A bacterial agent for treating and recovering carbon, nitrogen and phosphorus in high-salinity wastewater and its application

Abstract

This invention discloses a microbial agent for treating and recovering carbon, nitrogen, and phosphorus from high-salinity wastewater and its application. The agent comprises marine microalgae and fungal hyphae. This invention's agent can efficiently treat carbon, nitrogen, and phosphorus in high-salinity wastewater, and is easy to operate. The recovered biomass can be recycled. It solves the problems of low efficiency in treating carbon, nitrogen, and phosphorus in high-salinity water using current microbial methods and the difficulty in recovering high-salinity-tolerant microalgae; it achieves good results for wastewater with salinity below 4%. Furthermore, this invention eliminates the need to add PVA and sodium alginate to form gel spheres before adding them to the wastewater. Instead, suitable algae and bacteria are directly added to the wastewater, and while treating carbon, nitrogen, and phosphorus, they form small spheres in the wastewater, which can then be collected and recovered together, making the operation simpler.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental protection, and specifically relates to a bacterial agent for treating and recovering carbon, nitrogen and phosphorus in high-salinity wastewater and an application thereof. Background Art

[0002] High-salinity wastewater is usually treated by expensive physical and chemical methods due to its high salinity and unsuitable growth of organisms. However, due to the high cost of high-facilitation high-salinity wastewater treatment solutions in the initial investment and daily operation and maintenance, the industry is not willing to accept them. Farmers such as seawater aquaculture and companies such as kimchi pickling tend to use economically feasible biological methods to treat tailwater. However, biotechnology for treating high-salinity water still has bottleneck problems such as low treatment efficiency and difficulty in recovering high-salinity-tolerant microalgae.

[0003] The method of combining microalgae and fungal hyphae has been used for low-salinity wastewater, but high salinity will inhibit flocculation between microalgae and fungal hyphae, so whether this method can be used for high-salinity wastewater has not been studied. Summary of the invention

[0004] The object of the present invention is to provide a bacterial agent and a treatment method which can effectively treat carbon, nitrogen and phosphorus in high-salinity wastewater.

[0005] The technical solution adopted by the present invention is:

[0006] A first aspect of the present invention provides a bacterial agent, wherein the bacterial agent comprises marine microalgae and fungal hyphae.

[0007] Preferably, the marine microalgae include at least one of Chlorella vulgaris, Dunaliella salina, Platymonas subcordiformis, Nannochloropsis spp., and Trichophyton.

[0008] Preferably, the fungal hyphae include at least one of Ganoderma lucidum hyphae, Monascus hyphae, Lentinus edodes hyphae, Aspergillus niger hyphae, and Pleurotus ostreatus hyphae.

[0009] Preferably, the ratio of the number of seawater microalgae to fungal hyphae is (1.2*10 6 ~2.4*10 6 ):1.

[0010] The second aspect of the present invention provides use of the bacterial agent described in the first aspect of the present invention in treating wastewater or preparing a product for treating wastewater.

[0011] The third aspect of the present invention provides a method for treating wastewater, wherein the bacterial agent described in the first aspect of the present invention is added to the wastewater for treatment.

[0012] Preferably, the concentration of the seawater microalgae is 6*10 9 -12*10 9 cell / L.

[0013] More preferably, the marine microalgae are mid-logarithmic marine microalgae.

[0014] Preferably, the concentration of the Aspergillus niger mycelium pellets is 3000 to 7000 pellets / L.

[0015] Preferably, the method for preparing the fungal mycelium pellet comprises: adding (5-9)*10 7 The amount of spores is the amount of spores in the fungal mycelium pellet cultured for 40 to 60 hours.

[0016] Preferably, the treatment may be performed under full illumination or with a light-dark time ratio of ≥ 1:1.

[0017] Preferably, the light-dark time ratio is (2-4):1.

[0018] Preferably, the light intensity during the treatment is 3000-9000 lux.

[0019] Preferably, the treatment time is 10 to 16 hours.

[0020] Preferably, the wastewater is high-salt wastewater.

[0021] More preferably, the salinity of the high-salt wastewater is ≤4%.

[0022] More preferably, the salinity of the high-salt wastewater is 1% to 4%.

[0023] Preferably, the method further comprises the step of recovering the treated seawater microalgae and fungal mycelium pellets to obtain a seawater microalgae-fungal mycelium pellet complex.

[0024] Preferably, the recycling comprises using a net with a pore size of 1 to 4 mm for recycling.

[0025] The fourth aspect of the present invention provides a marine microalgae-fungal mycelium ball complex, which is prepared by the method described in the third aspect of the present invention. In the prior art, there has been no successful study of combining the two into small balls for use in high-salinity wastewater, and it has been found that high salinity will inhibit the flocculation of activated sludge. The present application selects bacterial and algae species so that they can form a good complex in high-salinity wastewater, and the complex is used to prepare feed, which is easy to operate and achieves waste recycling.

[0026] The fifth aspect of the present invention provides the use of the seawater microalgae-fungal mycelial ball complex described in the fourth aspect of the present invention in preparing feed.

[0027] Preferably, the feed is for use in aquaculture.

[0028] Preferably, the aquatic products include fish, shrimps, crabs, and shellfish.

[0029] Preferably, the aquatic products include sea bass, black carp, hairtail, cuttlefish, octopus, prawns, blue crabs, swimming crabs, abalone, clams, lobster shrimp, and whiteleg shrimp.

[0030] The beneficial effects of the present invention are:

[0031] The present invention provides a bacterial agent for treating high-salinity wastewater, comprising seawater microalgae and fungal hyphae; using the bacterial agent to treat wastewater can efficiently treat carbon, nitrogen and phosphorus in high-salinity wastewater, and the operation is simple, and the carbon, nitrogen and phosphorus recovered from biomass after treatment can be recycled. The problem of low efficiency of treating carbon, nitrogen and phosphorus in high-salinity water by microbial methods and difficulty in recovering high-salinity resistant microalgae is solved; good results can be achieved for wastewater salinity below 4%.

[0032] Moreover, the present invention does not need to add PVA and sodium alginate to form gel balls and then add them into the wastewater. Instead, suitable algae and bacteria can be directly added into the wastewater. The two can form small balls in the wastewater while treating carbon, nitrogen and phosphorus in the wastewater, and then they can be salvaged and recovered together later, which makes the operation simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is the initial situation when mycelial pellets and microalgae are added into wastewater.

[0034] Figure 2 This is the flocculation of mycelium balls and microalgae into balls at the end of the operation.

[0035] Figure 3 This shows the situation of swimming crabs eating fungal and algal pellets. DETAILED DESCRIPTION

[0036] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0037] Example 1

[0038] In the tail water of aquaculture with salinity of 3%, COD of 800mg / L, TN of 50mg / L, NH3-N of 50mg / L, and TP of 10mg / L, 7*10 7 The number of spores is 9*10 of Aspergillus niger mycelial pellets cultured for 48 hours (the number of mycelial pellets is about 6000 at this time) and / or Chlorella sp. TNBR1 in the middle logarithmic period. 9cell, light-dark time ratio 9:3, light intensity 6000 lux, carbon, nitrogen and phosphorus removal and bacterial algae flocculation efficiency after 12 hours of reaction are shown in Table 1. Figure 1 This is the initial situation when mycelial pellets and microalgae are added into wastewater. Figure 2 This is the flocculation of mycelium balls and microalgae into balls at the end of the operation.

[0039] Table 1

[0040]

[0041] After the treatment, the seawater microalgae-fungal mycelium ball complex was salvaged with a net (mesh diameter 2mm), and the nutritional value of the complex was tested as follows: 2.28mg / g oil, 4.27mg / g protein, 19.24mg / g polysaccharide, 5.33mg / g carotenoid, 5.45mg / g chlorophyll. Feeding Macrobrachium rosenbergii instead of part of the feed can save feed costs. The experimental group is shown in Table 2, 0.1g is fed each time, and the feed used is black shrimp flakes purchased from Taobao, with ingredients: 48% protein, lysine 2% or less, and crude ash 16% or less. It was fed for 15 consecutive days, twice a day in the morning and evening. The results showed that the Macrobrachium rosenbergii group fed with pure algae and fungi pellets had the highest protein content, low fat content, high water content, and higher protein content than the protein content of shrimp described in the "Nutrient Composition Table of Ordinary Foods in China" of 16.8g / 100g, which is a high-quality nutritious food.

[0042] Table 2

[0043]

[0044] Example 2

[0045] In the wastewater of kimchi pickling factory with salinity of 2.4%, COD of 6366mg / L, TN of 406mg / L, NH3-N of 94mg / L and TP of 15mg / L, 8*10 7 The amount of spores is 10*10 of Pleurotus ostreatus mycelium pellets cultured for 48 hours (the number of mycelium pellets is about 6200 at this time) and / or Dunaliella salina in the middle logarithmic period. 9 cell, the carbon, nitrogen and phosphorus removal and the algae flocculation efficiency after 12 hours of illumination at a light intensity of 9000 lux are shown in Table 3.

[0046] Table 3

[0047]

[0048] After processing, the seawater microalgae-fungus mycelium complex was fished out with a net (mesh diameter 2mm), and the nutritional value of the complex was tested as follows: oil 12.19mg / g, protein 6.32mg / g, polysaccharide 12.63mg / g, carotenoid 6.73mg / g, chlorophyll 4.70mg / g. Feeding swimming crabs instead of part of the feed can save feed costs ( Figure 3 ).

[0049] Example 3

[0050] In the tail water of aquaculture with salinity of 3%, COD of 800mg / L, TN of 50mg / L, NH3-N of 50mg / L, and TP of 10mg / L, 6.5*10 7 The number of spores is 48 hours of culture of Ganoderma lucidum mycelium pellets (the number of mycelium pellets is about 50-60 at this time) and / or mid-logarithmic Nannochloropsis Oceanica 11*10 9 cell, the carbon, nitrogen and phosphorus removal and the algae flocculation efficiency after 12 hours of illumination at a light intensity of 8000 lux are shown in Table 4.

[0051] Table 4

[0052]

[0053] Example 4

[0054] In the salt-rich organic fermentation wastewater with salinity of 2.3%, COD of 5190mg / L, TN of 428mg / L, NH3-N of 312mg / L, and TP of 40mg / L, 7*10 7 The amount of spores is 10*10 of Lentinusedodes mycelium balls cultured for 48 hours (the number of mycelium balls is about 5400 at this time) and / or Isochrysis galbana in the middle logarithmic period. 9 cell, the carbon, nitrogen and phosphorus removal and the algae flocculation efficiency after 12 hours of illumination at a light intensity of 7000 lux are shown in Table 5.

[0055] Table 5

[0056]

[0057] Comparative Example 1

[0058] The seawater Chlorella was replaced by Spirulina, and the other conditions were the same as in Example 1. However, it was found that the special spiral structure of Spirulina made it difficult to adsorb on the mycelium ball (the flocculation efficiency of Spirulina and mold was less than 50%).

[0059] Comparative Example 2

[0060] The seawater Chlorella was replaced by Lunaea fasciata, and the other conditions were kept the same as in Example 1. The results showed that the flocculation effect was only close to 55%.

[0061] The above specific implementations have been described in detail for the present invention, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. Use of a bacterial agent in treating wastewater or preparing a product for treating wastewater; The bacterial agent is composed of seawater chlorella and black aspergillus mycelium balls, and the quantity ratio of the seawater chlorella and the black aspergillus mycelium balls is 9*10 9 : 6000; The wastewater is high-salinity wastewater; The salinity of the high-salt wastewater is 1% to 4%.

2. A method for treating wastewater, characterized in that: Adding bacterial agents to wastewater for treatment; The bacterial agent is composed of seawater chlorella and black aspergillus mycelium balls, and the quantity ratio of the seawater chlorella and the black aspergillus mycelium balls is 9*10 9 : 6000; The wastewater is high-salinity wastewater; The salinity of the high-salt wastewater is 1% to 4%.

3. The method according to claim 2, characterized in that The marine chlorella is a marine chlorella in the mid-logarithmic period.

4. The method according to claim 3, characterized in that The treatment is full light or the light-dark time ratio is ≥1:

1.

5. The method according to claim 4, characterized in that The light intensity during the treatment is 3000-9000 lux.

6. The method according to claim 4, characterized in that The treatment time is 10 to 16 hours.

7. The method according to any one of claims 2 to 6, characterized in that: The method further comprises the step of recovering the seawater Chlorella and Aspergillus niger mycelium pellets to obtain a seawater microalgae-fungal mycelium pellet complex.

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