【摘要】 基于煤粉具有疏水性能强、热值高等特点,采用真空抽滤脱水实验法考察了煤粉投加量、粒度对污泥调质与机械脱水效果的影响。通过测试污泥调质前后的比阻及其分子结构,初步探讨了基于煤粉的污泥调质与机械脱水的机理。结果表明:当煤粉粒度为150~425μm、煤粉投加量为2.5 g/100 m L污泥时,污泥经机械脱水后滤饼含水率由调质前的75.22%降至56.60%,抽滤时间从调质前的300 s降至120 s,污泥比阻值从调质前的2.65×106s2/g降至6.37×105s2/g,污泥热值从调质前的8.04 MJ/kg提高至17.92 MJ/kg;煤粉改善污泥机械脱水性能的机理主要表现在煤粉能显著降低污泥比阻并增强污泥疏水性能。可见,基于煤粉的污泥调质不仅能显著地改善污泥的机械脱水性能,还能提高污泥的热值,为污泥的能源化利用创造了条件。更多还原

【Abstract】 Since coal has special characteristics such as strong hydrophobicity, high calorific value, it was used for sludge conditioning in order to mechanical dewater from the sludge. The influences of adding amount and size distribution of coal on the promoting effect were investigated by vacuum extraction filtering method. Mechanism of sludge conditioning and mechanical dewatering in the case of addition of coal was preliminarily discussed based on the results of specific resistance(SRF) and molecular structure of sludge with or without conditioning. The results indicated that when the particle size distribution of coal was from 150 to 425 μm and the adding amount was 2.5 g/100 m L sludge, total moisture content of the filter cake was reduced from 75.22% to 56.60%. The suction time was reduced from 300 s to 120 s, and SRF was reduced from 2.65 ×106s2/g to 6.37 ×105s2/g. The calorific value was obviously promoted from 8.04 MJ/kg to 17.92 MJ/kg. These promoting effects should be attributed to the reduced SRF and enhanced hydrophobic properties of sludge due to the addition of coal. Consequently, sludge conditioning by using coal can not only significantly improve the mechanical dewatering prosperities of the sludge, but also improve the calorific value, which can save the energy during the utilization of sludge.更多还原