城市污水厂石灰干化污泥对水泥易烧性的影响

Effect of lime drying municipal sludge on burnability of cement clinker

针对城市污水处理厂污泥含水率高、体积大、泥质成分复杂且易造成二次污染的特点,采用石灰干化后利用水泥工业协同处置是其实现资源化的途径之一。实验结果表明,在煅烧温度1 400℃、保温时间60 min的条件下,掺加适量的石灰干化污泥有利于提高水泥生料的易烧性,熟料中f-Ca O含量符合国家标准;掺加质量比为12%的石灰干化污泥煅烧所得熟料与空白参比熟料的物相组成基本相同,当石灰干化污泥掺量过大时应根据泥质成分对生料配比进行相应的调整,以确保熟料达到水泥生产的质量要求。研究成果可为水泥工业协同处置城市污泥提供借鉴与技术参考。

Municipal sludge was in high moisture content, large volume, complex components and easy to cause the secondary pollution. The utilization of which could be acheived by adopting the combined process of cement industry after the sludge being dried by lime. The results showed that certain addition of lime drying sludge could increase the burnability of cement raw materials at 1400℃ held for 60 min, and the content of free lime （f-CaO） in clinkers could meet the national standards. Besides, the phase compositions of cement clinkers with 12% addition of lime drying sludge were fundamentally identical with the control sample. In addition, to guarantee the clinker could meet the cement production quality requiremnet. When the addition of lime drying sludge was excessive, the ingredient ratio of cement should be adjusted according to the sludge composition. The study could provide a scientific and technical support for the utilization of municipal sludge by the combined process of cement industry.