【作者】 赵中义；

【导师】 周俊波；

【作者基本信息】 北京化工大学 ， 化工过程机械， 2011， 硕士

【摘要】 以天然碱为原料加工生产小苏打是小苏打生产的主要方法,对于采用溶采方法开采的天然碱矿其小苏打母液(废碱液)循环使用时,由于氯化钠的不断累积,使循环母液的含盐量增加,从而直接影响天然碱矿的回采率和利用率,并且进一步使生产小苏打的质量下降,大量碳酸钠、碳酸氢钠随小苏打母液排掉,不仅浪费了资源,而且造成了环境的污染,因此需要对小苏打母液进行脱盐处理。本文研究了离子膜电解的方法用于天然碱生产小苏打母液电解脱盐,并回收碳酸钠、碳酸氢钠的可行性,探索采用天然碱生产小苏打过程中新的盐碱分离技术。实验首先进行了电解体系的选择,通过对比阴、阳离子膜电解槽电解实验,确定以阴离子膜电解槽对母液进行电解脱盐处理。针对阴离子膜电解的方法,探讨了不同阴离子膜、不同电流密度和不同的阳极电解液及其浓度对小苏打母液电解脱盐电流效率及电解能耗的影响。实验研究结果表明,在小苏打母液电解脱盐过程中,AMI均相阴离子膜对氯离子具有较好的选择透过性,并且其化学性能及机械性能稳定；电解过程中电流效率较高时的电流密度范围为2500-3000A/m2；最后确定了阴离子膜电解槽阳极所采用的最佳电解液及其浓度为25%氯化钠溶液或25%氢氧化钠溶液。天然碱生产小苏打过程中的循环母液经离子膜电解脱盐处理后可继续用于注井洗矿,从而保障天然碱矿体中氯化钠不至于富集,实现小苏打母液的循环利用、清洁化生产,从原理上为含盐碱矿的天然资源的合理开发利用找到一条较为理想的工艺方法。更多还原

【Abstract】 The baking soda is produced by trona as the main method of production of baking soda. When the trone mining is exploited by dissolve mining methods, Mine will produce a large number of filtration, centrifugation mother liquor (spent caustic). When the filtration, centrifugation mother liquor recycling, due to the continuous accumulation of sodium chloride, this will result in the salt content of mother liquor increases, and thus directly affect the recovery rate and utilization of alkaline mineral. This will also enable the production decline in the quality of baking soda. A lot of sodium carbonate, sodium bicarbonate with the filtration, centrifugation mother liquor is drained. This is not only a waste of resources, but also caused environmental pollution.This paper preliminarily studies on the feasibility of the ion-exchange membrane electrolysis technique to desalination and explores new salt separation technology. The salt will be removed by ion-exchange membrane electrolysis from filtration, centrifugation mother liquor, and sodium carbonate, sodium bicarbonate will be recovered, through the anion and cation membrane electrolysis experiment, anion-exchange membrane electrolysis technique is adopted for the mother liquor desalination. For the anion-exchange membrane electrolysis technique, dicussing the influence of different anion membrane different current densities and different anode electrolyte on current efficiency and electrolysis energy consumption of desalination. The results of experiment showed that AMI homogeneous anion membrane is very well in chemical stability, mechanical strength and selectivity for chloride. The optimum current density is 2500-3000A/m2. The optimum anode electrolyte and its concentration is 25% sodium chloride solution or 25% sodium hydroxide solution.Trona mother liquid which is treated by ion-exchange membrane electrolysis can be used for the injection and well washing. This could protect the trone low concentration in sodium chloride and achieve recycling, clean production. In principle, with salt mines for the rational development and utilization of natural resources, we can find a more satisfactory process.更多还原