氯碱行业含汞盐泥热脱附过程反应特征

Reaction characteristics of mercury-containing salt sludge obtained from chlor-alkali industry during thermal desorption process

借助DSC-TG、SEM、XRD等分析测试手段,研究氯碱行业含汞盐泥热脱附过程的反应特征。结果表明:采用热脱附方法可实现盐泥中汞的有效去除,当加热温度为500℃时盐泥的去除率为96.7%;盐泥中的主晶相为硫酸钡和碳酸钙,在热处理过程中盐泥的主晶相基本保持不变,结晶度在400℃出现最大值,且伴随新晶相Ca_3Al_2Si_3O_(12)的出现,晶粒尺寸出现下降的趋势,经热处理后的盐泥其空隙丰富,结构较原料疏松。本研究通过探究盐泥脱汞过程的反应特征,可为含汞物料的工业化处理参数优化及过程控制提供技术指导及理论依据。

By the method of DSC-TG,SEM,XRD,and other analytical methods,the changing characteristics of the thermal desorption process of mercury-containing salt sludge were studied.The results showed that the thermal desorption method could effectively remove mercury in the salt sludge,the mercury removing rate was 96.7%when the heating temperature was 500℃.The main crystal phase in the waste were barium sulfate and calcium carbonate during the heat treatment process,and the main crystal phase remained unchanged.At 400℃,the emergence of new crystalline phase of Ca3Al2Si3O12 resulted in maximum crystallinity value and the grain size with a declined trend.The salt sludge after heat treatment had abundant voids and the structure was looser than the raw materials.It could provide a theoretical basis for the parameter optimization and process controlling during the mercury-containing waste industrialized processing.