氧化亚铁硫杆菌与硫酸改善城市污泥的脱水性能

Study on Municipal Sewage Sludge Dewaterability Improved by Acidithiobacillus Ferrooxidans and Sulfuric Acid

研究生物酸化和化学酸化调理法对污泥脱水性能的影响,以污泥比阻作为污泥脱水性能的评价指标.结果表明,生物酸化调理污泥的脱水效果和稳定性均优于化学酸化.在接种氧化亚铁硫杆菌菌液为10%时,可使原泥脱水效率提高49.7%;而酸处理的最佳条件为初始pH 3.2,此时污泥脱水性能较原泥提高30.8%.比较调理过程中污泥体系pH的变化发现,当接种量一定,生物调理法可较长时间维持利于脱水的酸性环境.经电镜扫描可见,生物法调理的污泥含硫杆菌,其团形均匀、孔隙度大、泥质松软.红外光谱分析表明,氧化亚铁硫杆菌通过酶作用把胞外聚合物中的蛋白质分解,从而改善污泥脱水性能.

The study was performed on effects of biological acidification and acid treatment on the sludge's dewaterability. Specific resistance to filtration(SRF) was used to evaluate the dewatering properties. Experimental results showed that the dewaterability and stability of sludge treated by biological acidification were better than chemical acidification. With 10% inoculation of Acidithiobacillus ferrooxidans bacteria liquid,the dewaterability of original sludge had been impoved by 49.7%,compared with the 30.8% of acid treatment of initial pH 3.2. The sludge systems' pH varaiation were compared during conditioning process,it was found that biological conditioning method at a certain inoculation can maintain longer acidic environment in favor of dehydration. By electron microscope scanning(SEM),the sludge shape of bioleaching treatment was uniform,large porosity,soft texture,and the bacteria strains were observed. Infrared spectrum results showed that,Acidithiobacillus ferrooxidans decomposed protein of extracellular polymeric substances(EPS) through enzyme action,improving sludge dewatering performance.