脱水污泥力学性能研究及其对料仓的影响分析

MECHANICAL PROPERTIES OF DEWATERED SEWAGE SLUDGE AND ITS INFLUENCE ON THE STORAGE BIN

采用土工试验,对污泥的孔隙比、压缩系数、应力位移关系、抗剪强度与垂直压力之间的关系等进行了研究,简要分析了污泥性能对料仓的影响.结果表明,污泥的含水率、孔隙比明显高于一般的淤泥质土.结实污泥的抗剪强度、内聚力都明显高于松散污泥.松散污泥具有高压缩性,在垂直压力62.5～100kPa附近出现压缩系数的极小值,污泥颗粒结构相对稳定,在垂直压力大于60kPa,超固结现象明显,其内摩擦角与结实污泥接近.污泥进入料仓前应先将污泥进行破碎,避免污泥的超固结现象发生.

Because of the lack of the research of the mechanical properties of the dewatered sewage sludge, this paper carried out geotechnical experiments, to study the relationship among the void ratio, the compressibility coefficient, the stress-strain relation, the shearing strength and the vertical pressure, and to analyze the influence of the properties of the sludge on the storage bin. Results show that the water ratio and the void ratio of the sludge are much higher than those of the average mucky sludge. For the solid sludge, the shearing strength and the cohesion are much higher than those of the loose sludge. The loose sludge has a high compression, with a minimum compression coefficient under a vertical pressure around 62.5N100kPa, and the particle structure of the sludge is relatively stable. When the vertical pressure exceeds 60 kPa, the sludge is apparently over-consolidated, the internal friction angle is close to that of the solid sludge. Before putting the sludge into the bunker, it should be crushed to avoid to be over-consolidated.