污泥固化的试验研究

为研究一种经济有效的途径将污泥单独填埋，以石灰、土和粉煤灰为固化材料，研究了不同配合比下固化污泥的工程性质．通过渗透性试验和强度试验，发现采用适当的配合比，渗透性有很大提高，固化污泥的强度随着时间的推移而增长，可以满足填埋的要求；采用冷冻干燥技术和扫描电镜研究了固化污泥的微观结构，发现固化后污泥的密实性有较大提高，这是其强度提高的一个重要原因；应用分彤几何的理论，对由扫描电镜获取的固化污泥微观结构图像进行了定量分析，结果表明分形雏数和强度之间有较强的正相关性。

Test on Methods to Solidify Wastewater Sludge

To develop an effective and economic method for monofilling, tests were conducted to study the feasibility of fly ash, lime, and silty clay (at various mixing ratios) in sludge solidification. Variable head permeability test, torsional vane shear tester and pocket penetrometer were utilized to study engineering properties of the solidified sludge. It was revealed that the strength of the solidified sludge increased with the time and the decrement of moisture content. Significant increases in strength and permeability made it suitable for monofilling. Freeze-drying technology and scanning electron microscope ( SEM ) were adopted to study the microstruc-ture of the solidified sludge. It was found that compactness of sludge was improved after solidification, which was an important reason for strength increase. Based on theory of fractal geometry, quantitative analysis was carried out on the SEM images. The analysis revealed a considerable positive correlation between fractal dimension and strength.