A method for treating seawater aquaculture sediment as feed source, a sea cucumber feed and a preparation method thereof

Abstract

The present invention provides a method for treating seawater aquaculture sediment as a feed source, a sea cucumber feed and a preparation method thereof, and belongs to the field of recycling waste resources in the aquaculture industry. The present invention dries and crushes the seawater aquaculture sediment, mixes it with stone powder, and places it in a microbial leaching device for elution to obtain deodorized seawater aquaculture sediment; the deodorized seawater aquaculture sediment, Bacillus subtilis, a nitrifying bacteria mixture and a special nutrient solution are mixed and fermented, and dried to obtain the feed source seawater aquaculture sediment. The present invention kills harmful bacteria in the sludge through a simple and efficient physical treatment method; designs a spray device to use water washing to reduce harmful heavy metals and salinity in the sludge; activates carbon, nitrogen and phosphorus in the sediment through enzymatic hydrolysis and fermentation; and realizes the feed source application of contaminated sediment by establishing a special sea cucumber feed with a sediment formula, thereby increasing the utilization value of the contaminated sediment, alleviating the pressure of the sea cucumber feed on sea mud, and promoting the sustainable development of the sea cucumber aquaculture industry.

Description

Technical Field

[0001] The present invention belongs to the field of recycling aquaculture waste resources, and in particular relates to a method for treating seawater aquaculture sediment as a feed source, a sea cucumber feed and a preparation method thereof. Background Art

[0002] Waste output from marine aquaculture primarily consists of uneaten feed, excrement and feces, and chemicals. Marine aquaculture often utilizes intensive or semi-intensive methods such as cages and net enclosures. This high-density culture requires large amounts of feed, a significant portion of which is inedible to the fish and settles into the sediment, becoming a major source of nitrogen, phosphorus, and sulfur. Furthermore, the large amounts of waste produced by intensive aquaculture are also a significant source of nitrogen, phosphorus, and sulfur. As leftover feed accumulates in the sediment, its phosphorus, nitrogen, and carbon levels increase, attracting microorganisms and reducing oxygen levels in the sediment, causing serious water pollution.

[0003] The root cause of environmental degradation is organic pollution in the aquaculture environment that exceeds the environment's purification capacity. Under aerobic conditions, organic matter in seawater is decomposed by aerobic bacteria and inorganicized, producing inorganic nutrients. However, when organic matter is present in large quantities and in the bottom layer with low oxygen concentrations, anaerobic bacteria replace aerobic bacteria and carry out anaerobic decomposition. Anaerobic bacteria are prevalent in marine areas and are sulfate-reducing bacteria. The decomposition product is hydrogen sulfide. Hydrogen sulfide is not only directly toxic to fish and other organisms, but also consumes dissolved oxygen due to its easy oxidation, thereby exacerbating the hypoxic state.

[0004] The bottom mud in the marine aquaculture area cannot be used directly as crop fertilizer due to its high salt content. Moreover, after long-term sedimentation, the sludge at the bottom of the aquaculture float valves in most bay areas is 1-2 meters thick, and its negative impact on the local aquaculture ecosystem is gradually becoming apparent.

[0005] Therefore, it is necessary to provide a high-value utilization method of seawater aquaculture sediments, as well as sea cucumber feed and its preparation method to alleviate the pressure of sea mud demand in sea cucumber feed, thereby promoting the healthy development of sea cucumber aquaculture production. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method for treating marine aquaculture sediment as a feed source, a sea cucumber feed and a preparation method thereof, so as to solve the problems of high content of harmful heavy metals and salinity in the sediment in marine aquaculture areas and high pressure on the demand for sea mud for sea cucumber feed.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0008] The present invention provides a method for treating marine aquaculture sediment as feed source, comprising the following steps:

[0009] 1) drying and crushing the marine aquaculture sediment and mixing it with stone powder to obtain sterilized marine aquaculture sediment;

[0010] 2) placing the sterilized marine aquaculture sludge in a microbial leaching device for elution to obtain deodorized marine aquaculture sludge;

[0011] 3) The deodorized seawater aquaculture sediment, Bacillus subtilis, nitrifying bacteria mixed solution and special nutrient solution are mixed, fermented and dried to obtain feed-sourced seawater aquaculture sediment.

[0012] Preferably, the drying method is: flattening the seawater aquaculture bottom mud, and then drying and turning it into powder or drying it into powder; the thickness of the flattened mud is 2-4 cm; the sunlight intensity of the drying and turning is ≥10 5 Lux, the cumulative drying time is not less than 48 hours, the number of turning over for drying is 3-5 times; the drying temperature is 70-90℃.

[0013] Preferably, the pulverization method is ultrafine pulverization, and the pulverized particle size is 150-200 mesh; the mass of the stone powder is 0.5-1.0% of the mass of the seawater aquaculture sediment.

[0014] Preferably, the microbial infiltration and washing device consists of a filtered water collection tank, a bottom water outlet, a coal ash bacteria culture bed, sterilized seawater aquaculture sludge, a PP cotton bacteria culture bed and a movable nozzle from bottom to top.

[0015] Preferably, the coal ash bacterial culture bed is inoculated with Bacillus subtilis and denitrifying bacteria; the inoculation amount of Bacillus subtilis in the coal ash bacterial culture bed is 20-30 g / ton of coal ash, and the inoculation amount of denitrifying bacteria in the coal ash bacterial culture bed is 10-15 g / ton of coal ash; the PP cotton bacterial culture bed is inoculated with Bacillus subtilis and nitrifying bacteria; the inoculation amount of Bacillus subtilis in the PP cotton bacterial culture bed is 30-40 g / square meter of PP cotton, and the inoculation amount of nitrifying bacteria in the PP cotton bacterial culture bed is 25-35 g / square meter of PP cotton; the culture time of the coal ash bacterial culture bed and the PP cotton bacterial culture bed is 3-5 days.

[0016] Preferably, the rinsing is performed by intermittent water spraying through a movable nozzle, the water spraying frequency is 6-8h / time, and the water spraying times is 2-3 times.

[0017] Preferably, the mass ratio of Bacillus subtilis to nitrifying bacteria in the mixed solution of Bacillus subtilis and nitrifying bacteria is 1:1 to 1:2; the amount of the mixed solution of Bacillus subtilis and nitrifying bacteria sprayed is 0.1%-0.5% of the mass of the seawater aquaculture sediment; the amount of the specially prepared nutrient solution sprayed is 1%-5% of the mass of the seawater aquaculture sediment;

[0018] The preparation method of the special culture solution comprises the following steps: mincing fish, shrimp, crab or their by-products into meat paste, adding water with a mass ratio of 1:30-1:50, and fermenting them in a sealed container at a temperature of 25-37° C. for 5-6 days, and then mincing to obtain the special nutrient solution.

[0019] Preferably, the mixed fermentation temperature is 25-37° C., and the fermentation time is 5-15 days.

[0020] The present invention also provides a sea cucumber feed, which comprises the following components in percentage by mass: calculated on a dry basis, 20-25% of algae powder, 3-5% of fish meal, 1-3% of shrimp meal, 0.1-0.2% of yeast wall, 1-2% of soybean meal, 4-6% of wheat flour, 0.5-1.5% of guar gum, 1-4% of cellulose, 0.3-0.5% of multi-minerals, 0.1-0.3% of multi-vitamins, 5-15% of commercial sludge, and 40-55% of feed-sourced seawater aquaculture sludge.

[0021] The present invention also provides a method for preparing sea cucumber feed, comprising the following steps: mixing and stirring the above components, adding 20%-25% of water by weight, stirring into a dough, then pressing into a biscuit shape by a pressing and granulating technique, and packaging and storing.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The aquaculture sludge used in the present invention is mainly the bottom sludge in areas with relatively heavy organic matter emissions, such as intensive marine aquaculture areas and bays. It is obtained by excavation, pumping, etc. In order to address the problems that this type of sludge may bring, such as high pollutant content, high nitrogen and phosphorus content, and odor, physical filtration + microbial bed deodorization methods are adopted to reduce pollutants while eliminating odor, so that it can be utilized as a feed source.

[0024] The present invention adopts upper and lower microbial bed infiltration and washing technology + fermentation treatment, which can reduce the adsorption of pollutants and reduce the salinity of the soil. At the same time, microorganisms treat toxic and harmful substances and appropriately transform organic matter such as nitrogen, phosphorus and sulfur. At the same time, special fermentation nutrient solution is added to accelerate the fermentation process and improve the effect of microorganisms.

[0025] The present invention kills harmful bacteria in sludge through a simple and efficient physical treatment method; designs a spray device to reduce harmful heavy metals and salinity in the sludge through water washing; activates carbon, nitrogen and phosphorus in the bottom mud through an enzymatic hydrolysis and fermentation method; and realizes the feed source application of contaminated bottom mud by establishing a special feed for sea cucumbers with a bottom mud formula, thereby increasing the utilization value of the contaminated bottom mud, alleviating the demand pressure of sea cucumber feed on sea mud, and promoting the sustainable development of the sea cucumber breeding industry.

[0026] The present invention uses activated seawater aquaculture sediment in sea cucumber feed for the first time, which greatly reduces the use of commercial sea mud, alleviates the demand pressure of commercial sea mud, and reduces the damage to nature caused by artificial mud mining. In addition, the invention adopts block making technology to improve the utilization rate of sea cucumber feed and reduce pollution. The invention is suitable for various sea cucumber farming methods such as ponds, factories, cages, and hanging cages, overcomes the problems of single use and heavy pollution of previous sea cucumber feed, and meets the requirements of sea cucumber ecological farming. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Diagram of the microbial infiltration device. DETAILED DESCRIPTION

[0028] The present invention provides a method for treating marine aquaculture sediment as feed source, comprising the following steps:

[0029] 1) drying and crushing the marine aquaculture sediment and mixing it with stone powder to obtain sterilized marine aquaculture sediment;

[0030] 2) placing the sterilized marine aquaculture sludge in a microbial leaching device for elution to obtain deodorized marine aquaculture sludge;

[0031] 3) The deodorized seawater aquaculture sediment, Bacillus subtilis, nitrifying bacteria mixed solution and special nutrient solution are mixed, fermented and dried to obtain feed-sourced seawater aquaculture sediment.

[0032] In the present invention, the seawater aquaculture sediment is dried, crushed, and then mixed with stone powder to obtain sterilized seawater aquaculture sediment. In the present invention, the seawater aquaculture sediment is preferably aquaculture contaminated sediment from cage aquaculture, float valve aquaculture, etc. in the bay area, obtained by excavation and dredging; the drying method is preferably: flattening the seawater aquaculture sediment, and then drying and turning it into powder or drying it into powder; the thickness of the flattened sediment is preferably 2-4 cm, more preferably 2.5-3.5 cm; the sunlight intensity for drying and turning is preferably ≥10 5 Lux, the cumulative drying time is no less than 48 hours, and the number of turning and drying is preferably 3-5 times; the drying temperature is preferably 70-90°C, more preferably 75-85°C. In the present invention, the pulverization method is preferably ultrafine pulverization, and the pulverized particle size is preferably 150-200 mesh, more preferably 160-180 mesh; the stone powder is a commercially available product, with impurities ≤1% and moisture ≤1%. The mass of the stone powder is preferably 0.5-1.0% of the mass of the marine aquaculture sediment, more preferably 0.6-0.8% of the mass of the marine aquaculture sediment.

[0033] In the present invention, the sterilized seawater aquaculture sludge is placed in a microbial leaching device for leaching and elution to obtain the deodorized seawater aquaculture sludge. In the present invention, the microbial leaching device is preferably composed of a filtered water collection tank, a bottom water outlet, a coal ash bacteria culture bed, sterilized seawater aquaculture sludge, a PP cotton bacteria culture bed and a movable nozzle from bottom to top. The coal ash bacteria culture bed is formed by inoculating Bacillus subtilis and denitrifying bacteria on coal ash; the coal ash is preferably commercially available, and the particle size of the coal ash is preferably 10-80μm, more preferably 30-60μm; the thickness of the coal ash is preferably 40-60cm, more preferably 45-55cm; the Bacillus subtilis and denitrifying bacteria are preferably commercial powdered Bacillus subtilis and denitrifying bacteria, both purchased from the market, and the effective live bacteria count of the Bacillus subtilis is >50 billion / g, the inoculation amount of Bacillus subtilis in the coal ash bacterial culture bed is preferably 20-30 g / ton of coal ash, more preferably 22-28 g / ton of coal ash; the effective viable count of denitrifying bacteria is >5 billion / g, the inoculation amount of denitrifying bacteria in the coal ash bacterial culture bed is preferably 10-15 g / ton of coal ash, more preferably 12-14 g / ton of coal ash; the coal ash bacterial culture bed and the PP cotton bacterial culture bed are inoculated and cultured for 3-5 days to form a biofilm.

[0034] In the present invention, the PP cotton bacterial culture bed is formed by inoculating Bacillus subtilis and nitrifying bacteria on PP cotton; the PP cotton is commercially available PP cotton, and the thickness of the PP cotton is preferably 15-30 cm, and more preferably 18-26 cm; the Bacillus subtilis and nitrifying bacteria are preferably commercial powdered Bacillus subtilis and nitrifying bacteria purchased from the market, the effective viable count of Bacillus subtilis is >50 billion / g, and the inoculation amount of Bacillus subtilis in the PP cotton bacterial culture bed is preferably 30-40 g / square meter of PP cotton, and more preferably 32-38 g / square meter of PP cotton; the effective viable count of nitrifying bacteria is 20 billion / g, and the inoculation amount of nitrifying bacteria in the PP cotton bacterial culture bed is 25-35 g / square meter of PP cotton, and more preferably 28-32 g / square meter of PP cotton; the inoculation and culture are carried out for 3-5 days to form a biofilm.

[0035] In the present invention, the rinsing is performed by intermittent water spraying through a movable nozzle, and the water spraying frequency is preferably 6-8h / time, and more preferably 6.5-7.5h / time; the number of water spraying is preferably 2-3 times, and the amount of water sprayed each time is equal to the mass of the bottom mud to be washed.

[0036] In the present invention, deodorized mariculture sediment, a mixture of Bacillus subtilis and nitrifying bacteria, and a specially prepared nutrient solution are mixed, fermented, and dried to obtain feed-sourced mariculture sediment. In the present invention, the mass ratio of Bacillus subtilis to nitrifying bacteria in the mixture is preferably 1:1 to 1:2; the amount of the mixture sprayed is preferably 0.1% to 0.5% of the mass of the mariculture sediment, more preferably 0.2% to 0.4%; and the method for preparing the specially prepared culture solution comprises the following steps: mincing fish, shrimp, crab, or their by-products into a pulp, adding 30-50 times the mass of the pulp in water, and fermenting the mixture under a sealed container at a temperature of 25-37°C for 5-6 days, followed by mincing to obtain the specially prepared nutrient solution; and the amount of the specially prepared nutrient solution sprayed is preferably 1% to 5% of the mass of the mariculture sediment, more preferably 2-4%.

[0037] In the present invention, the mixed fermentation temperature is preferably 25-37°C, more preferably 28-35°C; the fermentation time is preferably 5-15 days, more preferably 8-12 days; the drying method is preferably air-drying, sun-drying or drying at a temperature of 60-70°C, and the moisture content after drying is ≤4%.

[0038] The present invention also provides a sea cucumber feed, which comprises the following components in percentage by mass: calculated on a dry basis, 20-25% of algae powder, 3-5% of fish meal, 1-3% of shrimp meal, 0.1-0.2% of yeast wall, 1-2% of soybean meal, 4-6% of wheat flour, 0.5-1.5% of guar gum, 1-4% of cellulose, 0.3-0.5% of multi-minerals, 0.1-0.3% of multi-vitamins, 5-15% of commercial sludge, and 40-55% of feed-sourced seawater aquaculture sludge. In the present invention, the algae powder is preferably dry powder of large brown algae such as kelp, sargassum, and sargassum, and the particle size of the algae powder is preferably above 200 mesh; the fish meal is preferably commercial domestic fish meal, and the protein content of the fish meal is ≥55%; the shrimp meal is preferably commercial shrimp meal, and the protein content of the shrimp meal is preferably above 50%, and the volatile basic nitrogen is ≤150 mg / 100 g; the yeast wall is preferably commercial yeast cell wall, and the purity is ≥99%; the soybean meal is preferably commercial soybean meal, and the protein is ≥40%; the wheat flour is preferably commercial wheat flour, and the protein is ≥10%; the guar gum is preferably a commercial adhesive, and the purity is ≥80%; the cellulose is preferably commercial cellulose, and the purity is ≥95%; the multivitamin is preferably a multivitamin specially used for aquatic products, and the purity is ≥90%; the commercial bottom mud is preferably Bohai bottom mud.

[0039] The present invention also provides a method for preparing sea cucumber feed, comprising the following steps: mixing the above components, adding 20%-25% water by weight, and stirring into a dough; then pressing the dough into a biscuit shape using a granulation technique, and packaging and storing the biscuit. In the present invention, the granulation technique preferably uses a mold; the mold hole dimensions are preferably 2.5 cm long x 1.2 cm wide x 0.3 cm thick; and the pressing temperature is preferably 100-120°C to allow the feed components to reach a mature state.

[0040] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0041] Example 1

[0042] The aquaculture-polluted sediments from the intensive aquaculture areas in Laizhou Bay, Rushan Bay, Fujian and Xiapu were spread to 4 cm. 5 Lux) for 72 hours, turning it over twice during the drying period, and finally drying it into a dry powder, which is then put into an ultrafine grinder for ultrafine grinding into 200 mesh dry powder; 1% stone powder is added for secondary mixing and modulation, and then enters the subsequent infiltration, washing and fermentation process.

[0043] Microbial leaching was performed in a leaching and fermentation unit. The ash slag was laid with a particle size of 30 μm and a thickness of 40 cm. Before leaching, the ash was inoculated with Bacillus subtilis and denitrifying bacteria for three days to form a biofilm. The inoculum rate of Bacillus subtilis was 25 g per ton of ash, and the inoculum rate of denitrifying bacteria was 15 g per ton of ash. Polypropylene cotton was set to a thickness of 30 cm. Before leaching, Bacillus subtilis and nitrifying bacteria were inoculated for three days to form a biofilm. The inoculum rate of Bacillus subtilis was 35 g per square meter of PP cotton, and the inoculum rate of nitrifying bacteria was 30 g per square meter of PP cotton. The leaching was performed using intermittent water spraying, with a water volume equal to the mass of the sediment being leached, sprayed every six hours. After three sprays, the PP cotton bacterial culture bed was removed and a 0.2% mixture of Bacillus subtilis and nitrifying bacteria, along with a 3% specially formulated nutrient solution, was sprayed in for five days of fermentation at 28°C. Fish, shrimp, crab, or their by-products are minced into a paste, added to water at a mass ratio of 1:40, and sealed and fermented at 30°C for 5 days before being minced to obtain a special nutrient solution. After rinsing, the paste is dried in the sun until the moisture content is 4%.

[0044] The dried feed-derived aquaculture sludge is prepared into a sea cucumber feed according to the following proportions: calculated on a dry basis, algae powder 24%, fish meal 3%, shrimp meal 2%, yeast wall 0.2%, soybean meal 1%, wheat flour 6%, guar gum 0.6%, cellulose 2.6%, multi-mineral 0.3%, multi-vitamin 0.3%, commercial sludge 5%, and feed-derived aquaculture sludge 55%. The feed is fully stirred, and tap water (1 / 4 by weight) is added to stir into a dough. The dough is pressed into a biscuit shape (2.5 cm long × 1.2 cm wide × 0.3 cm thick) at a pressing temperature of 100°C, and the biscuits are packaged for storage.

[0045] Example 2

[0046] The obtained fish fecal sludge with high nitrogen and phosphorus content in the recirculating aquaculture system, such as the fish fecal sludge from large-scale recirculating aquaculture workshops such as rainbow trout and salmon in China, was spread to a depth of 2 cm. 5 Lux) and air-dried for 48 hours, turned over 3 times during the drying period, and finally dried into dry powder, which was then put into ultrafine grinding machine for ultrafine grinding into 150 mesh dry powder; 0.5% stone powder was added for secondary mixing and modulation, and then the subsequent infiltration, washing and fermentation process was entered.

[0047] Microbial leaching is performed in a leaching and fermentation device. To address the high nitrogen and phosphorus content and foul odor of fish feces, the paved coal ash has a particle size of 30 μm and a thickness of 40 cm. Before leaching, the coal ash is inoculated with Bacillus subtilis and denitrifying bacteria and cultured for four days to form a biofilm. The inoculum rate is 30 g per ton of coal ash, and the inoculum rate of denitrifying bacteria is 10 g per ton of coal ash. The PP cotton is set to a thickness of 15 cm. Before leaching, Bacillus subtilis and nitrifying bacteria are inoculated for five days to form a biofilm. The inoculum rate of Bacillus subtilis is 40 g per square meter of PP cotton, and the inoculum rate of nitrifying bacteria is 25 g per square meter of PP cotton. The filtration process uses intermittent water spraying, with a volume of tap water equal to the mass of the sediment being filtration washed, sprayed every eight hours. After two sprays, the PP cotton bacterial culture bed is removed and a mixture of 0.3% Bacillus subtilis, nitrifying bacteria, and 5% specially formulated nutrient solution is sprayed in for fermentation for 10 days at 30°C. Fish, shrimp, crab, or their by-products are minced into a paste and added to water at a mass ratio of 1:50. The paste is sealed and fermented at 25°C for six days, then minced to produce the specially formulated nutrient solution. After filtration, the slurry is dried in the sun until the moisture content reaches 3%.

[0048] The sea cucumber feed is prepared by preparing sun-dried activated fish feces sludge in the following proportions: calculated on a dry basis, 30% algae powder, 2% fish meal, 1% shrimp meal, 0.1% yeast wall, 1% soybean meal, 4% wheat flour, 0.5% guar gum, 1% cellulose, 0.3% multi-mineral, 0.1% multi-vitamin, 15% commercial sludge, and 45% feed-sourced aquaculture sludge. The mixture is fully stirred, 1 / 5 of the weight of tap water is added, and the mixture is stirred into a dough-like state. The mixture is pressed into a biscuit shape (2.5 cm long × 1.2 cm wide × 0.3 cm thick) at a pressing temperature of 110°C, and packaged for storage.

[0049] Experimental Example 1

[0050] On March 10, 2021, a feeding comparison experiment was carried out on the special compound feed for sea cucumbers prepared in Example 1 of the present invention at a sea cucumber farm in Penglai. The comparison feed was two commercial feeds on the market (commercial feed 1: 30% sargassum powder; 20% kelp powder; 6% fish meal; 3.5% yeast powder; 8% soybean meal; 0.5% complex enzyme; 1% complex vitamin; 1% mineral salt; 30% sea mud. Commercial feed 2: 6% sargassum; 25% kelp powder, 8% fish meal, 3% wheat flour; 5% soybean meal; 0.5% vitamin, 52.5% sea mud). The sea cucumber breeding method is a conventional breeding technology. Except for the different feeds used, other breeding conditions are the same. After more than three months of breeding, the sea cucumbers were weighed on June 9. The weight gains of the sea cucumbers raised on commercial feed reached 163.2% and 157.4%, respectively, and the mortality rates were 5.2% and 6.6%. The feeding effect of the sea cucumber feed containing feed-sourced aquaculture sediment of the present invention reached 169.5%, and the mortality rate was 5.8%. Therefore, it can be seen that the breeding effect of the sea cucumbers raised on the activated aquaculture sediment feed is close to or even exceeds the breeding effect of the sea cucumber commercial feed.

[0051] Experimental Example 2

[0052] The activated fish excrement bottom mud in the embodiment of the present invention 2 is mixed with sea cucumber feed and a feeding experiment is carried out at Jinghai Muping breeding base. The contrast feed is the seaweed powder made by mixing kelp and other seaweeds. The described sea cucumber culture method is a conventional culture technology. Except that the feed used is different, other culture conditions are all consistent. After feeding for more than 2 months, the sea cucumbers cultured with seaweed powder gained weight by 91.7%, and the mortality rate was 3.7%. The sea cucumbers fed with activated fish excrement bottom mud that were mixed with sea cucumber feed gained weight by 86.4%, and the mortality rate was 3.4%. Therefore, it can be seen that although the activated fish excrement bottom mud that was mixed with sea cucumber feed culture effect was slightly inferior to seaweed powder, the mortality rate was lower than seaweed powder.

[0053] From the above embodiments and experimental examples, it can be seen that the seawater aquaculture sediment obtained by the feed source treatment method of the present invention can be used in sea cucumber feed to effectively promote the rapid growth of sea cucumbers and reduce their mortality rate. By establishing a special feed for sea cucumbers with a sediment formula, the feed source application of contaminated sediment can be achieved, thereby increasing the utilization value of contaminated sediment, alleviating the demand pressure of sea cucumber feed on sea mud, and promoting the sustainable development of the sea cucumber aquaculture industry.

[0054] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for treating marine aquaculture sediment as feed source, characterized in that: The following steps are involved: 1) Drying and crushing the marine aquaculture sediment and mixing it with stone powder to obtain sterilized marine aquaculture sediment; The drying method comprises: flattening the seawater aquaculture bottom mud, and sequentially drying and turning it into powder or drying it into powder; the thickness of the flattened mud is 2-4 cm; the sunlight intensity of the drying and turning is ≥10 5 Lux, the cumulative drying time is not less than 48 hours, the number of turning over for drying is 3-5 times; the drying temperature is 70-90°C; 2) placing the sterilized marine aquaculture sludge in a microbial leaching device for elution to obtain deodorized marine aquaculture sludge; The microbial leaching device consists of a filtered water collection tank, a bottom water outlet, a coal ash slag bacteria culture bed, sterilized seawater aquaculture bottom mud, a PP cotton bacteria culture bed and a movable nozzle from bottom to top; The coal ash bacterial culture bed is inoculated with Bacillus subtilis and denitrifying bacteria; the inoculation amount of Bacillus subtilis in the coal ash bacterial culture bed is 20-30g / ton of coal ash, and the inoculation amount of the denitrifying bacteria in the coal ash bacterial culture bed is 10-15g / ton of coal ash; the PP cotton bacterial culture bed is inoculated with Bacillus subtilis and nitrifying bacteria; the inoculation amount of Bacillus subtilis in the PP cotton bacterial culture bed is 30-40g / square meter of PP cotton, and the inoculation amount of the nitrifying bacteria in the PP cotton bacterial culture bed is 25-35g / square meter of PP cotton; the culturing time of the coal ash bacterial culture bed and the PP cotton bacterial culture bed is 3-5 days; 3) The deodorized marine aquaculture sediment, Bacillus subtilis, nitrifying bacteria mixture and special nutrient solution are mixed, fermented and dried to obtain feed-sourced marine aquaculture sediment.

2. The method for treating marine aquaculture sediment as feed source according to claim 1, characterized in that: The pulverization method in step 1) is ultrafine pulverization, and the particle size of the pulverization is 150-200 mesh; the mass of the stone powder is 0.5-1.0% of the mass of the seawater aquaculture sediment.

3. The method for treating marine aquaculture sediment as feed source according to claim 1, characterized in that: The rinsing in step 2) is performed by intermittently spraying water through a movable nozzle, the spraying frequency is 6-8 hours / time, and the number of spraying times is 2-3 times.

4. The method for treating marine aquaculture sediment as feed source according to claim 1, wherein: In step 3), the mass ratio of Bacillus subtilis to nitrifying bacteria in the mixed solution of Bacillus subtilis and nitrifying bacteria is 1:1 to 1:2; the amount of the mixed solution of Bacillus subtilis and nitrifying bacteria sprayed is 0.1% to 0.5% of the mass of the seawater aquaculture sediment; the amount of the specially prepared nutrient solution sprayed is 1% to 5% of the mass of the seawater aquaculture sediment; The preparation method of the special nutrient solution comprises the following steps: mincing fish, shrimp, crab or their by-products into meat paste, adding water with a mass ratio of 1:30-1:50, and fermenting the mixture under a sealed container at a temperature of 25-37° C. for 5-6 days, and then mincing the mixture to obtain the special nutrient solution.

5. The method for treating marine aquaculture sediment as feed source according to claim 1, characterized in that: The temperature of the mixed fermentation in step 3) is 25-37° C., and the time of the mixed fermentation is 5-15 days.

6. A sea cucumber feed, characterized in that The invention comprises the following components in percentage by mass: calculated on a dry basis, 20-25% of algae powder, 3-5% of fish meal, 1-3% of shrimp meal, 0.1-0.2% of yeast wall, 1-2% of soybean meal, 4-6% of wheat flour, 0.5-1.5% of guar gum, 1-4% of cellulose, 0.3-0.5% of multi-minerals, 0.1-0.3% of multi-vitamins, 5-15% of commercial sludge, and 40-55% of feed-sourced marine aquaculture sludge prepared by the method according to any one of claims 1 to 5.

7. The method for preparing the sea cucumber feed according to claim 6, wherein The method comprises the following steps: mixing and stirring the components in claim 6, adding 20% ​​to 25% of the mass of water and stirring into a dough, then pressing into a biscuit shape by a pressing and granulating technology, and packaging and storing.

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