In summary, the catalyst prepared by the present invention has a high denitrification efficiency and can be reused.

[0082] The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention.

[0083] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A denitrification ferrous sulfur composite filler catalyst, characterized in that: It comprises material A and material B, wherein the material A is a bacterial strain; the material B comprises microporous aggregate, coating material and starch layer; The microporous aggregate includes activated carbon, sponge iron, silicon sulfide and silicon carbide; The coating material comprises a carbon source, a nitrogen source, sulfur powder and iron powder; The mass ratio of material A to material B is (1-3): (50-90); The bacterial species include denitrifying thiobacillus, sulfur bacteria and culture medium, and the content of the denitrifying thiobacillus and sulfur bacteria in the culture medium is (1-5)×10 10 CFU / ml, (0.5~1.5)×10 10 CFU / ml; The components and contents of the culture medium are as follows: Ammonium chloride 1-2g, sodium sulfite 2-5g, potassium dihydrogen phosphate 1-2g, sodium chloride 0.5-1g, calcium sulfate 0.1-0.2g, water 1L; The carbon source in the coating material is glucose, and the nitrogen source is nitrite; The microporous aggregate is coated on the outside of the coating material, and the starch layer is coated on the outside of the microporous aggregate; The mass ratio of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregate is (0.2-0.8): (0.5-1.5): (1-2.7): (1.4-1.8); The mass ratio of the carbon source, nitrogen source, sulfur powder and iron powder in the coating material is: (0.4～1)：(0.6-1.3)：(1-2.6)：(1.2-2)。 2. A denitrification ferrous sulfur composite filler catalyst according to claim 1, characterized in that: The coating material further comprises trace elements, and the mass ratio of the trace elements is 3-6% of the entire coating material.

3. A denitrification ferrous sulfur composite filler catalyst according to claim 2, characterized in that: The trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

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