The wastewater from aquaculture farms generally contains eutrophication substances such as N and P, as well as heavy metals such as copper, arsenic, mercury, and selenium;
Residues of veterinary drugs such as antibiotics and antioxidants; Escherichia coli and other zoonotic infectious disease pathogens.
Among them, the pollution load is relatively high, including COD, BOD, NH3-N, and SS, which belong to the category of high COD, high ammonia nitrogen, and high SS wastewater.
Moreover, Wastewater has a certain degree of corrosiveness and high phosphorus content, and pig hair, coarse fibers, etc. can easily cause damage or blockage, leading to system paralysis.
1. Removal of nitrogen from wastewater
The organic nitrogen in aquaculture wastewater is initially decomposed into inorganic nitrogen by microorganisms, and therefore needs to be removed. The comprehensive utilization of fast and slow filters in aquaculture wastewater treatment systems creates conditions for nitrification.
2. Removal of Phosphorus from Wastewater
Phosphorus removal is divided into three steps:
One is to remove phosphorus through the adsorption of coarse sand, gravel and other fillers in fast filter, artificial wetland system and slow filter, as well as the chemical reaction between fillers and phosphate ions;
The second is to remove microorganisms from the system through normal assimilation and absorption in fast and slow filters and artificial wetland systems, as well as regular cleaning or replacement of fillers;
Thirdly, inorganic phosphorus in aquaculture wastewater is absorbed and assimilated by plants such as reeds, water bamboo, and water hyacinth in the artificial wetland system, and removed through regular harvesting of plants;
The wastewater from aquaculture farms contains Wastewater, waste residue, and foul odor. If not treated, it will cause serious environmental pollution.
