两种典型污泥热解特性及动力学机理

Pyrolysis Characteristics and Kinetics Mechanism of Two Typical Sludge

选取具有代表性的石化污泥和市政污泥,在热天平上对不同含水率、不同升温速率下的两种污泥进行热解实验,并对两种污泥的热解特性作了比较分析.结果发现:随升温速率增大出现热滞后现象,含水率不同对污泥不同热解阶段影响不同.根据热解TG曲线和DTG曲线分别求出了两种污泥的挥发分综合释放特性指数D,发现石化污泥挥发性好于市政污泥.最后,通过建立污泥热解动力学模型,采用Coats-Redfem积分法对两种污泥的热解动力学参数进行了求解分析.从热解动力学参数以及实验结果分析表明,污泥中含水率为25%时,具有较好的热解特性.

Petrochemical sludge and municipal sludge, as two kinds of representative sludge, were selected in this paper. The pyrolysis experiment of these two kinds of sludge with different moisture content and heating rate was conducted on thermobalanee, and their pyrolysis characteristics were compared. In the experiment, with the increase of heating rate, the thermal inertia occurred, and different moisture content exerted different impact on sludge at differ- ent stage. Index D, the volatile release complex characteristic, was calculated through the TG and DTG curves of pyrolysis. According to the index D, the volatile release characteristic of petrochemical sludge was superior to that of municipal sludge. The pyrolysis kinetic parameters of these two kinds of sludge were obtained via the establishment of the kinetics model and the integral method of Coats-Redfem. According to the pyrolysis kinetic parameters and the pyrolysis experimental result analysis, the pyrolysis characteristics of sludge with 25 percent moisture were best.