A Study On The Surplus Sludge Treated By Autothermal Thermophilic Aerobic Digestion

The autothermal thermophilic aerobic digestion process is one kind of sludge stabilization and reduction technology has been most discussed and emphasized in the recent years, under aerobic conditions, microorganism cerate exothermal by their own reaction, partly are used to supplement the system energy consumption, others are used to rise the reaction temperature, in order to come to the purpose of thermophilic aerobic digestion. Cells could be dissolved under the high-temperature, and sludge can be sterilized which reduced the number of parasites. This subject sum up the research results of international and domestic in term of the relevant areas of aerobic digestion technology on the basis a lot of study and investigation, from a new perspective analyzed the factors that affect the digestion results of the autothermal thermophilic aerobic digestion process.Experiment adopt the autothermal thermophilic aerobic digestion (ATAD) reactor designed by our own, using the dewatered sludge of Xi'an Beishiqiao wastewater treatment center, with intermittent reaction mode, in terms of changing the operating parameters, through continuous monitoring index of sludge VSS, soil temperature Ph value in different working condition, total phosphorus, determining optimized operating parameters of the system, it is:while the sludge concentration was 5%～8%, the aeration was 0.4-0.8L/min, stirring strength was 120r/min, soil temperature increased to 48℃, VSS removal rate reach to 40.2%, DHA decline rate reached to 94.3%, achieving effective disinfection, making sludge stability, but it could bring up the dehydration property of sludge come to worse. Under the optimum running condition, through monitoring the changes of DHA, COD, studied the autothermal thermophilic aerobic digestion process influence on sludge stability and disinfection; through analyzing variation of sludge specific resistance, studied the effects of dewaterability with aerobic digestion process. through analyzing the variation synchronism of TOC, total phosphorus, total nitrogen, ammonia nitrogen, studied the reason of happening of cytolysis; through monitoring the extracellular polymeric substance(EPS), and compared with variation of sludge specific resistance, studied the cytolysis influence on dewaterability; through analyzing variation of TOC combined with extracellular polymeric substance, studied the relationship between cytolysis and changes of protein content; through a contrastive study of variation relationship of EPS and DHA, discussed biology recombination in ATAD systems.