低温低浊进水下壳聚糖及其衍生物助滤效果研究

Study on the Enhancement of Filtering Effect of Low Temperature and Low Turbid Water by Chitosan and its Derivatives

针对黄河下游水库水质冬季呈现低温低浊、处理难度大的特点,采用壳聚糖(CTS)、低聚合度壳聚糖(LCTS)、质子化壳聚糖(HCTS)和羧甲基壳聚糖(CMCS)助滤剂进行二次微絮凝过滤模拟实验。结果表明,低温低浊水质下CTS、LCTS、HCTS可有效降低滤池出水浊度,当CTS投加量为0.6 mg/L时,浊度可将至0.1 NTU;质量分数0.2%的稀盐酸代替质量分数1%的冰乙酸溶液溶解CTS可有效解决滤池出水因投加CTS助滤剂引起水中pH降低、滤池出水TOC含量升高等问题;降低进水pH,可提高CTS强化过滤效果;pH为6时,出水浊度降至0.1 NTU左右,颗粒数降至320 CNT/m L。

The water quality in the lower reservoir of the Yellow River is characterized by low temperature and turbidity in winter and difficult to treat. The simulated filtration test of dual micro-flocculation was carried out by CTS, LCTS, HCTS and CMCS, respectively. The results showed that CTS, LCTS and HCTS could effectively reduce the effluent turbidity of the filter in low temperature and low turbidity condition. When the CTS dosage was 0.6 mg/L, turbidity could be down to 0.1 NTU. In addition, the diluted hydrochloric acid solution with 0.2% mass fraction was substituted for the glacial acetic acid solution with 1% mass fraction, which could effectively solve the problems of pH decrease and TOC content increase in effluent caused by CTS addition. Lowering the pH of influent could improve the filtration effect of CTS. When the pH was 6, the effluent turbidity reduced to about 0.1 NTU, and the number of particles dropped to 320 CNT/mL.