晶种加速沉淀软化去除反渗透浓水中硬度的研究

Study on Removal of Hardness from Reverse Osmosis Concentrate by Chemically-enchanced Seeded Precipitation Softening

研究了废弃粉末活性炭作为晶种加速沉淀软化,去除浓水中硬度的可行性及效果。结果表明:晶种的引入,能够显著提高硬度的去除效果,初始硬度为1228 mg/L,晶种为2 g/L,碳酸钠为1 g/L,转速为120 rpm时,10 min时硬度去除率可达75.6%,而没有晶种时,达到相似硬度去除效果,则需20 min。系统连续运行时,硬度去除效果随着运行次数的增加而增加,连续运行20次时,出水硬度由287 mg/L降至106 mg/L,去除率由77%增至90%。因此,此方法能取得较好的效果,初步可行。

The feasibility and efficiency of using waste powdered activated carbon as a seed for chemically-enhanced seeded precipitation was studied.The results showed that the hardness removal efficiency could be significantly improved by the introduction of seed.Under the condition of initial hardness 1228 mg/L,seed 2 g/L,sodium carbonate 1 g/L,stirring speed 120 rpm,the hardness removal efficiency was 75.6% at 10 min.However,it was need 20 min to achieve a similar hardness removal efficiency without seed.Under continuous operation mode,the hardness removal efficiency was increased as the number of runs increased.When the number of runs was 20,the hardness of effluent was reduced from 287 mg/L to 106 mg/L,and the removal efficiency was increased from 77% to 90%.In conclusion,good results could be achieved by the method,and the method was preliminary feasible.