Sewage treatment biological agent and preparation method and application thereof

Abstract

The present invention provides a sewage treatment biological agent and a preparation method and application thereof. The sewage treatment biological agent according to an embodiment of the present invention includes an induced nucleus. The induced nucleus has good bioaffinity. A microbial flora can be attached to the induced nucleus to achieve rapid growth. As the microbial flora gathers and grows on the induced nucleus, the granulation is gradually achieved by the sewage treatment biological agent to facilitate the sewage treatment. The microbial flora grows on the induced nucleus, and the growth process of microbial flora is a covering growth process which starts from the induced nucleus and gradually expands outward and centers on the induced nucleus. During the growth of microbial flora, extracellular polymers are secreted, which can further promote the granulation process by the sewage treatment biological agent.

Claims

1. A sewage treatment biological agent, comprising: an induced nucleus and a microbial flora grown on the induced nucleus, the induced nucleus comprising nutrient components required for the growth of the microbial flora, wherein the sewage treatment biological agent is obtained by a process comprising the step of growing the microbial flora to induce a gradual reduction in the volume of the induced nucleus, wherein the induced nucleus has a three-dimensional helical structure, a density of the induced nucleus is greater than a density of sewage to be treated using the sewage treatment biological agent, wherein a preparation raw material of the induced nucleus comprising the following components in parts by weight: a degradable plastic, 95-85 parts; a catalyst, 1-5 parts; wherein the catalyst comprises amino acids, inorganic salts, or vitamins; a mineral powder, 2-5 parts; wherein the mineral powder comprises calcium powder and pyrite powder, a mass ratio of calcium powder to pyrite powder is 1:4, wherein the mineral powder serves as an electron donor to provide an alternative carbon source; and a foaming agent, 2-5 parts; wherein the blowing agents comprises sodium carbonate or azodicarbonamide.

2. The sewage treatment biological agent according to claim 1, wherein the three-dimensional helical structure has a length of 0.5-2.5 mm.

3. A preparation method for the sewage treatment biological agent according to claim 1, comprising: mixing the induced nucleus and an activated sludge to obtain a mixture; putting the mixture into a pulse up-flow reactor for membrane formation, hydraulic sieving and granulation to obtain the sewage treatment biological agent.

4. The preparation method according to claim 3, wherein a sewage in the pulse up-flow reactor enters the pulse up-flow reactor in a pulse manner after being oxygenated and aerated, wherein before being oxygenated and aerated the sewage has a COD of 100 mg/L-400 mg/L, an ammonia nitrogen of 15 mg/L-40 mg/L, and a total nitrogen of 15 mg/L-45 mg/L.

5. The preparation method according to claim 3, wherein the preparation method further comprises forming a flow shear force from the bottom to the top in the pulse up-flow reactor by pulse inflow of 5 s/time to 40 s/time.

6. The sewage treatment biological agent according to claim 1, wherein the preparation raw materials of the induced nucleus comprise: hydrophilic surface modifiers; polyols, quaternary ammonium salts and sulfonates.

7. The sewage treatment biological agent according to claim 1, wherein the three-dimensional helical structure has pores distributed thereon.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a process flow diagram for the preparation of a sewage treatment biological agent.

(2) FIG. 2 shows a visual observation result for an induced nucleus prepared in Example 1.

(3) FIG. 3 shows a microscopic observation result for the induced nucleus prepared in Example 1.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(4) Hereinafter, embodiments of the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

Example 1

(5) In this example, a sewage treatment biological agent is prepared, and the specific process is as follows.

(6) (1) Preparation of induced nucleus: the recovered degradable plastic is melt and blended and then pelletized and extruded to form a three-dimensional helical structure. The procedure is shown in FIG. 1. In FIG. 1, 1 is an induced nucleus with a three-dimensional helical structure, and 2 is an aggregate of microbial colonies attached to the induced nucleus for growth.

(7) The length of the induced nucleus of the three-dimensional helical structure is 1-2 mm. The resulting induced nucleus is prepared as shown in FIGS. 2 and 3. FIG. 2 shows a visual observation result, and FIG. 3 shows a microscopic observation result. As can be seen from FIGS. 2 and 3, the aggregate structure of the microbial flora attached to the induced nucleus for growth is compact.

(8) Among them, the degradable plastics are recycled degradable plastic bags and degradable mulching films.

(9) The preparation raw material of the induced nucleus is a degradable plastic.

(10) (2) Preparation of sewage treatment biological agent:

(11) The prepared induced nucleus is placed in the sewage for cultivation. The sewage enters the pulse up-flow reactor in a pulse manner after being oxygenated and aerated, wherein the sewage has a COD of 100 mg/L-400 mg/L, an ammonia nitrogen of 15 mg/L-40 mg/L, and a total nitrogen of 15 mg/L-45 mg/L.

(12) The determination of the culture endpoint can be judged according to the particle size and settling rate.

(13) One way to determine the culture endpoint is to consider the culture complete when the settling velocity of the sewage treatment biological agent is much higher than that of the floc sludge.

(14) After 50 days of culture, it is observed that the sewage treatment biological agent is observed to be 1.5-3 mm, granular, compact and excellent in settling performance.

Example 2

(15) In this example, a sewage treatment biological agent is prepared, and the specific process is as follows.

(16) (1) Preparation of induced nucleus: the recovered degradable plastic is melt and blended with a catalyst and then pelletized and extruded to form a three-dimensional helical structure.

(17) The length of the induced nucleus of the three-dimensional helical structure is 1-2 mm.

(18) The degradable plastics are degradable plastic bags and degradable mulching films, and the catalyst is phenylalanine.

(19) Preparation raw materials of the induced nucleus include the following components in parts by weight.

(20) a degradable plastics, 95 parts;

(21) a catalyst, 5 parts.

(22) (2) Preparation of sewage treatment biological agent:

(23) The prepared induced nucleus is placed in the same sewage and reactor as in Example 1 for cultivation.

(24) After 42 days of culture, it is observed that the sewage treatment biological agent is observed to be 1.5-3 mm, granular, compact and excellent in settling performance.

Example 3

(25) In this example, a sewage treatment biological agent is prepared, and the specific process is as follows.

(26) (1) Preparation of induced nucleus: the recovered degradable plastic, the catalyst and the mineral powder are melt and blended and then pelletized and extruded to form a three-dimensional helical structure.

(27) The length of the induced nucleus of the three-dimensional helical structure is 1-2 mm.

(28) The degradable plastics are degradable packaging bags and degradable mulching films. The catalyst is phenylalanine. The mineral powder is calcium powder and pyrite powder, with the mass ratio of calcium powder to pyrite powder being 1:4.

(29) Preparation raw materials of the induced nucleus include the following components in parts by weight.

(30) a degradable plastics, 92 parts;

(31) a catalyst, 5 parts;

(32) a mineral powder, 3 parts.

(33) (2) Preparation of sewage treatment biological agent:

(34) The prepared induced nucleus is placed in the same sewage and reactor as in Example 1 for cultivation.

(35) After 35 days of culture, it is observed that the sewage treatment biological agent is observed to be 1.5-3 mm, granular, compact and excellent in settling performance.

Example 4

(36) In this example, a sewage treatment biological agent is prepared, and the specific process is as follows.

(37) (1) Preparation of induced nucleus: the recovered degradable plastic is melt and blended with a catalyst, a mineral powder and a foaming agent, and then pelletized and extruded to form a three-dimensional helical structure.

(38) The length of the induced nucleus of the three-dimensional helical structure is 1-2 mm.

(39) The degradable plastics are degradable plastic bags and degradable mulching films. The catalysts are amino acid and inorganic salt. The mineral powder is calcium powder and pyrite. The foaming agent is sodium carbonate. The mass ratio of calcium powder to pyrite powder is 1:4.

(40) Preparation raw materials of the induced nucleus include the following components in parts by weight.

(41) a degradable plastics, 90 parts;

(42) a catalyst, 5 parts;

(43) a calcium powder, 3 parts;

(44) a foaming agent, 2 parts.

(45) (2) Preparation of sewage treatment biological agent:

(46) The prepared induced nucleus is placed in the same sewage and reactor as in Example 1 for cultivation.

(47) After 30 days of culture, it is observed that the sewage treatment biological agent is observed to be 1.5-3 mm, granular, compact and excellent in settling performance.

Comparative Example 1

(48) In this comparative example, a sewage treatment biological agent is prepared, which differs from Example 1 in that no degradable plastic is used and polyethylene is used in the raw material for the preparation of the induced nucleus.

Comparative Example 2

(49) In this comparative example, a sewage treatment biological agent is prepared, which differs from Example 1 in that no degradable plastic is used in the raw material for the preparation of the induced nucleus, and activated carbon particles are used.

Test Example

(50) The sewage treatment performance of the sewage treatment biological agents prepared in Examples 1 to 4 and Comparative Examples 1 and 2 is tested. After the sewage treatment biological agent is cultured completely, the water in and out of the system is sampled and tested. The detection indicators include water quality indicators such as COD, ammonia nitrogen and total nitrogen, and sludge indicators such as MLSS and SVI, which evaluate the capacity of the cultured sewage treatment biological agent to treat municipal sewage.

(51) Before treatment, in the sewage, COD is 100 mg/L-400 mg/L, ammonia nitrogen is 15 mg/L-40 mg/L, and total nitrogen is 15 mg/L-45 mg/L.

(52) After the sewage treatment biological agent is cultured completely, the water samples at the inlet and outlet are taken for testing continuously for 30 days. The data in Table 1 is the average value of the removal efficiency of each pollutant for continuous 30 days.

(53) The results of the treatment are shown in Table 1.

(54) TABLE-US-00001 TABLE 1 Ammonia COD nitrogen Total nitrogen removal rate removal rate removal rate Culture (%) (%) (%) period/d Example 1 93.5 96.9 78.5 50 Example 2 95 97 80.1 42 Example 3 96.8 98.5 84.3 35 Example 4 97.9 98.9 85.5 30 Comparative 92.3 96.5 68.4 60 Example 1 Comparative 93.5 95.4 65.1 65 Example 2

(55) According to the test results in Table 1, the induced nucleus prepared with degradable plastics can provide attachment points for microbial growth, accelerate the granulation process of sewage treatment biological agent, and enhance the removal of organic matter and nitrogen in the sewage by the sewage treatment biological agent. The culture period of sewage treatment biological agent with basic degradable plastics as induced nucleus is 50d, and the removal rates of COD, ammonia nitrogen and total nitrogen are 93.5%, 96.9% and 78.5%, respectively. According to Comparative Examples 1 and 2, the sewage treatment biological agent prepared by using polyethylene and activated carbon particles as an inert material to induced nucleus has a loose structure. The removal rate of pollutants in the sewage is much lower than that of the sewage treatment biological agent in the examples. In addition, there is a phenomenon that the sewage treatment biological agent disintegrates in the treatment process. By blending and granulating the degradable plastics with the catalyst, mineral powder and foaming agent by melting, the new induced nucleus can further shorten the culture period of sewage treatment biological agent. The prepared sewage treatment biological agent has compact structure and good settling performance. In addition, the addition of catalyst and mineral powder can effectively improve the removal efficiency of organic matter and nitrogen by the sewage treatment biological agent.

(56) Although the present invention has been described in detail with reference to the examples, the present invention is not limited to the above examples. Various changes may be made within the scope of knowledge of those skilled in the art without departing from the spirit of the present invention.