无闪蒸溶出主要经济指标测算

Calculation of main economic indicators of non-flash digestion

国内氧化铝行业目前在用的几种主流溶出工艺,均采用料浆闪蒸出二次蒸汽预热低温料浆的方式回收热量,主要差别是采用的设备形式不同,本文介绍了从德国VAW公司全管道化溶出技术一级料浆和料浆换热流程发展而来的无闪蒸溶出技术,其取消了闪蒸过程,全部采用料浆和料浆换热,分析了其理论可行性,介绍了其主要流程,与传统有闪蒸溶出进行了对比,分析了无闪蒸对于溶出系统的影响,并分别以低温溶出、低浓度高温溶出和高浓度高温溶出为例,测算了其主要的经济指标,给出了使用条件,为氧化铝行业从业者深入理解无闪蒸溶出提供了借鉴。

Several mainstream digestion processes currently in use in the domestic alumina industry all use the method of slurry flash evaporation and secondary steam preheating low-temperature slurry to recover heat.The main difference lies in the different type of equipment used.This paper introduces the non-flash digestion technology developed from the one-stage slurry and slurry heat exchange process of the tube digestion technology of VAW company in Germany,which cancels the flash process and uses slurry and slurry heat exchange,and analyzes its theoretical feasibility.This paper introduces its main process,compares it with the traditional flash digestion,analyzes the influence of non-flash digestion on the digestion system,and takes low-temperature digestion,low-caustic concentration high-temperature digestion and high-caustic concentration high-temperature digestion as examples to measure its main economic indicators,and gives the use conditions,which provides a reference for practitioners in the alumina industry to understand the non-flash digestion.