Livestock and poultry farm sewage mainly includes urine, part of the excrement and flushing water, is a high concentration of organic sewage, and suspended matter and ammonia nitrogen content. Our company has a complete treatment process system, which reduces the concentration of COD and BOD through anaerobic reaction, and then reduces the concentration of nitrogen and phosphorus through effective denitrification and dephosphorization process, so as to achieve safe discharge.
Hazards to the environment caused by sewage from livestock and poultry breeding:
With the rapid development of China's animal husbandry, livestock farming scale is more and more big, the large-scale farms every large amount of discharge of wastewater and concentration, and the wastewater contains a lot of pollutants, belongs to the high concentration organic wastewater, rich in a large number of pathogens directly discharged into water body or disposition point is not appropriate, the rain flush into the water, may cause serious deterioration of surface water and groundwater quality. For example, heavy metals, residual veterinary drugs and a large number of pathogens, if discharged into the environment without treatment or directly for agricultural use, will cause serious pollution to the local ecological environment and farmland.
Introduction to sewage Treatment technology of livestock and poultry farms:
At present, there are many anaerobic processes used to treat livestock and poultry farm wastewater in China, among which the following are more commonly used: anaerobic filter (AF), up-flow anaerobic sludge bed (UASB), compound anaerobic reactor (UASB+AF), two-stage anaerobic digestion and up-flow sludge bed reactor (USR), etc.
Livestock and poultry industry sewage treatment method: Aerobic treatment refers to the use of aerobic microorganisms to treat aquaculture wastewater a process. Aerobic biological treatment can be divided into two categories: natural aerobic treatment and artificial aerobic treatment.
Natural aerobic biological treatment is a method of purifying wastewater by using natural microorganisms in water and soil. It is also called natural biological treatment method. There are mainly two kinds of water purification and soil purification. The former mainly includes oxidation pond (aerobic pond, facultative pond, anaerobic pond) and breeding pond, etc. The latter mainly has the land treatment (the slow speed filtration, the fast method filtration, the ground diffuse current) and the artificial wetland and so on. The natural biological treatment method not only has low cost of infrastructure and less power consumption, but also has a higher removal rate of refractory organic matter, nitrogen, phosphorus and other nutrients and bacteria than the conventional secondary treatment, and some of them can achieve the effect of tertiary treatment. In addition, under certain conditions, this method can be combined with sewage irrigation to realize the utilization of sewage resources. The disadvantages of this method are the large floor area and the seasonal effect. However, if the farm scale is small and there are abandoned ditches, ponds and tidal flats nearby for use, the method should be chosen as far as possible to save investment and treatment costs.
Artificial aerobic biological treatment is a wastewater treatment method that uses artificial enhancement of oxygen supply to improve aerobic microbial activity. The methods mainly include activated sludge process, biological filter tank, biological rotary plate, biological contact oxidation method, sequencing batch activated sludge process (SBR), anaerobic/aerobic process (A/O) and oxidation ditch method. In terms of treatment effect, the treatment effect of contact oxidation method and biological turntable is better than that of activated sludge method. Although the treatment effect of biological filter is also very good, it is easy to cause filter clog. Oxidation ditch, SBR and A/O processes are all improved activated sludge processes. The effluent from oxidation ditch has good water quality and less sludge, and can also be denitrified, but the BOD load of its treatment is small, covers an area of large, and the operation cost is high. SBR method has a high degree of automatic control and can conduct deep treatment of sewage, but its disadvantages are small BOD load and large one-time investment. A/O body is an activated sludge treatment process with dual functions of BOD removal and denitrification. Although its investment is relatively large, the water treated by this method is easy to discharge to the standard. Therefore, A/O method can be used for farms with large scale, large amount of waste water production and strong economic capacity, while aerobic treatment technologies such as contact oxidation and biological rotary table can be used for farms with medium scale.