洱海湖滨带底泥上覆液混凝/絮凝调理研究

doi:10.19741/j.issn.1673-4831.2021.0187

摘要/Abstract

摘要： 对比阴、阳离子聚丙烯酰胺(APAM、CPAM)和聚合氯化铝(PAC)对洱海湖滨带底泥上覆液中浊度和有机物的调理效果,并进行相关性分析。结果表明:CPAM和APAM主要起粘结架桥作用,浊度去除率分别为53.70%和36.55%,而对溶解性有机物(DOC)的去除率仅为9.75%和10.20%,由于高分子量PAM容易增加水体粘度,不利于胶体颗粒脱稳沉降,随着投加量增大,浊度和有机物浓度不降反升。PAC调理后,上覆液中浊度和DOC的去除率分别为85%和20.87%;三维荧光谱图显示,上覆液中腐殖质含量较高,PAC调理后其特征峰强度减少42%,明显高于PAM的8%。同时,PAC调理上覆液中DOC与浊度、COD和三维荧光光谱(3D-EEM)的相关性(R²=0.905、0.905和0.881)明显高于CPAM和APAM,说明电中和作用对上覆液中腐殖质等DOC调理效果更有效。3种混凝剂/絮凝剂对上覆水调理机理的研究对低浊度水体的处理以及后续工艺有重要指导作用。

关键词: 底泥上覆水, 混凝剂/絮凝剂, 浊度, 有机物

Abstract: The results of previous studies indicate that anionic polyacrylamide (APAM) and cationic polyacrylamide (CPAM) do have bonding and bridging functions. A comparative and analytical study on the effects of APAM, CPAM and PAC (aluminium polychlorid) on adjusting the turbidity and organic matter of overlaying water of the of Erhai lakeshore sediments was conducted. The results of the study show that the turbidity removal rates by using CPAM and APAM were 53.7% and 36.55%, respectively, and the removal rates of dissolved organic matter (DOC) were 9.75% and 10.20%, respectively. High molecular weight substances (PAM) tend to increase the viscosity of water, which is not conducive for the destabilization and sedimentation of colloidal particles. With the increasing of the dosage of PAM, the turbidity and the organic matter concentrations did not decrease but increased. After conditioning the overlying water with PAC reagent, the removal rates of turbidity and dissolved organic matter were 85% and 20.87%, respectively. Results of three-dimensional fluorescence spectrum show that the overlying water had a high content of humus. After conditioning with PAC reagent, its characteristic peak intensity was reduced by 42%, which is much higher than the reduction rate of 8% with PAM reagent. The correlations between DOC and turbidity, COD and three-dimention excitation emission matrix fluorescence spectroscopy (EEM) (R²=0.905, 0.905 and 0.881) were much higher conditioned by PAC than by CPAM and APAM, indicating that charge neutrality has a better conditioning effect on DOC, such as humus, in overlying water. Study on the flocculation mechanism of the three coagulants/flocculants in the overlying water conditioning process can be a basis for future researches on the treatment of low turbidity water and the subsequent process.

Key words: overlying water, coagulant/flocculants (PAC,APAM and CPAM), turbidity, organic matters

中图分类号:

魏华, 郑岩皓, 赵东华, 崔勇涛. 洱海湖滨带底泥上覆液混凝/絮凝调理研究[J]. 生态与农村环境学报, 2022, 38(4): 538-544.

WEI Hua, ZHENG Yan-hao, ZHAO Dong-hua, CUI Yong-tao. Coagulation/Flocculation of Overlying Water from Erhai Lakeshore Sediments[J]. Journal of Ecology and Rural Environment, 2022, 38(4): 538-544.

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