天然土壤絮凝体的强度

Strength of natural soil flocs.

作者信息

Kobayashi Motoyoshi

机构信息

Laboratory of Water Environmental Engineering, Department of Biological and Environmental Engineering, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.

出版信息

Water Res. 2005 Sep;39(14):3273-8. doi: 10.1016/j.watres.2005.05.037.

DOI:10.1016/j.watres.2005.05.037

PMID:16009394

Abstract

To obtain the strength of flocs against breakup is crucial for controlling flocculation in water treatment and predicting transport of colloidal particles in aqueous environments. Recently, the author reported a method to obtain floc strength from a simple experiment of floc breakup subjected to a laminar converging flow. In this study, this method was applied to natural soil flocs. The flocs were formed by coagulation with 0.5 M NaCl (pH 5.4-5.5, pH 6.6) solutions, 0.1M CaCl2 (pH 6.4-6.9) solutions, or acidified distilled water with dilute HCl (pH 5.6). Obtained floc strengths were 0.3, 0.7 and 4 nN for Na-, Ca-, and H-coagulated flocs, respectively. Also, floc strength did not change with floc size. These values of floc strengths were 1-3 orders smaller than those of flocs formed with polymer flocculants and/or precipitated ferric or aluminum coagulants.

摘要

获取絮凝体抵抗破碎的强度对于控制水处理中的絮凝过程以及预测胶体颗粒在水环境中的输运至关重要。最近，作者报道了一种通过层流收敛流作用下絮凝体破碎的简单实验来获取絮凝强度的方法。在本研究中，该方法被应用于天然土壤絮凝体。絮凝体通过与0.5M NaCl（pH 5.4 - 5.5，pH 6.6）溶液、0.1M CaCl2（pH 6.4 - 6.9）溶液或用稀HCl酸化的蒸馏水（pH 5.6）凝聚形成。对于Na -、Ca -和H -凝聚的絮凝体，获得的絮凝强度分别为0.3、0.7和4 nN。此外，絮凝强度不随絮凝体尺寸变化。这些絮凝强度值比用聚合物絮凝剂和/或沉淀铁或铝混凝剂形成的絮凝体的强度值小1 - 3个数量级。