降低硫酸镍蒸汽单耗生产实践

Production practice of reduce the nickel sulfate steam consumption

大冶有色30万t铜电解项目采用蒸发浓缩和冷冻结晶联合工艺生产粗硫酸镍,在生产运行中存在以下问题:两道工序之间由于生产周期不匹配,很难达到系统生产最大值;生产周期控制较难,系统非生产时间较多。针对以上问题,进行了以下改进措施:通过用蒸发浓缩产生的冷凝水加热蒸发前液,回收热量;优化生产组织,协调浓缩蒸发与冷冻结晶处理量一致性;清理结晶罐内壁,大幅提高热交换效率。改进后,硫酸镍蒸汽单耗由131 t/t NiSO_4·7H_20下降到116t/t NiSO_4·7H_2O,并提高了硫酸镍金属产能,降低了硫酸镍车间的生产成本。

Evaporation and freeze crystallization were combined to produce nickel sulfate in 300 kt/a Copper Electrolytic Refining project in Daye Nonferrous Metals Group Holdings Co.Ltd..The following problems exist in the production running:being difficult to reach the maximum system production due to the mismatch of production cycles between the two processes;production cycle control being difficult,system non-production time more.In response to the above problems,the following improvements were made:the heat was recovered by heating the pre-evaporation liquid with condensed water produced by evaporation concentration;coordinated concentration evaporation and freeze crystallization by optimizing production organization;clean the inner wall of the crystallizing tank to greatly improve the heat exchange efficiency.After improvement,the single consumption of nickel sulfate vapor decreased from 131t/t NiSO4·7H2O to 116 t/t NiSO4·7H2O,and increased production capacity of nickel sulfate metal,and reduced production costs in the nickel sulphate workshop.