石灰纯碱法耦合聚合氯化铝预处理高矿化度矿井水的实验研究

Experimental Study on the Pretreatment of High Salinity Mine Water by Lime and Pure Alkali Method Double Alkali Method Coupled Polyaluminum Chloride

高矿化度矿井水回用常采用膜技术进行脱盐,但运行过程中水中硬度和悬浮物会造成膜污染极大影响了膜性能,开展预处理降低矿井水硬度及浊度,对减轻膜污染、提高出水水质、降低运行费用有重要的作用。本文采用石灰纯碱法耦合PAC去除矿井水的硬度及浊度,采用单因素试验考察了药剂投加量、反应时间、沉淀时间对去除效果的影响。试验结果表明,氢氧化钙投加量为100 mg/L、碳酸钠投加量为10 mg/L、PAC投加量为20 mg/L,反应30 min,沉淀15 min,此时水样的总硬度为51.54 mg/L,总硬度去除率为48.11%,浊度去除率为98.13%。吨水药剂费用3.07元。

Membrane technology has a good desalination effect used by high mineralization mine water,but the precipitation contamination caused by calcium and magnesium ions during operation greatly affects the membrane performance.Pre-treatment to reduce hardness plays an important role in reducing membrane contamination,improving effluent quality and reducing operating costs.The lime and pure alkali method coupled with PAC were selected to remove the hardness and turbidity of mine water,and the effects of chemical dosage,reaction time and precipitation time on the removal effect were investigated using single-factor experiments.The optimum conditions were:the dosage of calcium hydroxide was 100 mg/L,the dosage of sodium carbonate was 10 mg/L,the dosage of PAC was 20 mg/L,the reaction was 30 min,and the precipitation was 15 min.The total hardness content of the water sample at this time was 51.54 mg/L,with a total hardness removal rate of 48.11%and a turbidity removal rate of 98.13%.The cost of the chemical for the ton of water was RMB 3.07.