A bacterial-algal symbiotic treatment agent for aquaculture wastewater, and its preparation method and application

Abstract

The present application relates to the field of wastewater treatment technology, and specifically to a bacterial algae symbiotic treatment agent for aquaculture wastewater, and its preparation method and application. The bacterial algae symbiotic treatment agent of the present application comprises the following components per liter: 100-150g of adsorption carrier, 20-50mg of microalgae, 50-80mL of bacterial seed liquid, and distilled water to 1L; the bacterial seed liquid is taken from aquaculture wastewater, and the concentration of the bacterial species in the bacterial seed liquid is 10 7 ‑10 9 CFU / mL. The bacteria-algae symbiotic treatment agent uses microalgae and bacteria taken from aquaculture wastewater to form a relatively stable bacteria-algae symbiotic system, which can be directly added to aquaculture wastewater for wastewater treatment, and can effectively remove COD, total nitrogen and total phosphorus in aquaculture wastewater, realizing the recycling of resources, and has good convenience of use and water purification effect.

Description

Technical Field

[0001] The present application relates to the technical field of wastewater treatment, and in particular to a bacteria-algae symbiotic treatment agent for aquaculture wastewater, and a preparation method and application thereof. Background Art

[0002] Animal husbandry and poultry farming is a pillar industry of the rural economy and is extremely important in ensuring people's food security and increasing farmers' income.

[0003] As the primary producer in the trophic level of the food chain, microalgae maintains its growth and proliferation process by absorbing a large amount of nitrogen and phosphorus, and fixes carbon dioxide through photosynthesis to achieve carbon dioxide emission reduction. Therefore, its own growth and proliferation process is the process of removing nitrogen and phosphorus from water, achieving the effect of reducing the nitrogen and phosphorus content in water. At the same time, microalgae are collected through bioflocculants, and the recovered microalgae can be refined into biodiesel, which not only significantly improves the efficiency of resource utilization of livestock and poultry wastewater, but also provides more solutions to solve the problem of national energy shortage. Therefore, the use of microalgae to achieve resource treatment of aquaculture wastewater has good prospects.

[0004] The microalgae culture system is not just about the microalgae working. The microorganisms in the system play an important role in the decomposition of organic matter. The algae-bacteria symbiotic system can not only perform photosynthetic oxygenation, reduce the aeration cost of wastewater treatment, but also reduce greenhouse gas emissions during wastewater treatment. In recent years, many scholars have conducted in-depth explorations on the photosynthetic oxygenation function of the algae-bacteria symbiotic system, wastewater nitrogen and phosphorus removal, and organic matter biodegradation.

[0005] However, when using the bacteria-algae symbiotic system to treat aquaculture wastewater, people need to first inoculate microalgae into the aquaculture wastewater and cultivate it to the logarithmic growth period, and then add a set amount of purification bacteria. The bacteria-algae symbiotic system constructed in this way has limited treatment effect on aquaculture wastewater, and the operation steps are cumbersome, resulting in low treatment efficiency of aquaculture wastewater. Summary of the invention

[0006] In order to simplify the treatment steps of aquaculture wastewater, the present application provides a bacteria-algae symbiotic treatment agent for aquaculture wastewater, and a preparation method and application thereof. The bacteria-algae symbiotic treatment agent utilizes microalgae and bacteria taken from aquaculture wastewater to form a relatively stable bacteria-algae symbiotic system, which can be directly put into aquaculture wastewater for wastewater treatment, and can effectively remove COD, total nitrogen and total phosphorus in aquaculture wastewater, thereby realizing the recycling of resources, and has good convenience of use and water purification effect.

[0007] In the first aspect, the present application provides a bacterial-algae symbiotic treatment agent for aquaculture wastewater, wherein each liter of the bacterial-algae symbiotic treatment agent comprises the following components: 100-150 g of an adsorption carrier, 20-50 mg of microalgae, and 50-80 mL of a bacterial seed solution, which is fixed to 1 L with distilled water; the bacterial seed solution is taken from aquaculture wastewater, and the concentration of the bacterial species in the bacterial seed solution is 10 7 -10 9 CFU / mL.

[0008] In the present application, the microalgae and bacterial liquid are combined with an adsorption carrier according to the above-mentioned ratio, and the bacterial strains are fermented by using the oxygen produced by the photosynthesis of the microalgae, so as to form a relatively stable bacterial-algal symbiotic system, which can be directly put into aquaculture wastewater for wastewater treatment. The bacterial strains do not need to be added after the microalgae are cultured to the logarithmic growth phase. On this basis, the selection of bacteria taken from aquaculture wastewater can avoid the stage of bacterial adaptation to the environment, thereby enabling the microalgae and bacterial strains to play a better role, effectively removing COD, total nitrogen and total phosphorus in aquaculture wastewater, realizing the recycling of resources, and having good convenience of use and water purification effect.

[0009] Preferably, the microalgae is a mixture of Chlorella, Botrytis cinerea and Scenedesmus.

[0010] Preferably, the weight ratio of Chlorella, Botrytis cinerea and Scenedesmus is 2:1:2.

[0011] By adopting the above technical scheme, Chlorella can be both autotrophic and heterotrophic, and it has a relatively high absorption capacity for nitrogen and phosphorus in the water body, but its photosynthesis is easily affected by the culture ventilation volume; Grape algae is a self-operating micro-plankton algae, which grows rapidly and can increase the intervals between Chlorella, providing sufficient circulation channels for dissolved oxygen; Scenedesmus reproduces rapidly and has strong adaptability, and its intracellular chlorophyll content is high, so it can produce a large amount of oxygen to accelerate the gas circulation efficiency in aquaculture wastewater. As a result, the three kinds of microalgae complement each other, so that a high content of live microalgae and live bacterial species is maintained in the system, which can effectively play a role in water purification. Among them, when the weight ratio of Chlorella, Grape algae and Scenedesmus is 2:1:2, the bacterial algae symbiotic treatment agent prepared therefrom has a higher content growth rate of microalgae and bacterial species, and the removal rate of COD, total nitrogen and total phosphorus in aquaculture wastewater is significantly higher than other weight ratios, so it is further preferred.

[0012] Preferably, the adsorption carrier is a mixture of sugarcane waste powder and puffed corn flour.

[0013] Preferably, the weight ratio of the sugarcane waste powder to the puffed corn flour is 9:1.

[0014] By adopting the above technical solution, since the structure of the bacterial strain is often smaller than that of microalgae, it is easy to stratify with the microalgae when mixed with the microalgae. In this regard, the present application uses sugarcane waste powder to provide support for the bacterial strain, and the bacterial strain adheres to the surface of the sugarcane waste powder to form a bacterial strain group. Compared with freeing the bacterial strain in the treatment agent, the bacterial strain group can reduce the competition between the bacterial strain and the microalgae, and the bacterial strain in the bacterial strain group can effectively absorb the nutrients in the sugarcane waste powder for reproduction; in this technology, the present application uses puffed corn flour to increase the viscosity of the bacterial algae symbiotic system, thereby effectively increasing the stability of each component in the bacterial algae symbiotic treatment agent. Compared with other thickeners, the puffed corn flour used in the present application can also provide nutrients for microalgae and bacterial strains, which helps the microalgae and bacterial strains to have a certain effective activity in the bacterial algae symbiotic system formed by them, so as to facilitate their storage and transportation.

[0015] In a second aspect, the present application provides a method for preparing a bacteria-algae symbiotic treatment agent, comprising the following steps:

[0016] Take an appropriate amount of distilled water, add 100-150g of the adsorption carrier, stir until evenly dispersed, add 20-50mg of microalgae and 50-80mL of bacterial culture solution, and dilute to 1L with distilled water while stirring. Let it stand at room temperature for 15-30min, and then store it at 0-4℃ for later use.

[0017] The bacteria-algae symbiotic treatment agent of the present application is left to stand at room temperature after being fixed to volume, so that the bacteria can be stably attached to the sugarcane waste residue powder, and the microalgae provide oxygen for the reproduction of the bacteria. The bacteria-algae symbiotic treatment agent thus prepared has better system stability.

[0018] In a third aspect, the present application provides a method for treating aquaculture wastewater, using the aforementioned bacteria-algae symbiotic treatment agent.

[0019] Preferably, the method for treating aquaculture wastewater comprises the following steps:

[0020] The aquaculture wastewater is treated by aeration to make the ammonia nitrogen concentration in the aquaculture wastewater ≤100 mg / L, and the treated liquid is obtained after filtration; a bacteria-algae symbiotic treatment agent is added to the treated liquid, and the culture liquid is harvested after light cultivation.

[0021] By adopting the above technical solution, since the ammonia nitrogen concentration of aquaculture wastewater will affect the growth of microalgae to a certain extent, the present application limits its ammonia nitrogen concentration to conditions suitable for the growth of microalgae, which helps the bacteria-algae symbiotic treatment agent of the present application to better function.

[0022] Preferably, the amount of the bacteria-algae symbiotic treatment agent added is 5-15% of the volume of the treatment liquid.

[0023] By adopting the above technical solution, the content of microalgae and bacteria will affect the treatment effect of the bacteria-algae symbiotic treatment agent to a certain extent. Therefore, the addition amount of the bacteria-algae symbiotic treatment agent should not be too high or too low, and 5-15% is appropriate.

[0024] Preferably, the light culture is carried out in a closed environment.

[0025] By adopting the above technical solution, the closed environment helps microalgae and bacteria to quickly form a bacteria-algae symbiotic system in the aquaculture wastewater for wastewater treatment. At the same time, it can also prevent the discharge of gases such as carbon dioxide produced in the bacteria-algae cultivation process, thereby improving resource utilization.

[0026] In summary, this application has the following beneficial effects:

[0027] 1. The bacteria-algae symbiotic treatment agent of the present application utilizes microalgae and bacteria taken from aquaculture wastewater to formulate a relatively stable bacteria-algae symbiotic system, which can be directly put into aquaculture wastewater for wastewater treatment, and can effectively remove COD, total nitrogen and total phosphorus in aquaculture wastewater, thus realizing the recycling of resources, and has good convenience of use and water purification effect;

[0028] 2. The microalgae in the present application is preferably a mixture of Chlorella, Botrytis cinerea and Scenedesmus. The three microalgae complement each other and can effectively remove COD, total nitrogen and total phosphorus in aquaculture wastewater, and have a more excellent water purification effect;

[0029] 3. The adsorption carrier in the present application is preferably a mixture of sugarcane waste powder and puffed corn powder, which can effectively increase the stability of each component in the bacteria-algae symbiotic treatment agent and facilitate storage and transportation;

[0030] 4. The bacteria-algae symbiotic treatment agent of the present application is placed at room temperature for static treatment during preparation, so that the bacteria can be stably attached to the sugarcane waste residue powder, and the microalgae therein provide oxygen for the reproduction of the bacteria. The bacteria-algae symbiotic treatment agent thus prepared has better system stability. DETAILED DESCRIPTION

[0031] Source of raw materials

[0032] 1. Source of algae

[0033] Chlorella vulgaris comes from the freshwater algae species bank of the Institute of Hydrobiology, Chinese Academy of Sciences, with the number: FACHB1068; Botryococcus braunii comes from the freshwater algae species bank of the Institute of Hydrobiology, Chinese Academy of Sciences, with the number: FACHB 765; Desmodesmus sp.CHXl was separated from pig wastewater by the research team. The separation method is an existing technology and is not the main technology protected by this application, so it will not be further elaborated.

[0034] 2. Aquaculture wastewater

[0035] The aquaculture wastewater in this application is explained by taking pig farm wastewater as an example, and the pig farm wastewater comes from a stabilization pond of an ecological farm in Hangzhou, Zhejiang Province. In addition, the aquaculture wastewater can also be chicken farm wastewater, duck farm wastewater, etc. In the bacteria-algae symbiotic treatment agent corresponding to different aquaculture objects, the bacterial strain liquid used is changed accordingly.

[0036] In the bacterial algae symbiotic treatment agent corresponding to aquaculture wastewater in this application, the bacterial strain liquid used is taken from pig wastewater. The specific operation method is: take pig wastewater and use gauze to remove large particles in the pig wastewater, then use a 0.45μm filter membrane to remove excess water to concentrate the wastewater, so that the bacterial strain concentration in the wastewater is 10 7 -10 9 CFU / mL.

[0037] The present application is further described in detail below in conjunction with embodiments, comparative examples and application examples.

[0038] Example

[0039] Example 1

[0040] A bacteria-algae symbiotic treatment agent for aquaculture wastewater, the preparation method of which comprises the following steps:

[0041] Take an appropriate amount of distilled water, add 120g of the adsorption carrier, stir until evenly dispersed, add 30mg of microalgae and 60mL of bacterial culture solution (allowed to fluctuate within the range of 50-80mL), and dilute to 1L with distilled water while stirring. First, stand at room temperature (25°C) for 20min (allowed to fluctuate within the range of 15-30min), and then store at a temperature of 0-4°C for standby use;

[0042] The adsorption carrier was mixed with 108 g sugarcane waste powder (passed through a 60-mesh sieve) and 12 g puffed corn flour; the microalgae was mixed with 12 mg Chlorella, 6 mg Botrytis cinerea, and 12 mg Scenedesmus; the concentration of the strain in the strain solution was 2.1 × 10 8 CFU / mL.

[0043] Embodiment 2-10

[0044] In Examples 2-10, based on the method of Example 1, the dosage of the components is adjusted. For specific adjustments, please refer to Table 1 below.

[0045] Table 1 Composition list of Examples 1-10

[0046] Example 1 Example 2 Example 3 Example 4 Sugarcane waste powder / g 108 90 117 135 Puffed corn flour / g 12 10 13 15 Chlorella / mg 12 8 16 20 Botrytis cinerea / mg 6 4 8 10 Scenedesmus / mg 12 8 16 20 Bacterial liquid / mL 60 50 60 80

[0047] Comparative Example

[0048] Comparative Example 1

[0049] This comparative example is based on Example 1, but no adsorption carrier is added, that is, no sugarcane waste powder and puffed corn flour are added.

[0050] Comparative Example 2

[0051] In this comparative example, based on Example 1, no static treatment was performed when preparing the bacteria-algae symbiotic treatment agent.

[0052] Stability test

[0053] The bacteria-algae symbiotic treatment agents prepared in Examples 1-4 and Comparative Examples 1-2 were placed as samples in an environment with a temperature of 25°C and a light intensity of 6000 lux, and the samples were observed to see whether precipitation occurred on the 1st, 3rd, 5th, and 7th days. The test results are shown in Table 2 below, where the later the precipitation occurs, the more stable the components of the bacteria-algae symbiotic treatment agent are, and the more convenient it is to store and transport.

[0054] Table 2 Stability results of Examples 1-4 and Comparative Examples 1-2

[0055]

[0056] Combined with Table 2, the time when the bacteria-algae symbiotic treatment agents of Examples 1-4 precipitate is later than that of Comparative Example 1. It can be seen that the bacteria-algae symbiotic treatment agent of the present application uses an adsorption carrier to formulate microalgae and bacteria taken from aquaculture wastewater into a relatively stable bacteria-algae symbiotic system, which has good component stability and can be directly put into aquaculture wastewater for wastewater treatment, thereby realizing the recycling of resources and improving the convenience of using the bacteria-algae symbiotic system.

[0057] Among them, the stability of Comparative Example 2 is not as good as that of Example 1. This may be due to the operating steps of standing treatment at room temperature, which facilitates the stable attachment of the bacteria to the sugarcane waste residue powder, and the microalgae can provide oxygen for the reproduction of the bacteria. The bacteria-algae symbiotic treatment agent prepared in this way has better system stability, and can be stored and transported for a longer time.

[0058] Effective activity test

[0059] The bacteria-algae symbiotic treatment agents prepared in Examples 1-4 and Comparative Examples 1-2 were used as samples, and the samples were stored in an environment with a temperature of 4°C and no light (darkness). The contents of live microalgae and live bacterial strains on the 1st and 7th days of storage were respectively measured, wherein the contents of microalgae and bacterial strains were measured and recorded using a counting plate, and the content change rates of microalgae and bacterial strains were calculated (change rate % = (content on the 7th day - content on the 1st day) / content on the 1st day × 100%). The test results are shown in Table 3 below, wherein "+" indicates an increase in content, and "-" indicates a decrease in content.

[0060] Table 3 Effective activity results of Examples 1-4 and Comparative Examples 1-2

[0061] Change rate of microalgae content / % Bacteria content change rate / % Example 1 +10.6 +6.2 Example 2 +8.9 +4.6 Example 3 +9.3 +5.0 Example 4 +4.7 +1.1 Comparative Example 1 -5.5 -11.3 Comparative Example 2 +7.6 +3.2

[0062] Combined with Table 3, the change rates of the content of microalgae and bacterial strains in Examples 1-4 are all "+", and the content of live microalgae and live bacterial strains in Example 1 increases the most. Relatively speaking, the content of live microalgae and live bacterial strains in Comparative Example 1 is reduced due to the lack of the addition of an adsorption carrier, and the content of live microalgae and live bacterial strains in Comparative Example 2 that has not been statically treated is also less than that in Example 1. It can be seen that the adsorption carrier of the present application can ensure the effective activity of the microalgae and bacterial strains, and the bacteria-algae symbiotic treatment agent obtained thereby is relatively stable, which can ensure that the treatment agent has a good treatment effect. In addition, when preparing the bacteria-algae symbiotic treatment agent, the use of static treatment helps to make the system of microalgae and bacterial strains more stable, thereby obtaining a higher content of live microalgae and live bacterial strains.

[0063] Water purification effect test

[0064] The bacteria-algae symbiotic treatment agents prepared in Examples 1-4 and Comparative Examples 1-2 were used as samples to treat piggery wastewater. The treatment method included the following steps:

[0065] The pig farm wastewater was treated with aeration, and the aeration volume was set to 1.0 L / min, so that the ammonia nitrogen concentration in the pig farm wastewater was ≤100 mg / L. In this embodiment, the ammonia nitrogen concentration of the pig farm wastewater after aeration treatment was 96 mg / L, and the treated liquid was obtained after filtration through an 80-mesh sieve; the treated liquid was placed in a closed culture container, and the bacteria-algae symbiotic treatment agent was added to the treated liquid, and the amount of the bacteria-algae symbiotic treatment agent added was 10% of the volume of the treated liquid. Light culture was carried out, the culture temperature was 25°C, the light intensity was 8000 lux, and the total culture time was 5 days to harvest the culture liquid.

[0066] The culture solution was taken to determine the removal rates of COD, total nitrogen and total phosphorus. The results are shown in Table 4 below.

[0067] Table 4 Water purification effects of Examples 1-4 and Comparative Examples 1-2

[0068] COD removal rate / % Total nitrogen removal rate / % Total phosphorus removal rate / % Example 1 100.0 94.3 82.5 Example 2 97.7 90.2 79.3 Example 3 99.1 93.0 81.2 Example 4 98.5 91.8 80.5 Comparative Example 1 87.2 72.0 62.0 Comparative Example 2 92.0 85.5 75.3

[0069] Combined with Table 4, Examples 1-4 all have high removal rates of COD, total nitrogen and total phosphorus, while the removal rates of Comparative Examples 1 and 2 are relatively low. This may be because the microalgae and bacteria in the comparative examples failed to form a stable system, which made it difficult for the microalgae and / or bacteria to effectively reproduce in aquaculture wastewater for wastewater treatment.

[0070] In summary, the bacteria-algae symbiotic treatment agent of the present application has good component stability, can be directly put into aquaculture wastewater for wastewater treatment, can effectively remove COD, total nitrogen and total phosphorus in aquaculture wastewater, and has good convenience of use and water purification effect. Among Examples 1-4, the component stability and water purification effect of Example 1 are more excellent, so this application uses Example 1 as a preferred embodiment.

[0071] Embodiment 5-8

[0072] In Examples 5-8, based on the method of Example 1, the components and dosage of the adsorption carrier are adjusted. The specific adjustments are shown in Table 5 below.

[0073] Table 5 Ingredients of the adsorption carriers of Examples 1, 5-8 (in g)

[0074] Example 1 Example 5 Example 6 Example 7 Example 8 Sugarcane waste powder 108 90 115 / / Wheat straw powder / / / 108 108 Puffed corn flour 12 30 5 12 / Sodium Carboxymethyl Cellulose / / / / 12

[0075] Performance test

[0076] The bacteria-algae symbiotic treatment agents prepared in Examples 5-8 were used as samples to conduct the above stability test, effective activity test and water purification effect test. The test results are shown in Table 6 below.

[0077] Table 6 Test results of Examples 1, 5-8

[0078]

[0079] Combined with Table 6, the components of Examples 5, 7 and 8 are relatively stable, but the content change rate of microalgae and bacterial strains and the removal rate of COD, total nitrogen and total phosphorus are not as good as those of Example 1, and the performance of Example 6 is not as good as that of Example 1. It can be seen that when the adsorption carrier of the present application is configured with sugarcane waste powder and puffed corn powder at a weight ratio of 9:1, its water purification effect on aquaculture wastewater is more excellent. This may be because if the amount of puffed corn is too much, it will increase the viscosity of the system and affect the growth of microalgae and bacterial strains. If the amount of puffed corn is too little, it is difficult to form a stable system.

[0080] In addition, a combination of sugarcane waste powder and puffed corn is preferentially selected. This may be the bacteria-algae symbiotic treatment agent of the present application. The sugarcane waste powder can not only provide support for the bacteria to form a bacteria cluster, but also provide more nutrients for the microalgae and bacteria to grow and reproduce. Among them, the sugarcane waste powder has a greater effect on the growth and reproduction of bacteria. Puffed corn powder can also provide nutrients for the growth and reproduction of microalgae and bacteria. The bacteria-algae symbiotic treatment agent obtained thereby maintains a high activity and can quickly take effect when put into aquaculture wastewater.

[0081] Examples 9-14

[0082] Examples 9-14 Based on the method of Example 1, the components and amounts of microalgae were adjusted. The specific adjustments are shown in Table 7 below.

[0083] Table 7 Ingredients of the adsorption carriers of Examples 1, 9-14 (in g)

[0084]

[0085] Performance test

[0086] The bacteria-algae symbiotic treatment agents prepared in Examples 9-14 were used as samples to carry out the above stability test, effective activity test and water purification effect test. In the stability test, no precipitation occurred in the bacteria-algae symbiotic treatment agents of Examples 9-14. The water purification effect is shown in Table 8 below.

[0087] Table 8 Water purification results of Examples 1, 9-14

[0088]

[0089] Combined with Table 8, the content growth rate of microalgae and bacterial species and the COD, total nitrogen and total phosphorus removal rates of Example 1 are significantly higher than those of Examples 9-14. It can be seen that the microalgae in the present application is preferably a mixture of Chlorella, Botrytis cinerea and Scenedesmus. When the three kinds of microalgae are supplemented and configured in a weight ratio of 2:1:2, COD, total nitrogen and total phosphorus in aquaculture wastewater can be effectively removed, and a more excellent water purification effect can be achieved.

[0090] Application Examples

[0091] The application example of the present application preferably uses the bacteria-algae symbiotic treatment agent of Example 1 to treat pig farm wastewater, and the treatment method thereof refers to the above-mentioned water purification effect test.

[0092] Application Examples 1-4

[0093] Based on the method of the water purification effect test of Example 1, the addition amount of the algae symbiotic treatment agent was adjusted in Application Examples 1-4. Among them, the addition amount of Application Example 1 was 5%; the addition amount of Application Example 2 was 10% (i.e., the water purification effect test of Example 1); the addition amount of Application Example 3 was 15%; and the addition amount of Application Example 4 was 20%. See Table 9 below for the water purification effect.

[0094] Table 9 Water purification results of application examples 1-3

[0095] COD removal rate / % Total nitrogen removal rate / % Total phosphorus removal rate / % Application Example 1 92.5 88.2 75.8 Application Example 2 100.0 94.3 82.5 Application Example 3 100.0 95.7 84.3 Application Example 4 100.0 95.8 84.5

[0096] Combined with Table 9, Application Example 1 has a relatively low removal rate of COD, total nitrogen and total phosphorus in aquaculture wastewater due to the small amount of addition. As the amount of addition increases, the COD, total nitrogen and total phosphorus removal rates of the bacteria-algae symbiotic treatment agent first increase and then tend to be stable. In order to reduce the cost of use, this application prefers an addition amount of 5-15%, and further prefers an addition amount of 10% (Application Example 3).

[0097] Application Example 5

[0098] Based on Application Example 3, this application example adjusts the closed environment culture to open environment culture. In the harvested culture fluid, the COD removal rate is 99.5%, the total nitrogen removal rate is 93.6%, and the total phosphorus removal rate is 81.7%. It can be seen that the water purification effect of this application example is slightly lower than that of Application Example 3. It can be seen that the closed environment helps microalgae and bacteria to quickly form a bacterial algae symbiotic system in aquaculture wastewater for wastewater treatment. In addition, the sealed environment of Application Example 3 can also prevent the discharge of gases such as carbon dioxide produced during the bacterial algae culture process, thereby improving the utilization rate of resources.

[0099] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A bacterial-algal symbiotic treatment agent for aquaculture wastewater, characterized in that: Each liter of the bacterial-algae symbiotic treatment agent includes the following components: 100-150 g of adsorption carrier, 20-50 mg of microalgae, 50-80 mL of bacterial liquid, and the volume is fixed to 1 L with distilled water; the bacterial liquid is taken from aquaculture wastewater, and the concentration of the bacterial species in the bacterial liquid is 10 7 -10 9 CFU / mL; The microalgae is a mixture of Chlorella, Botrytis cinerea and Scenedesmus; the weight ratio of the Chlorella, Botrytis cinerea and Scenedesmus is 2:1:2; the adsorption carrier is a mixture of sugarcane waste powder and puffed corn flour, and the weight ratio of the sugarcane waste powder to the puffed corn flour is 9:

1.

2. The method for preparing the bacteria-algae symbiotic treatment agent according to claim 1, characterized in that: The following steps are involved: Take an appropriate amount of distilled water, add 100-150g of the adsorption carrier, stir until evenly dispersed, add 20-50mg of microalgae and 50-80mL of bacterial culture solution, and dilute to 1L with distilled water while stirring. Let it stand at room temperature for 15-30min, and then store it at 0-4℃ for later use.

3. A method for treating aquaculture wastewater, characterized in that: Use the bacteria-algae symbiotic treatment agent as claimed in claim 1.

4. The processing method according to claim 3, characterized in that: The following steps are involved: The aquaculture wastewater is treated by aeration to make the ammonia nitrogen concentration in the aquaculture wastewater ≤100 mg / L, and the treated liquid is obtained after filtration; a bacteria-algae symbiotic treatment agent is added to the treated liquid, and the culture liquid is harvested after light cultivation.

5. The processing method according to claim 4, characterized in that: The amount of the bacteria-algae symbiotic treatment agent added is 5-15% of the volume of the treatment liquid.

6. The processing method according to claim 4, characterized in that: The light culture is cultured in a closed environment.

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