CN111204876A

CN111204876A - Method for efficiently purifying and utilizing aquaculture tail water

Info

Publication number: CN111204876A
Application number: CN202010067015.5A
Authority: CN
Inventors: 胡超群; 张鑫; 任春华; 江晓; 陈廷; 阮尧; 陈偿; 丁雄祺
Original assignee: South China Sea Institute of Oceanology of CAS
Current assignee: South China Sea Institute of Oceanology of CAS
Priority date: 2020-01-20
Filing date: 2020-01-20
Publication date: 2020-05-29

Abstract

The invention discloses a method for efficiently purifying and utilizing aquaculture tail water. It is prepared by adding probiotic bacteria Alteromonas macleodii Y2(Am) and microalgae Nitzschia closterium LAMB131(Nc) into aquaculture tail water, and culturing. According to the invention, when the probiotics Am which can efficiently degrade nitrite and ammonia nitrogen and have flocculation and the low-light resistant bait microalgae Nc are subjected to combined culture in the ratio of 3:1, the removal rates of ammonia nitrogen, phosphate and nitrite can respectively reach 99%, 85% and 99%. While the Nc and the Am degrade inorganic salts in the water body, the Am converts the Nc into sea cucumber microbial floc bait through the flocculation of the Am, so that the feed protein is recycled while the pollution load of the culture water body is reduced.

Description

Method for efficiently purifying and utilizing aquaculture tail water

Technical Field

The invention relates to the technical field of aquaculture wastewater treatment and resource recycling, in particular to a method for efficiently purifying and utilizing aquaculture tail water.

Background

With the continuous development of aquaculture industry, the pollution of aquaculture tail water is serious. At present, intensive culture modes are prevalent, and farmers mostly feed high-protein feed in the whole process to achieve the aim of high yield. Direct discharge of the feces of the aquaculture animals and the fed residual baits into the aquaculture water produces a large amount of aquaculture tail water containing high concentrations of organic matter and N, P nutritive salts. On one hand, the decomposition of the organic matters can generate a large amount of substances such as ammonia nitrogen, nitrite and nitrate which are not beneficial to the healthy survival of the cultured animals, thereby causing the outbreak of diseases; on the other hand, the discharge of a large amount of aquaculture wastewater causes seawater pollution in a growing trend. Therefore, in order to realize the sustainable development of aquaculture, the concept and the action are changed, and the treatment of tail water of aquaculture is enhanced. Because the existing culture tail water treatment technology needs to occupy a new field and invest a large amount of facilities and equipment to build a culture tail water treatment system, land and a large amount of energy are consumed. Therefore, how to realize the high-efficiency purification and utilization of the aquaculture tail water on the premise of not increasing the land and energy investment becomes a great problem facing the sustainable development of the aquaculture industry.

Disclosure of Invention

The invention aims to provide a method for efficiently purifying and utilizing aquaculture tail water.

The method for efficiently purifying and utilizing aquaculture tail water comprises the steps of putting probiotics Alteromonas maceodii Y2(Am) and microalgae Nitzschia clausterium LAMB131(Nc) into the aquaculture tail water, and then culturing.

Preferably, the probiotic Am and the microalgae Nc are added according to the quantity ratio of 3: 1.

Preferably, the probiotic Am and the microalgae Nc are respectively cultured, then the microorganism is collected by centrifugation and diluted to 5 x 10 by using a culture medium or aquaculture tail water⁵CFU/mL, mixing the diluent containing the probiotics Am and the diluent containing the microalgae Nc according to the volume ratio of 3:1, and then inoculating the mixture into aquaculture tail water according to the ratio of 1% v/v for culture.

Preferably, tropical sea cucumbers are also cultured in aquaculture tail water.

Preferably, the sea cucumber is Holothuria leucospilota.

According to the invention, when the probiotics Am which can efficiently degrade nitrite and ammonia nitrogen and have flocculation and the low-light resistant bait microalgae Nc are subjected to combined culture in the ratio of 3:1, the removal rates of ammonia nitrogen, phosphate and nitrite can respectively reach 99%, 85% and 99%. While the Nc and the Am degrade inorganic salts in the water body, the Am converts the Nc into sea cucumber microbial floc bait through the flocculation of the Am, so that the feed protein is recycled while the pollution load of the culture water body is reduced.

According to the invention, by utilizing the ecological habit of co-habitation of tropical sea cucumbers and aquaculture animals and the organic detritus feeding property of the sea cucumbers, a new technology for purifying aquaculture tail water by utilizing sea cucumber baits, namely microalgae Nc and probiotics Am is developed, the key technical problem of purification of the aquaculture tail water is broken through, and the new technology for purifying and utilizing the aquaculture tail water is developed, so that the aim of organically unifying the culture environmental benefit and the economic benefit is achieved, and good ecological, economic and social benefits are generated.

The microalgae Nitzschia closterium LAMB131 can be purchased from the algal species bank of China oceanic university, and is numbered LAMB 131.

The Alteromonas macleodii Y2 of the invention is preserved in Guangdong province microbial culture collection center (GDMCC) in 2019 in 12.06.12.7.4.4. Guangzhou city, Jielizhooluo No. 100, lou No. 59, 5 th, zip code: 510070, accession number: 60922.

Drawings

FIG. 1 is a graph showing the effect of probiotics Am on the purification of ammonia nitrogen and nitrite in a water body;

FIG. 2 is a diagram showing the purifying effect of sea cucumber bait microalgae Nc on ammonia nitrogen and phosphate in a water body;

FIG. 3 is a graph showing the effect of probiotics Am and bait microalgae Nc in purifying nutritive salts in water body;

FIG. 4 is a graph showing the effect of bacteria and algae on the synergistic purification of nitrite in tail water from grouper cultivation;

FIG. 5 is a graph showing the effect of bacteria and algae on the synergistic purification of phosphate in the tail water of grouper cultivation;

FIG. 6 is a diagram showing the effect of sea cucumber in purifying organic substances in the tail water of grouper cultivation.

Detailed Description

In order to make the objects, technical solutions and advantageous technical effects of the present invention more clear, the present invention is further described in detail with reference to the following embodiments. It should be understood that the embodiments described in this specification are only for the purpose of describing the present invention and are not intended to limit the present invention. The parameters, proportions, etc. in the examples can be chosen appropriately without substantial effect on the results.

Example 1:

the M1 liquid culture medium comprises the following components per liter: NH (NH)₄Cl-N 5mg，NaNO₂ ^--N 5mg，NaH₂PO₄-P5 mg, glucose 2g, balance water, pH 8.0; the preparation method comprises mixing the above materials, adjusting pH, and sterilizing.

The M2 solid screening medium per liter included the following components: agar 15g, KNO₃1g，NaNO₂1g, yeast extract 0.1g, (NH)₄)₂SO₄2g, 10g of NaCl, 2g of glucose and the balance of water, wherein the pH value is 8.0; the preparation method comprises mixing the above materials, adjusting pH, and sterilizing.

The M3 liquid culture medium comprises the following components per liter: KNO₃100mg，KH₂PO₄10mg，FeSO₄·7H₂O 2.5mg，MnSO₄0.25mg，EDTA-Na₂10mg, the balance being water, the pH value being 8.0. The preparation method comprises mixing the above materials, adjusting pH, and sterilizing.

1. Determination of reasonable proportion of Nc and Am for synergistically purifying water body

The probiotic bacterium Alteromonas macleodii Y2(Am) and the low-light tolerant bait microalga Nitzschia closterium LAMB131(Nc) were cultured separately. Am and Nc were separated from the medium by centrifugation, and diluted to 5X 10 in M1 liquid medium, respectively⁵CFU/mL. Am and Nc were mixed at a volume ratio of 3:1, inoculated into M1 liquid medium at a ratio of 1% (v/v), and separately inoculated with Am dilutions (5X 10) at a ratio of 1% (v/v)⁵CFU/mL) and Nc dilutions (5X 10)⁵CFU/mL) to M1 liquid medium as a control. The culture conditions are as follows: the illumination intensity is 20%, the temperature is 30 ℃, and the illumination period is 12L to 12D. The medium was shaken every morning and evening. Samples were taken every 18h and the concentrations of ammonium, nitrite and phosphate were determined using a μmac smart portable water quality analyzer. The results of the measurement are shown in FIGS. 1 to 3.

a. As shown in FIG. 3, when the ratio of the algae bacteria is 1:3, the removal rates of ammonia nitrogen, phosphate and nitrite can reach 99%, 85% and 99% respectively.

b. As shown in fig. 1, 2 and 3, when the ratio of the phycomycetes is 1:3, the removal rate of ammonia nitrogen, phosphate and nitrite is significantly higher than that of Am and Nc alone, which indicates that when the ratio of the phycomycetes is 1:3, the phycomycetes and the phycomycetes have synergistic effect.

2. Application of Nc and Am in purification of tail water of grouper culture and bait of sea cucumbers

Taking 40L of grouper culture wastewater, and standing for 48h for later use. Respectively culturing the probiotics Am and the low-light resistant bait microalgae Nc. Am and Nc were separated from the culture medium by centrifugation, and diluted to 5X 10 by using filtered grouper culture wastewater (0.22 μ filter cartridge filtration) respectively⁵CFU/ml. Am and Nc are carried out according to the volume ratio of 3:1Mixing, inoculating the mixture into the grouper culture wastewater in a ratio of 1% (v/v); five heads (15.32 +/-2.5 g) of holothuria leucospilota (Holothuria leucospilota) are cultured in a barrel of an experimental group, and oxygenation is kept; meanwhile, a mixed system without inoculated bacteria and algae is used as a control without adding a sea cucumber group. The culture conditions are as follows: the temperature is 30-35 ℃, the salinity is 30, and the pH is 7.8-8.2. Sampling every 7 days, and determining the concentrations of ammonium salt, nitrite and phosphate by a mu MACSMART portable water quality analyzer; and determining the content change of organic matters in the sediments in the aquaculture water by adopting an ashing method.

As shown in FIGS. 4, 5 and 6, it can be seen that when the ratio of Am to Nc is 3:1, the nutrient salts (nitrite, phosphate and organic substances) in the tail water of grouper can be effectively purified, and thus, the tail water of grouper can be purified. Meanwhile, Am can convert Nc into microbial floc through the flocculation of itself, so bait can be provided for holothurian culture.

Claims

1. A method for efficiently purifying and utilizing aquaculture tail water is characterized in that probiotic Alteromonas macedii Y2 and microalgae Nitzschia clausterium LAMB131 are put into the aquaculture tail water and then cultured.

2. The method of claim 1, wherein the administration of the probiotic bacteria Alteromonas sporodii Y2 and the microalgae Nitzschia sporoterium LAMB131, Alteromonas sporodii Y2 and Nitzschia sporoterium LAMB131 is in a ratio of 3: 1.

3. The method of claim 2, wherein the administration of the probiotic bacteria alteromonas sporodii Y2 and the microalgae Nitzschia sporonium LAMB131 is carried out by culturing the probiotic bacteria alteromonas sporodii Y2 and the microalgae Nitzschia sporonium LAMB131 separately, centrifuging to collect the microorganisms, diluting to 5 x 10 with culture medium or aquaculture tail water⁵CFU/mL, mixing the dilution containing Alteromonas macleodii Y2 and the dilution containing Nitzschia closterium LAMB131 in a volume ratio of 3:1, and thenThen inoculating the mixture into aquaculture tail water according to the proportion of 1% v/v for culture.

4. The method according to claim 1, 2 or 3, characterized in that tropical sea cucumbers are also cultivated in the aquaculture tail water.

5. The method according to claim 4, wherein the sea cucumber is Holothuria leucospilota.