超声波-游离亚硝酸联合预处理污泥强化厌氧消化的机制解析OA北大核心

In this study,the effects of ultrasonic(US)pretreatment,free nitrous acid(FNA)pretreatment and ultrasonic-freenitrous acid(US-FNA)combined pretreatment on many aspects of sludge,including the dissolution of organic matter,dispersion of flocs,release of cel-lular contents,and methanogenic performance.The results showed that the primary impact of ultrasonic pretreatment was the dispersion of flocs and the dissolution of extracellular polymeric substances,whereas the pretreatment with free nitrous acid resulted in the release of cell content.In comparison to the no-treatment control,the generation of sludge methane exhibited a significant increase of 37.1％.Specifical-ly,the ultrasonic group demonstrated a 1.07-fold increase,while the free nitrous acid group had a 1.08-fold rise.Nevertheless,the com-bined pretreatment of ultrasonic and free nitrous acid exhibited distinct roles,and no apparent synergistic impact was seen.The incorporation of free nitrous acid had the potential to decrease the rate of gas generation during the initial phase of anaerobic digestion of sludge.However,it did not exert a substantial impact on the overall gas output over time.The examination of microbial flora in sludge following fermentation re-vealed that the presence of free nitrous acid had a significant influence on the variety of microorganisms in the sludge.