盐度强化剩余污泥碱性发酵产酸

短链脂肪酸(SCFAs)是生物脱氮除磷的优质碳源,为提高剩余污泥碱性发酵SCFAs的产量,分别在20℃和35℃条件下,考察了不同盐度(0~25g/L)对剩余污泥碱性(pH=10)发酵的影响.结果表明:在20℃和35℃条件下,投加适量的氯化钠均可提高SCFAs产量,且氯化钠投加量为15g/L时SCFAs产量最大,较不投加时分别提高了42.3%和15.0%.进一步的研究表明,适量的投加氯化钠促进了生成SCFAs所需底物(蛋白质和多糖)的释放,同时提高了发酵系统的C/N(SCFAs/NH4+-N).因此,盐度联合碱性pH值可强化剩余污泥发酵产生SCFAs,同时达到剩余污泥减量的效果.

Enhanced production of short-chain fatty acids from waste activated sludge alkaline fermentation: The effect of sa-linity

Short chain fatty acids (SCFAs) were used as high quality carbon source for biological denitrification and phosphorus removal process. In order to improve the SCFAs production of waste activated sludge (WAS) in alkaline fermentation system, the effect of salinity (0~25g/L) on the WAS alkaline fermentation (pH=10) was studied at 20℃ and 35℃,respectively. The results showed that adding appropriate sodium chloride (NaCl) enhanced the SCFAs production. The highest accumulation of SCFAs appeared at 15g/L NaCl and improved by 42.3% (20℃) and 15.0% (35℃) comparing with no NaCl addition. Further researches indicated that adding NaCl could increase the release of substrate (protein and polysaccharide) to produce more SCFAs, accompanied by the increase of C/N (SCFAs/NH4+-N). Therefore, the integrated control of salinity and pH could enhance the SCFAs generation from WAS fermentation and promote WAS reduction simultaneously.