With the continuous improvement of aquatic product quality and safety requirements and the continuous attention to the standardization of aquatic product sources, some problems in aquaculture have gradually begun to be exposed. Problem such as the degradation of aquaculture species, high aquaculture density, and arbitrary discharge of sewage and waste water have seriously affected the water environment of aquaculture waters, and also destroyed the regional ecological balance. Therefore, it is an effective way to solve the potential pollution hazards and make full use of wastewater resources to seek reasonable treatment technology and recycle the wastewater from factory aquaculture after treatment.
Then how should we treat wastewater from aquaculture plant? Let's take a look at the following methods:
1. Physical Filtration Method
The physical treatment method mainly includes filtration, separation, neutralization, precipitation, adsorption, etc. Its function is to remove large suspended solids and part of COD in aquaculture wastewater. Studies have shown that the removal rate of the total number of bacteria by the Ultrafiltraiton Membrane is higher than 90%, and the salt content of the aquaculture wastewater before and after treatment does not change, which meets the requirements for reuse in the aquaculture process. According to the results of the feasibility test, the process route for the reuse of aquaculture wastewater is: aquaculture wasterwater-first level sedimentation tank-clear water tank-o3 oxidizer-insulation tank-pretreatment system-fine filtration 1-UV radiation meter-ultrafiltration-fine filtration 2-nursery pond. This process route has undergone a fine filtration process before ultrafiltration to treat aquaculture wastewater to reduce membrane pollution, and the effluent quality is better.
Hongtek provides a series of microfiltration products, such as melt blown cartridges, string wound cartridges and Pleated Filter Cartridges, that are suitable for pre-filtration of aquaculture wastewater with high removal efficiency and simple operation.
2. Chemical Filtration Method
The chemical treatment method refers to the chemical reaction between chemicals and pollutants, so as to decompose and convert pollutants into non-toxic and harmless substances, or to inhibit the production of pollutants by chemicals as the main content. At this stage, the most frequently used chemical method at home and abroad is ozone treatment technology. Ozone can not only remove some toxic substances, but also has a good bactericidal effect. It can also inhibit the production of fish pathogenic microorganisms, oxidized organic matter, nitrogen elements and other harmful substances, and can reduce the content of suspended solids and COD in aquaculture wastewater.
3. Microbial Filtration Method
The principle of microbial filtration comes from soil self-purification, which is mainly used in in-situ remediation, and can deal with the problems of organic pollution and eutrophication of sediments. By studying beneficial microorganisms to improve aquaculture ecology and the growth-promoting effect of microbial decomposition on sediment and fish, it is concluded that microorganisms can decompose the polluted sediment of about 4cm at the bottom of the fish pond in about 30 days. Other studies have shown that fungal microorganisms can reduce COD content, nitrogen concentration and substrate sulfide in water. Moreover, microbial treatment does not cause disease in aquatic products.
After all, aquaculture wastewater treatment technology includes physical filtration treatment, chemical filtration treatment and biological filtration treatment, etc. Among the physical treatment technologies, microfiltration and membrane filtration have better effects; chemical treatment technology mainly relies on various chemicals; plant filtration, microbial filtration and animal filtration together constitute biological treatment technology. These methods can effectively remove suspended solids (SS), ammonia nitrogen, chemical oxygen demand(COD), biological oxygen demand(BOD) in wastewater, so as to meet the requirements of recycling or discharge standards.