Breeding wastewater purifying method

Abstract

The invention provides a breeding wastewater purifying method. The method comprises the following steps: 1) fermenting pig manure discharged from pigpens in a biogas digester for 15 days to one month, and standing still for layering to obtain biogas residues at the bottom and biogas residue water at the top; and carrying out static settlement on breeding wastewater to obtain biogas residues at the bottom and drying the biogas residues; and 2) discharging the biogas residue water into a pond, a lake or a reservoir, planting rice and / or vegetables on the surface of water and breeding fish in water. According to the method, based on a floating plate planting technique, hydrophilous plants are transplanted into lakes and ponds from farm land and therefore dual effects of increasing income and preventing water pollution can be achieved. By planting vegetables on the surface of water, the ammonia nitrogen content can be reduced by 60%-85%, the total nitrogen content is reduced by 40%-75%, the total phosphorus content is reduced by 30%-60%, the sodium content is reduced by 8%-12% and the potassium content is reduced by 30-40%; the occurrence rate of plant diseases and insect pests of vegetables planted on the surface of water is much lower than the occurrence rate of vegetables planted in farm land; the vegetables planted on the surface of water are completely prevented from use of chemical fertilizers and pesticides.

Description

technical field [0001] The invention belongs to the technical field of wastewater treatment, and in particular relates to a method for purifying aquaculture sewage. Background technique [0002] my country's national meat production in 2008 reached 72.787 million tons. However, while large-scale breeding meets the needs of urban and rural people, the current management mode also causes the unfavorable situation of excessive livestock and poultry excrement and excessive flushing water. The resulting increasingly serious environmental pollution problems not only affect economic development, but also endanger ecological security. The chemical oxygen demand (COD) of livestock and poultry manure produced by agricultural production far exceeds the sum of COD emissions of industrial wastewater and domestic sewage in my country. Poultry breeding pollution has become the third largest pollution source after industrial pollution and domestic pollution, and has become one of the main ...

AI Technical Summary

Problems solved by technology

At the same time, the volume of livestock and poultry wastewater fluctuates greatly, the slag content, organic matter and nitrogen and phosphorus concentrations are high, the treatment technology is not mature enough, and the management and operation costs are high

At present, many large-scale farms in my country have carried out the treatment of livestock and poultry breeding wastewater, but most of the wastewater treatment effluent quality of large-scale farms has not yet reached the national first-level discharge standards, far less than half of the industrial wastewater treatment compliance rate

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