3种因素影响下固化废弃淤泥的微观特性研究

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

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。

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,Wg 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 RCA 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).