Sewage deep phosphorus removal bacterial agent as well as preparation method and application thereof

Abstract

The invention relates to a sewage deep phosphorus removal microbial agent as well as a preparation method and application thereof, and provides a microcapsule type phosphorus removal microbial agent, which adopts filamentous sulfur bacteria Thiothrix, bacillus subtilis and achromobacter as core materials, and adopts gelatin, sodium alginate and calcium chloride as wall materials. Through cooperative use of the filamentous sulfur bacteria Thiothrix, the bacillus subtilis and the colorless thiobacillus, phosphorus and nitrogen in sewage can be deeply removed while the stability of the compound microbial agent in the use process is guaranteed, the total phosphorus removal rate is 96.5%, and the total nitrogen removal rate is 94.1%. The microcapsule is convenient to use and can be directly put into to-be-treated sewage to be slowly released, gelatin and sodium alginate are used as a composite wall material, so that the influence of O2 and oxidizing substances in water on florae in a microcapsule core material can be reduced, the utilization rate of the microbial inoculum is increased, the addition amount is reduced, and the production treatment cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and particularly to a bactericide for deep phosphorus removal from sewage and its preparation method and application. Background Art

[0002] With the acceleration of the urbanization process and industrial development, sewage treatment has become an important issue faced in urban environmental protection construction. The wastewater discharged during industrial production processes and urban residents' lives is the main source of sewage. Such sewage often contains a high concentration of phosphates, and the phosphorus content is significantly higher than that of natural water bodies, making it difficult to treat and posing a serious threat to the environment.

[0003] Excessive phosphorus in sewage can lead to eutrophication of water bodies, causing serious pollution of water bodies and further leading to ecological imbalance. Moreover, the phosphorus in sewage may also enter the land through irrigation or enter the human body through groundwater and other channels, having a negative impact on human health.

[0004] Currently, the commonly used sewage treatment methods include biological methods (such as A / O process, Phostrip process, oxidation ditch process) and chemical methods (such as calcium salt precipitation method, iron salt precipitation method, etc.). However, biological methods often require the construction of corresponding large-scale treatment equipment, resulting in relatively high treatment costs. Chemical methods require the addition of a large amount of chemical agents, increasing the treatment cost and the sludge generated after treatment also needs to be further treated harmlessly, otherwise it may cause secondary pollution to the environment.

[0005] As a special microbial bactericide, the phosphorus-removing bactericide can effectively remove phosphorus in sewage, and will not produce toxic and harmful substances during the phosphorus-removing process, having biodegradability and safety. The phosphorus-removing bactericide has a lower cost compared with the existing treatment methods, and can be adjusted according to the types and quantities of microorganisms in the strain to meet the complex and changeable sewage treatment requirements, which is one of the important development directions in the current sewage treatment field. Summary of the Invention

[0006] One of the purposes of the present invention is to provide a bactericide for deep phosphorus removal from sewage. By using Thiothrix, Bacillus subtilis, and Achromatium oxaliferum in synergy, while ensuring the stability of the composite microbial bactericide during use, it can deeply remove phosphorus and nitrogen in sewage.

[0007] To achieve the above purpose, the present invention provides the following technical solution: The phosphorus-removing bactericide is a microcapsule, including a core material and a wall material;

[0008] The core material contains the following components by mass: 100 - 200 parts of phosphorus-removing bacteria liquid; 30 - 50 parts of carrier;

[0009] The phosphorus-removing bacterial liquid contains the following components by mass: 20-60 parts of filamentous sulfur bacteria Thiothrix; 10-30 parts of Bacillus subtilis, and 20-60 parts of Achromatium;

[0010] The wall material includes gelatin, sodium alginate and calcium chloride.

[0011] The effective viable counts of filamentous sulfur bacteria Thiothrix, Bacillus subtilis and Achromatium in the phosphorus-removing bacterial liquid are 2.0×10 8 ~1.0×10 10 cfu / g.

[0012] The carrier is at least one of activated carbon and starch granules.

[0013] The core material contains the following components by mass: 200 parts of phosphorus-removing bacterial liquid; 50 parts of carrier.

[0014] The phosphorus-removing bacterial liquid contains the following components by mass: 50 parts of filamentous sulfur bacteria Thiothrix; 30 parts of Bacillus subtilis, and 50 parts of Achromatium.

[0015] The specific preparation steps are as follows:

[0016] S1: Disperse filamentous sulfur bacteria Thiothrix, Bacillus subtilis and Achromatium in deionized water to obtain a phosphorus-removing bacterial liquid. Add a carrier to the above phosphorus-removing bacterial liquid, and after stirring well, obtain solution A;

[0017] S2: Prepare solution B by mixing a 10% gelatin solution and 5% sodium alginate in a volume ratio of 1:1;

[0018] S3: Mix solutions A and B and then dropwise add them to a calcium chloride solution. After stirring for a period of time, filter, wash with deionized water, and dry to obtain the phosphorus-removing agent microcapsules.

[0019] The phosphorus-removing agent is used to treat phosphorus-containing sewage.

[0020] The beneficial effects brought by the technical solution provided by the present invention at least include:

[0021] 1. The present invention uses filamentous sulfur bacteria Thiothrix, Bacillus subtilis and colorless sulfur bacillus as composite bacterial agents. Colorless sulfur bacillus can remove nitrogenous compounds in sewage under aerobic conditions and convert sulfide into elemental sulfur. Filamentous sulfur bacteria Thiothrix is ​​a sulfur-mediated denitrifying phosphorus removal bacterium, which absorbs phosphate in sewage under aerobic conditions to synthesize polyphosphate for storage. At the same time, the elemental sulfur produced by colorless sulfur bacteria can also enhance the denitrification and phosphorus removal efficiency of filamentous sulfur bacteria Thiothrix, and the sulfate produced in the phosphorus removal process of filamentous sulfur bacteria Thiothrix can promote the aerobic denitrification process of colorless sulfur bacteria. The two cooperate to realize the self-circulation of sulfur elements and will not produce additional pollutants. Bacillus subtilis removes phosphates in sewage under aerobic conditions, and secretes a variety of organic acid compounds in the process, which reduces the pH of sewage and is conducive to the growth of filamentous sulfur bacteria Thiothrix and colorless sulfur bacillus. The three are used in a coordinated manner to ensure the stability of the composite microbial agent during use, while deeply removing phosphorus and nitrogen from sewage.

[0022] 2. Adjust different ratios of filamentous sulfur bacteria Thiothrix, Bacillus subtilis and Colorless Thiobacillus. When the ratio is 50:30:50, the phosphorus and nitrogen removal effect is best, with a total phosphorus removal rate of 96.5% and a total nitrogen removal rate of 94.1%.

[0023] 3. The microbial agent is processed into microcapsules for easy use and can be directly put into the sewage to be treated for slow release. Gelatin and sodium alginate as composite wall materials can reduce the bacterial flora in the microcapsule core material from being affected by O in water. 2 As well as the influence of oxidizing substances, the utilization rate of bacterial agents is improved, the amount added is reduced, and the production and processing costs are reduced. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below.

[0025] Embodiment 1:

[0026] S1: Dispersing filamentous sulfur bacteria Thiothrix, Bacillus subtilis and colorless sulfur bacillus in deionized water to obtain a phosphorus removal bacterial solution, adding a carrier to the phosphorus removal bacterial solution, and stirring sufficiently to obtain a solution A;

[0027] S2: Prepare solution B by mixing 10% gelatin solution and 5% sodium alginate solution in a volume ratio of 1:1;

[0028] S3: Mix solutions A and B and add them dropwise into a 1% calcium chloride solution, stir for a period of time, filter, wash with deionized water, and dry to obtain phosphorus removal bacteria microcapsules.

[0029] Examples 2 and 3:

[0030] The dosages of each component and the preparation steps in this example are basically the same as those in Example 1, except that the dosages of each component are different. The specific dosages are shown in Table 1.

[0031] Comparative Example

[0032] The dosages of each component and the preparation steps in Comparative Examples 1 and 2 are basically the same as those in Example 1, except that the dosages of each component are different. The specific dosages are shown in Table 1.

[0033] Table 1 Dosages of components of different samples

[0034]

[0035] Performance evaluation

[0036] Add the above-mentioned bacterial agents of the examples and comparative examples to the papermaking wastewater, and add 20 g of the bacterial agent to each liter of wood pulp papermaking wastewater, and calculate the removal rates of NH 3 -N and TP. Among them, the content of NH 3 -N is determined by the spectrophotometric method with Nessler's reagent (refer to HJ535-2009); the content of TP is determined by the molybdenum antimony anti-spectrophotometric method (refer to GB / T11893-89). The removal rate = (1 - (the content of NH 3 -N / TP after treatment / the initial content of NH 3 -N / TP)) * 100%.

[0037] Table 2 NH 3 -N / TP removal rate

[0038]

[0039] As can be seen from Table 2, the bacterial agent of Example 1 of the present application can play a long-term effect (30 d) during the sewage treatment process, and has a high removal effect on the total nitrogen and total phosphorus in the sewage. The NH 3 -N / TP removal rates

[0040] are 94.1% and 96.5% respectively.

[0041] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sewage deep phosphorus removal bacterial agent, characterized in that: The phosphorus removal bacteria agent is a microcapsule, comprising a core material and a wall material; The core material comprises the following components by weight: 100-200 parts of phosphorus removal bacteria solution; 30-50 parts of carrier; The phosphorus removal bacteria solution comprises the following components by weight: 20-60 parts of filamentous sulfur bacteria Thiothrix; 10-30 parts of Bacillus subtilis, and 20-60 parts of colorless sulfur bacillus; The wall material comprises gelatin, sodium alginate and calcium chloride.

2. The phosphorus removal bacterial agent according to claim 1, characterized in that The effective live bacteria count of filamentous sulfur bacteria Thiothrix, Bacillus subtilis and colorless sulfur bacillus in the dephosphorization bacterial solution is 2.0×10 8 ~1.0×10 10 cfu / g.

3. The phosphorus removal bacterial agent according to claim 1, characterized in that: The carrier is at least one of activated carbon and starch particles.

4. The phosphorus removal bacterial agent according to claim 1, characterized in that: The core material comprises the following components by mass: 200 parts of phosphorus removal bacteria solution and 50 parts of carrier.

5. The phosphorus removal bacterial agent according to claim 1, characterized in that: The phosphorus removal bacterial solution comprises the following components by mass: 50 parts of filamentous sulfur bacteria Thiothrix; 30 parts of Bacillus subtilis and 50 parts of colorless sulfur bacillus.

6. The method for preparing the sewage deep phosphorus removal bacterial agent according to any one of claims 1 to 5, characterized in that: The specific steps are: S1: Dispersing filamentous sulfur bacteria Thiothrix, Bacillus subtilis and colorless sulfur bacillus in deionized water to obtain a phosphorus removal bacterial solution, adding a carrier to the phosphorus removal bacterial solution, and stirring sufficiently to obtain a solution A; S2: Prepare solution B by mixing 10% gelatin solution and 5% sodium alginate solution in a volume ratio of 1:1; S3: Mix solutions A and B and add them dropwise into the calcium chloride solution. Stir for a period of time and then filter. Wash with deionized water and dry to obtain phosphorus removal bacteria microcapsules.

7. The use of the sewage deep phosphorus removal bacterial agent according to any one of claims 1 to 6, characterized in that: Used to treat phosphorus-containing wastewater.

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