Reaserch On Sulfate Organic Wastewater Treatment By Anaerobic Digestion

Anaerobic biological treatment of organic wastewater is the most competitive technology at present,which can produce capacity and energy saving.However,the anaerobic method in the treatment of high concentrations from organic wastewater rich in sulfate,due to the competition between SRB and the matrix of MPA,and the toxic inhibition of sulfate reducing products,which greatly affects the application of anaerobic treatment of high concentration organic wastewater containing sulfate.To solve this problem,the effect of different COD / SO₄^2-and HRT on the anaerobic digestion of sulfate organic wastewater was studied by using continuous stirring reactor system?CSTR?in the treatment of sulfuric acid organic wastewater under medium temperature condition,so as to provide theoretical basis for engineering application of anaerobic digestion of sulfate wastewater.?1?The COD/SO₄^2-ratio did not enhance the effect of anaerobic digestion of sulfate organic wastewater.When the COD/SO₄^2-ratio is 20,the accumulation of VFAs in the reactor increases due to the high loading of organic matter,which suppresses the methane production process in anaerobic fermentation.When the COD / SO₄^2-ratio decreased to 10,Although the inhibition caused by the accumulation of VFAs in the fermentation broth was alleviated,the gas production rate and methane content of the anaerobic digestion system were not improved;the degradation rate of organic matter,the removal rate of sulfate,the conversion rate of COD to methane,the utilization rate of MPA and the efficiency of energy conversion were decreased,COD removal rate was only 43.79%.However,the utilization rate of SRB in bacteria increased,and the rate of sulfate reduction was relatively stable,and remained at about 85.70%.?2?Shortening the hydraulic retention time?HRT?is beneficial to improve the anaerobic digestion effect of sulfate organic wastewater.When the HRT decreased from 12 d to 9d,the gas production rate and methane content of the anaerobic digestive system increased obviously,the methane content was more than 60%,and the accumulation of VFAs was not found in the fermentation broth.The degradation rate of organic matter,COD methanation rate,MPA on the utilization of electrons and energy conversion efficiency are relatively increased,while the sulfate removal rate and SBR on the utilization of electrons have decreased,but did not have a significant impact on the reduction of sulfate,SO₄^2-removal rate is also maintained at 80% or more.?3?The effect of changing OLR on gas production rate,COD removal rate and methane content was significant.