40万t/a离子膜烧碱电解节能技术的应用

Application of 400 kt/a ionic membrane caustic soda electrolysis energy saving technology

分析了离子膜烧碱生产中能耗高的原因,研究应用了阳极液pH值阶梯加酸自动调控、单元槽数字化诊断控制技术,实现了阳极液进出口p H值的精确控制,减少了副反应,延长了离子膜寿命;应用了电解槽在线隔槽稳压技术,实现了运行状态下单台电解槽在线安全并、撤网,避免了压差不稳造成系统跳车;通过分析测定高电流密度下槽电压的变化趋势,及时发现离子膜破损、泄漏等,提高了电流效率。

The reasons of high energy consumption in 400,000 t/a ionic membrane caustic soda electrolysis production were analyzed.The technology of automatic control of pH value of anode solution by step adding acid and digital diagnosis and control of cell were studied and applied.The precise control of pH value at inlet and outlet of anode solution was realized,the side reaction was reduced and the ionic membrane life was prolonged.Baffle voltage stabilization technology realizes on-line safety of a single electrolytic cell and withdrawal of the network,avoiding system jumping caused by unstable voltage difference;through analyzing and measuring the change trend of cell voltage under high current density,it can timely find ion membrane breakage,leakage and so on,thus improving the current efficiency.