Research On Construction Of Microbial Deep Dehydration System And Sulfur Deposition

As the pace of urbanization construction continues to accelerate,the city scale and population density continue to increase,resulting in a rapid increase in urban sewage production and treatment scale.As an inevitable by-product of the sewage treatment process,the output of surplus sludge is also increasing.In China,the problem of "heavy water and light mud" has always existed.In recent years,compared with sludge treatment facilities,sewage treatment facilities have been continuously developed and improved.China’s sewage treatment rate is much higher than that of sludge.At present,some large cities have seen sludge besieged cities.The remaining sludge has the characteristics of high water content,high organic matter,a large number of eggs and viruses,etc.If it is not handled properly,it will easily cause secondary pollution.Sludge treatment and disposal often has high requirements for the sludge moisture content.It is necessary to explore a deep dehydration pretreatment technology for sludge.Taking the sludge in a concentrated pond of a sewage treatment plant in Longhu Town,Zhengzhou City as the research object,Thiobacillus thiooxidans and Thiobacillus ferrooxidans were screened from the sludge.In about 24 days,a single Thiobacillus thiooxidans can be inoculated with acidified sludge to complete the construction of a microbial deep dehydration system.In about 36 days,the construction of a mixed strain microorganism dehydration system can be completed.Using a single Thiobacillus ferrooxidans for domestication of sludge,the p H value of the sludge system can be reduced to about 2.8 at the lowest,and acidified bacteria could not be obtained to complete the construction of the microbial deep dehydration system.Biological leaching experiments with different strains: using a single Thiobacillus thiooxidans acclimated sludge for inoculation,when the sulfur powder was added at a concentration of 2 g/L and the inoculation ratio was 5%,the best sludge dewatering performance was CST and SRF,respectively,44.6 s,2.92×1012 m/kg,decreased by 55% and 49% respectively.When using mixed strains to acclimate sludge,the concentration of sulfur powder is 2 g/L,the concentration of Fe2+ is more than 4 g/L,and the inoculation ratio is 20%.After 24 hours of leaching,the p H value is 2.57.The sludge dewatering performance is the best.The best CST and SRF were 40.2 s and 1.39×1012 m/kg,respectively,which were reduced by 60% and 76%,respectively.The sludge dewatering performance was significantly improved.In this paper,a slow-release material prepared by mixing PVA and sulfur powder is used instead of elemental sulfur powder for biological leaching to explore the solution to the problem of sulfur powder deposition.The experiment found that the sulfur powder utilization rate and leaching effect did not improve,but the leaching effect could reach more than 95% of the optimal working conditions of the experimental group directly added sulfur powder.The sulphur powder slow-release material has the same physical and chemical properties after leaching and can be reused.It is conjectured that the sulphur powder slow-release material can be made into a filling material.The biological leaching experiment is completed by the inflow and discharge of sludge,and the filling material is replaced by Solve the problem of sulfur powder deposition in sludge.