催化裂化钠碱脱硫液中钙镁离子的去除

研究了化学沉淀法和氨基膦酸型螯合树脂吸附法对催化裂化钠碱脱硫液中Ca~(2+)和Mg~(2+)的去除效果。实验结果表明:NaOH沉淀法可有效去除钠碱脱硫液中的Mg~(2+),当溶液pH为12、反应时间为15 min时,Mg~(2+)去除率达91.6%;NaOH-Na_2CO_3联合沉淀法无法去除钠碱脱硫液中的Ca~(2+);经过NaOH溶液有效除Mg~(2+)后的脱硫液再采用氨基膦酸型螯合树脂吸附柱去除其中的Ca~(2+)和Mg~(2+),可使出水硬度小于2 mg/L。提高进水pH、降低进水流量、降低进水硬度均可提高单位体积树脂的处理水量。

Removal of calcium and magnesium ions from sodium alkali solution for FCC flue gas desulfurization

The effects of chemical precipitation process and amino phosphonic acid type chelating resin adsorption process on removal of Ca²⁺ and Mg²⁺ from sodium alkali solution for FCC flue gas desulfurization were investigated. The experimental results showed that：Mg²⁺ could be removed from the sodium alkali desulfurization solution by NaOH precipitation method,and when the solution pH was 12 and the reaction time was 15 min,the Mg²⁺ removal rate was 91.6%;Ca²⁺ could not be removed from the sodium alkali desulfurization solution by NaOH-Na₂CO₃ co-precipitation method;After Mg²⁺ removing with NaOH solution,Ca²⁺ and Mg²⁺ in the desulfurization solution were removed using an amino phosphonic acid type chelating resin adsorption column,and the hardness of the effluent was less than 2 mg/L. The water treatment capacity of the unit volume resin could be increased by increasing the influent pH or reducing the influent flow and the influent hardness.