3种因素影响下固化废弃淤泥的微观特性研究

为揭示初始含水率、固化剂掺量和龄期3种因素对固化废弃淤泥力学性质影响的本质，以硫氧镁水泥固化废弃淤泥为研究对象，开展了不同含水率（w）、固化剂掺量（W_g）和龄期（T）条件下固化淤泥的电镜扫描试验，利用图像处理软件研究了固化淤泥的微观接触面积率（R_CA）、平均丰度（C_m）和分形维数（D）受含水率、固化剂掺量和龄期的影响规律。结果发现:含水率的增加会抑制硫氧镁水泥的水化，增加固化淤泥结构的分散性，进而减小固化淤泥的接触面积率、平均丰度，提高其分形维数。而固化剂掺量和龄期有利于固化反应的发展，促进扁圆状固化产物的生成，提高固化淤泥结构的紧密性，从而增加固化淤泥的接触面积率、平均丰度，降低其分形维数。3种因素中，龄期对固化淤泥的接触面积率和分形维数影响最为显著。

Research on the micro-characteristics of solidified waste sludge under the effect of three factors

To essentially investigate the effect-mechanism of water contents (w), curing agent dosages (W_g) and ages (T) on the mechanical behavior of stabilized waste sludge, a series of Scanning Electron Microscope (SEM) tests under different w, W_g and T are conducted by taking the waste sludge solidified by magnesium oxysulfate cement as the research object. The effects of w, W_g and T on the micro-parameters of the stabilized sludge such as contact area ratio (R_CA), average abundance (C_m) and fractal dimension (D) are addressed by using the Image Pro Plus. The results show that the increase in w will prevent the hydration of magnesium oxysulfate cement and enhance the dispersibility of the microstructure of the stabilized sludge, further decrease the values of R_CA and C_m and improve the value of D. Among the aforementioned three factors, T has a significant influence on the development of R_CA and D, and W_g plays an important role in the evolution of C_m.