不同级配垃圾焚烧底渣固化市政污泥工程特性分析

开展了（炉排炉和流化床炉）两种垃圾焚烧底渣与固化剂共同作用下固化市政污泥的工程特性研究。分析了两种底渣化学成份及物理级配上的差异，重点考察了在密封养护情况下，测定了不同底渣固化体的含水率、pH值、无侧限抗压强度及28d渗透系数等工程特性指标。研究结果表明：相同含量的两种底渣固化体含水率及pH相同，且含水率随底渣含量增加而降低，而pH值随底渣含量增加而增加；随着底渣含量增加，级配良好的炉排炉底渣固化体强度比级配不良的流化床底渣固化体强度从高8 kPa增加到30 kPa；受底渣级配的影响，炉排炉底渣固化体渗透系数随底渣含量增加而增大，而流化床底渣固化体渗透系数基本不变。级配良好的炉排炉底渣固化体工程特性优于级配不良的流化床底渣固化体，具有更强的骨架作用。研究成果为污泥及垃圾焚烧底渣填埋处置提供了科学借鉴。

Engineering characteristics analysis of sewage sludge solidified by different gradations municipal solid waste incineration bottom ash

In this study, an inorganic curing agent was added to two different types of municipal solid waste incineration (MSWI) bottom ash, grate type incinerator and fluidized bed incinerator bottom ash, in order to treat municipal sludge. The differences in the chemical compositions and particle size distribution between the two types of bottom ash were analyzed. In particular, engineering indices, such as water content, pH, unconfined compressive strength, and the coefficient permeability of the solidified body after 28 days of sealed curing, were tested. The results showed that the two types of solid matrix with the same content of bottom ash had the same water content and pH, and the water content of the solid matrix decreased and the pH increased with an increase in the content of MSWI bottom ash. The unconfined compressive strength of the solidified body with the grate furnace bottom ash, which had a good gradation, was greater than that of the solidified body with circulating fluid bed (CFB) bottom ash. It increased from 8 kPa to 30 kPa with increasing bottom ash content. The coefficient permeability of the solidified body with grate furnace bottom ash increased with an increase in the content of bottom ash. However, the coefficient permeability of the solidified body with CFB bottom ash was almost constant, which was caused by the particle size distribution of the bottom ash. Due to good gradation, the engineering characteristics of sewage sludge solidified by grate furnace bottom ash was better than that of CFB bottom ash, and sewage sludge solidified by grate furnace bottom ash had a stronger skeleton effect. This research provides an insight into landfill sludge and MSWI bottom ash.