Research On The Microwave-modified Activated Carbon Fiber Treatment Of Residual Sludge And Its Effect On Sludge Anaerobic Digestion

As life sewage and wastewater treatment depth increasing,the sewage treatment plant sludge produced more and more,anaerobic digestion as well as can realize sludge reduction,stabilization and recycling technology,has attracted much attention in recent years.Sludge is hydrolyzed in the process of anaerobic digestion,and the sludge is pretreated before anaerobic digestion.Microwave pretreatment is one of the many pretreatment method,the efficiency of microwave pretreatment on the sludge flocs burst alone is limited,the absorbing material is added to into the mud,can improve the efficiency of sludge on the use of microwave energy,but add the process of absorbing material pretreatment material antioxidant properties limited and easy adhesion,and sludge pretreatment efficiency remains limited.Currently,the commonly used absorbent materials for microwave pretreatment are Activated Carbon Fiber(ACF).In this paper,Modified Activated Carbon Fiber(MACF)is added to the sludge to improve the pretreatment of sludge.This paper analyzes the effects of microwave method on sludge pretreatment and the performance of the sludge anaerobic digestion after pre-treatment.The changes of microbial population in sludge anaerobic digestion were discussed.The main conclusions are as follows:(1)During microwave pretreatment,the optimum amount of material and the best pretreatment time were 0.16 g/gVS and 4min.At this point the MACF-microwave pretreatment SCOD,polysaccharide and protein concentration in the sludge,the largest respectively 2058,382 and 200 mg/L,increased by 31.08%,31.08% and 73.6% than microwave pretreatment separately(2)Under the optimum pretreatment conditions,the sludge with anaerobic digestion was the biggest change of the sludge with the MACF-microwave method.Protein,polysaccharide and DNA concentration were reduced from 382,200 and 37.36 mg/L to 86,90.8 and 13.12 mg/L respectively,decreased by 77.3%,54.6% and 64.88% respectively.The SCOD concentration increased from 2078 to 2722mg/L,increasing by 30.99%,and then to 835mg/L,down 69.32%.The concentrations of nitrogen and ammonia were increased by 233 and 35mg/L to 454 and 338mg/L respectively.(3)Anaerobic digestion process of adding the total volume of the modified activated carbon fiber pretreatment of sludge is higher than other groups,the total volume is 737 ml,400 ml sludge of a total of 389 ml of methane,the methane content of 52.78% on average.The amount of VFA in the sludge that was pretreated by the MACF-microwave method was the largest.Without pretreatment,microwave pretreatment,add ACF microwave pretreatment and add MACF microwave pretreatment sludge,the biggest VFA accumulation were 455.24,526.50,365.69 and 805.11 mg/L,the highest content of acetic acid,propionic acid.(4)After pretreatment for sludge anaerobic digestion,add MACF microwave pretreatment in the sludge microbial population diversity and uniformity is best.A substantial reduction in deformation of bacteria in the sludge after pretreatment,Aminicenantes content is the highest,after the pretreatment of anaerobic digestion sludge can detect hydrogen production of Syntrophomonas and Syntrophobacter.