Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University , Nanjing , People's Republic of China.
Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization , Nanjing , People's Republic of China.
Environ Technol. 2019 Oct;40(24):3176-3189. doi: 10.1080/09593330.2018.1465129. Epub 2018 Apr 22.
Prior to mechanical dewatering, sludge conditioning is indispensable to reduce the difficulty of sludge treatment and disposal. The effect of bioacidification conditioning driven by LX5 on the dewatering rate and extent of sewage sludge during compression dewatering process was investigated in this study. The results showed that the bioacidification of sludge driven by LX5 simultaneously improved both the sludge dewatering rate and extent, which was not attained by physical/chemical conditioning approaches, including ultrasonication, microwave, freezing/thawing, or by adding the chemical conditioner cationic polyacrylamide (CPAM). During the bioacidification of sludge, the decrease in sludge pH induced the damage of sludge microbial cell structures, which enhanced the dewatering extent of sludge, and the added Fe and the subsequent bio-oxidized Fe effectively flocculated the damaged sludge flocs to improve the sludge dewatering rate. In the compression dewatering process consisting of filtration and expression stages, high removal of moisture and a short dewatering time were achieved during the filtration stage and the expression kinetics were also improved because of the high elasticity of sludge cake and the rapid creeping of the aggregates within the sludge cake. In addition, the usefulness of bioacidification driven by LX5 in improving the compression dewatering of sewage sludge could not be attained by the chemical treatment of sludge through pH modification and Fe addition. Therefore, the bioacidification of sludge driven by LX5 is an effective conditioning method to simultaneously improve the rate and extent of compression dewatering of sewage sludge.
在机械脱水之前，污泥调理对于降低污泥处理和处置的难度是必不可少的。本研究考察了生物酸化调理剂 LX5 对压缩脱水过程中污水污泥脱水率和程度的影响。结果表明，LX5 驱动的污泥生物酸化同时提高了污泥的脱水率和程度，这是物理/化学调理方法（包括超声、微波、冷冻/解冻或添加化学调理剂阳离子聚丙烯酰胺 (CPAM））无法达到的。在污泥生物酸化过程中，污泥 pH 值的降低导致污泥微生物细胞结构的破坏，从而提高了污泥的脱水程度，而添加的 Fe 和随后的生物氧化 Fe 有效地絮凝了被破坏的污泥絮体，从而提高了污泥的脱水率。在过滤和挤压阶段组成的压缩脱水过程中，在过滤阶段实现了高水分去除和短脱水时间，并且由于污泥饼的高弹性和污泥饼内的聚集体的快速蠕动，挤压动力学也得到了改善。此外，通过 pH 值调节和 Fe 添加进行化学处理污泥不能实现 LX5 驱动的生物酸化对污水污泥压缩脱水的改善效果。因此，LX5 驱动的污泥生物酸化是一种有效改善污水污泥压缩脱水速率和程度的调理方法。
