CN107509673A - A kind of resource utilization method of intensive Environment of Litopenaeus vannamei Low breeding wastewater - Google Patents

Abstract

The invention relates to a resource utilization method of intensive Litopenaeus vannamei culture wastewater, the method comprising: step S1: filtering the wastewater discharged from the intensive Litopenaeus vannamei culture pond with a slope filter screen; step S2: filtering The wastewater filtered by the slope filter screen is collected into the wastewater storage tank; step S3: transport the wastewater from the wastewater storage tank to the microalgae proliferation pool in the sun shed to cultivate microalgae; step S4: transport the cultivated algae water to cladocera or radial In the pod culture ponds, the resulting cladocera or copepods are harvested to supplement the bait for Litopenaeus vannamei culture. Its advantages are as follows: the nitrogen and phosphorus nutrients in the waste water are used in the microalgae-zooplankton-prawn food chain to purify the eutrophic aquaculture waste water while realizing the recycling of nutrients such as nitrogen and phosphorus, which not only protects the The aquaculture water environment also supplements natural bait for intensive shrimp farming, reduces the feed cost of shrimp farming, and improves farming efficiency.

Description

A resource utilization method of intensive Litopenaeus vannamei culture wastewater

technical field

The invention relates to the technical field of resource-based treatment of aquaculture wastewater, in particular to a method for resource-based utilization of intensive Litopenaeus vannamei culture wastewater.

Background technique

Litopenaeus vannamei has become the main cultured species of prawns in China, South America and Southeast Asia because of its fast growth, high meat yield and wide adaptability to salinity. Since the introduction of aquaculture in my country in the late 1980s, China’s Litopenaeus vannamei industry has developed rapidly. According to the statistics of the China Fishery Yearbook, in 2016, my country’s seawater crustacean aquaculture output was 1.4349 million tons, of which more than 40% came from Litopenaeus vannamei, while freshwater The production of cultured Litopenaeus vannamei was 731,500 tons. However, with the rapid development of my country's Litopenaeus vannamei industry, many problems such as provenance, disease and breeding mode have also been exposed. At present, the success rate of cultivating Litopenaeus vannamei in traditional earthen ponds is getting lower and lower, and more farmers are choosing more intensive and more controllable factory and greenhouse farming models.

According to the nutritional and metabolic characteristics of Litopenaeus vannamei, at present, the feed protein level of Litopenaeus vannamei cultured in my country is generally 37%-40%, and the feed coefficient of normal culture is 1.0-1.1, while the protein level of Litopenaeus vannamei grown in China is generally 37%-40%. The content accounts for about 18% of the whole shrimp. Based on this calculation, the content of protein nitrogen retained in the shrimp body in the feed input during the breeding process does not exceed 50%, and more than half of the nitrogen enters the water body. Therefore, from the perspective of material circulation, the culture process of Litopenaeus vannamei is a process that seriously pollutes the culture water body. Especially in the intensive farming mode, a large amount of aquaculture wastewater has not been effectively treated and is directly discharged into the surrounding waters, resulting in severe eutrophication of the water environment and the outbreak of algal blooms, threatening the sustainable development of Litopenaeus vannamei farming and the environment . Under the background of the implementation of the "Water Law of the People's Republic of China" revised in 2016, how to reduce and prevent the pollution of aquaculture wastewater to the environment has become an urgent problem for the development of the aquaculture industry itself.

At present, a variety of methods and processes for treating aquaculture wastewater have been developed at home and abroad, including physical treatment, chemical treatment, biofilm, artificial wetland treatment, salt-tolerant plant or aquatic plant treatment, and precipitation-algae adsorption. Comprehensive processing methods, etc. The above method can play a role in purifying the aquaculture wastewater, but the overall investment is large and the utilization of nutrient salt in the wastewater is not high, and the application degree in Litopenaeus vannamei aquaculture is very low.

In summary, there is an urgent need to invent a resource utilization method for intensive Litopenaeus vannamei aquaculture wastewater. This method can not only purify the nitrogen and phosphorus nutrients in the aquaculture wastewater with high efficiency and low cost, but also reduce the nitrogen in the wastewater. Phosphorus can be utilized as a resource to reduce the cost of bait for Litopenaeus vannamei culture. However, there is no report on the resource utilization method of this intensive Litopenaeus vannamei culture wastewater.

Contents of the invention

The purpose of the present invention is to address the deficiencies in the prior art, to provide a resource utilization method of intensive Litopenaeus vannamei culture wastewater, so that a large amount of nitrogen and phosphorus nutrients and small amounts of nitrogen and phosphorus nutrients that exist in the intensive Litopenaeus vannamei culture wastewater Granular organic debris can be converted into Cladocera or Copepod biomass after being filtered by Cladocera or Copepods, so as to achieve the goal of purifying aquaculture wastewater. At the same time, the generated Cladocera or Copepods can be used for Supplementation of bait for Litopenaeus vannamei culture.

For realizing above-mentioned object, the technical scheme that the present invention takes is:

A resource utilization method of intensive Litopenaeus vannamei culture waste water, is characterized in that, described method comprises the following steps:

Step S1: Filter the wastewater discharged from the intensive Litopenaeus vannamei culture pond with a slope filter screen;

Step S2: collecting the waste water filtered by the slope filter screen in step S1 into the waste water storage tank;

Step S3: transporting the waste water from the waste water storage tank in step S2 to the microalgae multiplication pond in the sunshine shed to cultivate microalgae;

Step S4: Transport the cultivated algae water to the Cladocera or Copepod culture tank, and purify the microalgae in the water with the help of Cladocera or Copepod filter feeding to generate high-transparency water for recycling or discharge, and the generated branches Feeds for Litopenaeus vannamei culture are supplemented after horn or copepod harvest.

As a preferred technical solution, the sloped filter screen in step S1 is composed of two parts, the screen mesh of the first part is 60-80 mesh, the screen mesh of the second part is 200 mesh, and the inclined plane of the screen is in line with the The horizontal plane forms an included angle of 30°-60°, which is adjusted according to the screen area, water flow and the number of suspended particles in the waste water. The solid waste on the screen will automatically gather into the sewage tank under the action of the water flow.

As a preferred technical solution, the wastewater filtered by the inclined screen is transported to the wastewater storage tank through pipelines. The wastewater storage tank is a cement pool or an earthen pool covered with plastic film, which is covered with a plastic film to prevent other animals from entering the wastewater storage tank. pool.

As a preferred technical solution, the container for cultivating microalgae in the sunshine shed in step S3 can be a photobioreactor, or a simple cement pool or a detachable water tank.

As a preferred technical solution, step S3 includes the following steps:

Step S31, the step of microalgae proliferation: microalgae proliferation needs to be pre-inoculated with beneficial microalgae with strong anti-pollution ability and high temperature resistance to directional control the types of microalgae that proliferate. Nannochloropsis oculata or Tetraselmis subcordiformis or Dunaliella salina, if the culture wastewater of Litopenaeus vannamei is fresh water, it can be inoculated with Chlamydomonasspp., Chlorella spp.), Scenedesmus spp., and Chlorococcum sp., microalgae need to be aerated continuously during the proliferation process, and the algae liquid can be transported to the cladocera or copepod culture tank after 3-5 days of cultivation .

As a preferred technical scheme, when the wastewater from Litopenaeus vannamei culture has salinity, the species of Calanoides (Calanoid) or Moina mongolica (Moina mongolica) are cultivated to filter-feed microalgae, and when Litopenaeus vannamei is cultured When the wastewater is fresh water, filter-feeding algae of Daphnia magna or Daphnia carinata are cultivated, and aeration is continued during the cultivation process.

As a preferred technical solution, the volume ratio of the water body for the proliferation of microalgae to the water body for the cultivation of cladocera or copepods is 2-3:1.

As a preferred technical scheme, the siphon method is used to collect cladocera or copepods with 100 mesh sieve silk bags every day from the cladocera or copepod culture ponds, and the daily harvest depends on the growth of the population and the water body. Depends on algae cell density.

The present invention has the advantage that:

1. The resource utilization method of Litopenaeus vannamei aquaculture wastewater of the present invention, the nitrogen and phosphorus nutrients in the wastewater, by means of the food chain of microalgae-zooplankton-prawns, while purifying the eutrophic aquaculture wastewater, realize The recycling of nutrients such as nitrogen and phosphorus not only protects the aquaculture water environment, ensures the sustainable development of the aquaculture industry, but also supplements natural bait for intensive shrimp farming, reduces the cost of shrimp farming feed, and improves farming efficiency.

2. The resource utilization method of Litopenaeus vannamei culture wastewater of the present invention has relatively low input cost and strong technical operability.

Description of drawings

Accompanying drawing 1 is a flow chart of the resource utilization method of a kind of intensive Litopenaeus vannamei culture waste water of the present invention.

detailed description

The specific embodiments provided by the present invention will be described in detail below in conjunction with the accompanying drawings.

In this embodiment, a Litopenaeus vannamei breeding base has carried out a resource utilization test of Litopenaeus vannamei aquaculture wastewater in Pudong New District. ^The Litopenaeus vannamei culture pond is a 50M cement pond, and it is put in at a density of 400 ^tails /M The waste water replaced in the breeding process of 3 cm thick shrimp seedlings desalinated by the vannamei is purified with reference to the method of the present invention. Please refer to FIG. 1 . FIG. 1 is a flow chart of a resource utilization method of intensive Litopenaeus vannamei culture wastewater according to the present invention. A method for resource utilization of intensive Litopenaeus vannamei culture wastewater, said method comprising the following steps:

Step S1: Filter the wastewater discharged from the intensive Litopenaeus vannamei culture pond with a slope filter screen;

Among them, the slope filter screen is composed of two parts, the screen mesh of the first part is 60-80 mesh, the screen mesh of the second part is 200 mesh, the slope of the screen and the horizontal plane form an angle of 30°-60°, Specifically, it is adjusted according to the screen area, water flow rate and the number of suspended particles in the wastewater. The solid waste on the screen will automatically gather into the sewage tank under the action of the water flow.

Step S2: collecting the waste water filtered by the slope filter screen in step S1 into the waste water storage tank;

Among them, the waste water filtered by the slope filter screen is transported to the waste water storage tank through pipelines. The waste water storage tank is a cement pool or an earthen pool covered with plastic film, which is covered with a plastic film to prevent other animals from entering the waste water storage tank.

Step S3: transporting the waste water from the waste water storage tank in step S2 to the microalgae multiplication pond in the sun shed to cultivate microalgae;

Wherein, the container for cultivating microalgae in the sunshine shed can be a photobioreactor, or a simple cement pool or a detachable water tank.

Step S4: The cultivated algae water is transported to the cladocera or copepod culture pool, and the microalgae in the water are purified by the filter feeding of the cladocera or copepods to generate high-transparency water for recycling or discharge, and the generated cladocera Litopenaeus vannamei cultured baits are supplemented after harvesting of species or copepods.

Among them, microalgae proliferation needs to be pre-inoculated with beneficial microalgae with strong anti-pollution ability and high temperature resistance to directional control the types of microalgae that proliferate. Tetraselmis subcordiformis (Tetraselmis subcordiformis) or Salina (Dunaliella salina), etc., if the culture wastewater of Litopenaeus is fresh water, it can be inoculated with Chlamydomonas spp., Chlorellaspp., Scenedesmus ( Scenedesmus spp.), Chlorococcum sp., etc., need continuous aeration during the proliferation of microalgae, and after 3-5 days of cultivation, the algae liquid can be transported to the cladocera or copepod culture tank.

Among them, when the waste water of Litopenaeus vannamei has salinity, the species of Calanoid or Moina mongolica filter-feeding microalgae are cultivated; when the waste water of Litopenaeus vannamei is fresh water, the culture of Daphnia magna or Daphnia carinata filter-feeds algae, which are continuously aerated during cultivation.

Wherein, the volume ratio of the water body in which Scenedesmus proliferates to the water body in which Daphnia magna is cultivated is 2-3:1.

Among them, the siphon method is used to collect daphnia magna from the daphnia culture pond every day with a 100-mesh sieve silk bag. The daily harvest depends on the growth of the population and the density of algae cells in the water body. The harvested daphnia magna is fed to Fanna In the Litopenaeus culture pond, the bait of the prawns is supplemented, and the discharged high-transparency water can be discharged.

Implementation Effect:

The transparency, total nitrogen, total phosphorus, ammonia nitrogen and other indicators of the purified aquaculture discharge water reached the surface water Class III water standard. After 90 days of aquaculture, the yield of harvested prawns was 5.8kg/M2, and the cumulative harvest and feeding of cladocera was 53 kg. The whole breeding process is calculated according to the compound feed with a feed coefficient of 0.82.

According to the resource utilization method of Litopenaeus vannamei aquaculture wastewater of the present invention, the nitrogen and phosphorus nutrients in the wastewater are used in the process of purifying the eutrophic aquaculture wastewater by means of the food chain of microalgae-zooplankton-prawns At the same time, the recycling of nutrients such as nitrogen and phosphorus not only protects the aquaculture water environment, saves water resources, does not cause eutrophication pollution to the surrounding water environment, ensures the sustainable development of the aquaculture industry, but also supplements intensive shrimp farming. Natural bait is provided, the feed cost of prawn farming is reduced, and the breeding efficiency is improved. The method of the invention has relatively low input cost and strong technical operability.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the method of the present invention, some improvements and supplements can also be made, and these improvements and supplements should also be considered Be the protection scope of the present invention.

Claims (8)

1. a resource utilization method of intensive Litopenaeus vannamei culture waste water, it is characterized in that, described method comprises the following steps: Step S1: Filter the wastewater discharged from the intensive Litopenaeus vannamei culture pond with a slope filter screen; Step S2: collecting the waste water filtered by the slope filter screen in step S1 into the waste water storage tank; Step S3: transporting the waste water from the waste water storage tank in step S2 to the microalgae multiplication pond in the sunshine shed to cultivate microalgae; Step S4: Transport the cultivated algae water to the Cladocera or Copepod culture tank, and purify the microalgae in the water with the help of Cladocera or Copepod filter feeding to generate high-transparency water for recycling or discharge, and the generated branches Feeds for Litopenaeus vannamei culture are supplemented after horn or copepod harvest. 2. the resource utilization method of intensive Litopenaeus vannamei culture waste water according to claim 1, is characterized in that, the slope filter screen in the step S1 is made up of two parts, and the sieve mesh of the first part is 60-80 The mesh of the second part of the screen is 200 mesh, and the slope of the screen forms an angle of 30°-60° with the horizontal plane, which is adjusted according to the screen area, water flow and the number of suspended particles in the wastewater. Solid waste is automatically collected into the sewage tank under the action of water flow. 3. the resourceful utilization method of intensive Litopenaeus vannamei culture waste water according to claim 1, is characterized in that, the waste water filtered through the slope filter screen is transported in the waste water storage tank via pipeline, and the waste water storage tank is a cement pool or A mulched earthen pond covered with a plastic sheet to prevent other animals from entering the waste water storage tank. 4. the resource utilization method of intensive Litopenaeus vannamei culture waste water according to claim 1, is characterized in that, the container that microalgae is cultivated in the sunlight shed in step S3 can be photobioreactor, also can be simple and easy. Cement pool or removable sink. 5. the resource utilization method of intensive Litopenaeus vannamei culture waste water according to claim 1, is characterized in that, comprises the following steps in step S3: Step S31, the step of microalgae proliferation: microalgae proliferation needs to be pre-inoculated with beneficial microalgae with strong anti-pollution ability and high temperature resistance to directional control the types of microalgae that proliferate. Nannochloropsis oculata or Tetraselmis subcordiformis or Dunaliella salina, if the culture wastewater of Litopenaeus vannamei is fresh water, it can be inoculated with Chlamydomonasspp., Chlorella spp.), Scenedesmus spp., and Chlorococcum sp., microalgae need to be aerated continuously during the proliferation process, and the algae liquid can be transported to the cladocera or copepod culture tank after 3-5 days of cultivation . 6. the resource utilization method of intensive Litopenaeus vannamei culture wastewater according to claim 1, is characterized in that, when the culture wastewater of Litopenaeus vannamei has salinity, cultivate the species of water flea order (Calanoid) or Moinamongolica filter-feeds microalgae. When Litopenaeus vannamei aquaculture wastewater is fresh water, Daphnia magna or Daphnia carinata are cultured to filter-feed algae, and the culture process is continuously aerated. 7. the resource utilization method of intensive Litopenaeus vannamei culture waste water according to claim 1, is characterized in that, the volume ratio of the water body of microalgae proliferation and cladocera or copepod culture water body is at 2-3: 1. 8. the resource utilization method of intensive Litopenaeus vannamei culture waste water according to claim 1, is characterized in that, gathers siphon method with 100 mesh sieve silk bag collections every day from Cladocera or copepod culture pool For Cladocera or copepods, the daily harvest depends on the growth of the population and the density of algae cells in the water body.