低温热水解对污泥触变性及脱水性能的影响

污泥经过热水解预处理后，其流变和理化性质发生了不可逆的变化。为实现后续污泥处理处置过程的最优化，分别采用触变动力学系数(K)和离心脱水泥饼的总固体含量(TS)作为污泥触变性及脱水性能的评价指标，系统研究低温热水解(60~90 ℃)对于污泥触变性及脱水性的影响。结果表明，热水解48 h后，污泥的触变性增大，脱水性能提高，且热水解温度的升高与触变性的增大和脱水性能的提高呈对数关系。污泥脱水性的提高与触变性的增强呈良好的线性关系，触变动力学系数有望成为比较污泥脱水性能的新工具，从流变学角度提出了评价污泥脱水性能的新方法。

Effect of low-temperature thermal hydrolysis on sludge thixotropy and dewaterability

When sludge was subjected to thermal hydrolysis, an irreversible change occurred on its rheological and physicochemical properties. To optimize the subsequent sludge treatment and disposal process, the effect of low-temperature thermal hydrolysis (60~90 ℃) on its thixotropy and dewaterability was systematically investigated when the thixotropic kinetic coefficient (K) and the total solids (TS) of the centrifugal dewatered cake were taken as the evaluation indicator of sludge thixotropy and dewaterability, respectively. Experimental results show that sludge thixotropy and dewaterability increased after 48 h thermal hydrolysis, the logarithmic increase correlations were observed between heating temperature and thixotropy or dewaterability. Moreover, sludge dewaterability increase due to thermal treatment was logarithmically proportional to its thixotropy increase. This indicates that K could become a reliable tool to compare sludge dewaterability, and provide a new method to evaluate sludge dewaterability from a rheological perspective.