Denitrification sulfur-iron composite filler catalyst and preparation method thereof

Abstract

The invention is applicable to the technical field of sewage treatment, and provides a denitrifying sulfur-iron composite filler catalyst and a preparation method thereof, the denitrifying sulfur-iron composite filler catalyst comprises a material A and a material B. The material A is a strain; the material B comprises microporous aggregate, a coating material and a starch layer; the microporous aggregate comprises 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 the material A to the material B is (1-3): (50-90); preferably, the strain comprises thiobacillus denitrificans, sulfur bacteria and a culture medium, and the content of the thiobacillus denitrificans in the culture medium is (1-5) * 10 < 10 > CFU / ml, and the content of the sulfur bacteria in the culture medium is (0.5-1.5) * 10 < 10 > CFU / ml; the culture medium comprises the following components: 1-2g of ammonium chloride, 2-5g of sodium sulfite, 1-2g of monopotassium phosphate, 0.5-1g of sodium chloride, 0.1-0.2 g of calcium sulfate and 1L of water. The catalyst prepared by the invention is used for sewage treatment, has high denitrification efficiency and certain reusability, and is economical, environment-friendly and low in cost.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, in particular to a denitrification ferrous sulfide composite filler catalyst and a preparation method thereof. Background Art

[0002] Wastewater 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 discharge standards or be reused. The main goals of sewage treatment are to reduce pollution to the environment, protect water resources, and ensure public health.

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

[0004] Most of the existing biological treatment methods are nitrification denitrification, which requires a high dissolved oxygen concentration and a suitable temperature and pH value. Since it is an aerobic reaction, the nitrification process consumes a large amount of oxygen, which increases the treatment cost. In this regard, the present application proposes a denitrification sulfide-iron composite filler catalyst and a preparation method thereof. Summary of the invention

[0005] The purpose of the present invention is to provide a denitrification sulfide-iron composite filler catalyst and a preparation method thereof, so as to solve the problem that nitrification denitrification in the prior art requires a higher dissolved oxygen concentration and requires a suitable temperature and pH value. Since it is an aerobic reaction, the nitrification process consumes a large amount of oxygen, which increases the processing cost.

[0006] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a denitrification sulfide-iron composite filler catalyst, comprising material A and material B, wherein the material A is a strain; the material B comprises 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 comprises a carbon source, a nitrogen source, sulfur powder and iron powder; The mass ratio of the A material to the B material is (1-3): (50-90).

[0007] Preferably, the strains include denitrifying Thiobacillus, sulfur bacteria and culture medium, and the content of denitrifying Thiobacillus and sulfur bacteria in the culture medium is (1-5)×10 10 CFU / ml, (0.5~1.5)×1010 CFU / ml.

[0008] Preferably, 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.

[0009] Preferably, the carbon source in the coating material is glucose, and the nitrogen source is nitrite.

[0010] 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.

[0011] 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).

[0012] Preferably, 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).

[0013] Preferably, the coating material further comprises trace elements, and the mass ratio of the trace elements is 3-6% of the entire coating material.

[0014] Preferably, the trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

[0015] The second aspect of the present invention provides a method for preparing the catalyst according to the first aspect of the present invention, comprising the following steps: Weigh the coating material in proportion, then weigh the microporous aggregate, add appropriate amount of water, mix, dissolve and stir, and coat the coating material on the outer layer, then prepare a starch film and coat the outer layer of the microporous aggregate to obtain material B; Material A is obtained through biological cultivation; Package material A and material B separately and mix them when using.

[0016] The present invention has at least the following beneficial effects: The invention provides a denitrification sulfide-iron composite filler catalyst and a preparation method thereof. The prepared catalyst is used for sewage treatment, has high denitrification efficiency, is reusable to a certain extent, is economical, environmentally friendly and has low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an electron microscope image of the composite filler catalyst obtained in Example 3 of the present invention. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The invention provides a denitrification sulfide-iron composite filler catalyst, comprising material A and material B, wherein the material A is a bacterial strain; the material B comprises a microporous aggregate, a coating material and a starch layer; the microporous aggregate comprises activated carbon, sponge iron, silicon sulfide and silicon carbide; the coating material comprises a carbon source, a nitrogen source, sulfur powder and iron powder; and the mass ratio of the material A to the material B is (1-3): (50-90).

[0020] Furthermore, the strains include denitrifying Thiobacillus, sulfur bacteria and culture medium, and the content of denitrifying Thiobacillus and sulfur bacteria in the culture medium is (1-5)×10 10 CFU / ml, (0.5~1.5)×10 10 CFU / ml.

[0021] Further, 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.

[0022] Furthermore, the carbon source in the coating material is glucose, and the nitrogen source is nitrite.

[0023] Furthermore, 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.

[0024] Furthermore, the mass ratios of activated carbon, sponge iron, silicon sulfide and silicon carbide in the microporous aggregate are (0.2-0.8): (0.5-1.5): (1-2.7): (1.4-1.8).

[0025] Furthermore, 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).

[0026] Furthermore, the coating material also contains trace elements, the mass ratio of which is 3-6% of the entire coating material; the trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

[0027] The preparation method of the above catalyst comprises the following steps: Weigh the coating material in proportion, then weigh the microporous aggregate, add appropriate amount of water, mix, dissolve and stir, and coat the coating material on the outer layer, then prepare a starch film and coat the outer layer of the microporous aggregate to obtain material B; Material A is obtained through biological cultivation; Package material A and material B separately and mix them when using.

[0028] The activated carbon in the present invention can adsorb organic matter and impurities in sewage due to its high specific surface area and excellent adsorption capacity; the 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 provide a microporous structure, which is conducive to the attachment and growth of microorganisms; the glucose and nitrite in the coating material provide carbon source and nitrogen source for the microorganisms respectively, and the sulfur powder and iron powder participate in the sulfur cycle and the redox reaction of iron, and promote the denitrification process; the starch layer as the outer coating can protect the internal microporous aggregate and the coating material to prevent them from being damaged under the scouring of water flow, and provide an additional carbon source for the microorganisms to use.

[0029] The present invention can effectively reduce the demand for dissolved oxygen in the sewage treatment process, remove nitrogen through denitrification, reduce oxygen consumption, and thus reduce treatment costs. In addition, the bacterial strains in the catalyst can work effectively at lower temperatures and a wider pH range, improving the adaptability and flexibility of sewage treatment. At the same time, the combined design of microporous aggregates and coating materials enhances the overall stability and durability of the filler, so that the catalyst has a longer service life and higher treatment efficiency in the sewage treatment process, thereby improving the reuse rate. In summary, the present invention provides an efficient, economical, and environmentally friendly solution for the sewage treatment field.

[0030] Based on the above technical solution, the present invention provides the following partial embodiments: Example 1

[0031] This embodiment provides a denitrification sulfide-iron composite filler catalyst, including material A and material B.

[0032] ①, Material A is the strain: The strains include denitrifying Thiobacillus, sulfur bacteria and culture medium. The content of denitrifying Thiobacillus and sulfur bacteria in the culture medium is 1×10 10 CFU / ml, 0.5×10 10 CFU / ml; The components and contents of the culture medium are as follows: 1g ammonium chloride, 2g sodium sulfite, 1g potassium dihydrogen phosphate, 0.5g sodium chloride, 0.1 calcium sulfate, 1L water.

[0033] ② Material B includes microporous aggregate, coating material and starch layer. 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 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; The coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder, wherein the carbon source is glucose and the nitrogen source is nitrite; the mass ratio of the carbon source, the nitrogen source, the sulfur powder and the iron powder in the coating material is 0.4:0.6:1:1.2.

[0034] The mass ratio of material A to material B is 1:50. Example 2

[0035] This embodiment provides a denitrification sulfide-iron composite filler catalyst, including material A and material B.

[0036] ①, Material A is the strain: The strains included denitrifying Thiobacillus, sulfur bacteria and culture medium. The content of denitrifying Thiobacillus and sulfur bacteria in the culture medium was 3×10 10 CFU / ml, 1×10 10 CFU / ml; The components and contents of the culture medium are as follows: 1.5g ammonium chloride, 3g sodium sulfite, 1.5g potassium dihydrogen phosphate, 0.8g sodium chloride, 0.15g calcium sulfate, 1L water.

[0037] ② Material B includes microporous aggregate, coating material and starch layer. 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 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; The coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder, wherein the carbon source is glucose and the nitrogen source is nitrite; the mass ratio of the carbon source, the nitrogen source, the sulfur powder and the iron powder in the coating material is 0.7:1:1.8:1.4.

[0038] The mass ratio of material A to material B is 2:73. Example 3

[0039] This embodiment provides a denitrification sulfide-iron composite filler catalyst, including material A and material B.

[0040] ①, Material A is the strain: The strains include denitrifying Thiobacillus, sulfur bacteria and culture medium. The content of denitrifying Thiobacillus and sulfur bacteria in the culture medium is 5×10 10 CFU / ml, 1.5×10 10 CFU / ml; The components and contents of the culture medium are as follows: 2g ammonium chloride, 5g sodium sulfite, 2g potassium dihydrogen phosphate, 1g sodium chloride, 0.2g calcium sulfate, 1L water.

[0041] ② Material B includes microporous aggregate, coating material and starch layer. 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 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; The coating material includes a carbon source, a nitrogen source, sulfur powder and iron powder, wherein the carbon source is glucose and the nitrogen source is nitrite; the mass ratio of the carbon source, the nitrogen source, the sulfur powder and the iron powder in the coating material is 1:1.3:2.6:2.

[0042] The mass ratio of material A to material B is 3:90.

[0043] The composite filler catalyst of this embodiment was tested by electron microscope. Figure 1 shown. Example 4

[0044] This embodiment provides a denitrification sulfide-iron composite filler catalyst, which is the same as that of embodiment 1, except that the coating material further contains trace elements, and the mass ratio of the trace elements is 3% of the entire coating material; the trace elements include Fe 2+ , Cu 2+ and Zn 2+ . Example 5

[0045] This embodiment provides a denitrification sulfide-iron composite filler catalyst, which is the same as that of 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+ . Example 6

[0046] This embodiment provides a denitrification sulfide-iron composite filler catalyst, which is the same as that of 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+ .

[0047] The preparation method of the catalyst provided in the above embodiments 1-6 comprises the following steps: Weigh the coating material in proportion, then weigh the microporous aggregate, add appropriate amount of water, mix, dissolve and stir, and coat the coating material on the outer layer, then prepare a starch film and coat the outer layer of the microporous aggregate to obtain material B; Material A is obtained through biological cultivation; Package material A and material B separately and mix them when using.

[0048] The catalysts prepared in the above Examples 1-6 were used for sewage treatment, and the test data obtained were as follows:

[0049] In summary, the catalyst prepared by the present invention has high denitrification efficiency and can be reused.

[0050] The above shows and describes the basic principles, main features and advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0051] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that 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 the A material to the B material is (1-3): (50-90).

2. A denitrification ferrous sulfur composite filler catalyst according to claim 1, characterized in that: The bacterial species include denitrifying thiobacillus, sulfur bacteria and culture medium, and the content of denitrifying thiobacillus and sulfur bacteria in the culture medium is (1-5)×10 10 CFU / ml, (0.5~1.5)×10 10 CFU / ml.

3. A denitrification ferrous sulfur composite filler catalyst according to claim 2, characterized in that: 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.

4. A denitrification ferrous sulfur composite filler catalyst according to claim 3, characterized in that: The carbon source in the coating material is glucose, and the nitrogen source is nitrite.

5. A denitrification ferrous sulfur composite filler catalyst according to claim 4, characterized in that: 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.

6. A denitrification ferrous sulfur composite filler catalyst according to claim 5, characterized in that: 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).

7. A denitrification ferrous sulfur composite filler catalyst according to claim 6, characterized in that: 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）。 8. A denitrification ferrous sulfur composite filler catalyst according to claim 7, 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.

9. A denitrification ferrous sulfur composite filler catalyst according to claim 8, characterized in that: The trace elements include Fe 2+ , Cu 2+ and Zn 2+ .

10. A method for preparing the catalyst according to any one of claims 1 to 9, characterized in that: The following steps are involved: Weigh the coating material in proportion, then weigh the microporous aggregate, add appropriate amount of water, mix, dissolve and stir, and coat the coating material on the outer layer, then prepare a starch film and coat the outer layer of the microporous aggregate to obtain material B; Material A is obtained through biological cultivation; Package material A and material B separately and mix them when using.

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