摘要
以炼钢污泥为主要原料制备聚硅硫酸铁铝（PFASS）复合絮凝剂，铁铝总浓度为3．0mol／L。深度处理焦化废水，确定最佳铁与铝物质的量比为9：1，硅与铁＋铝物质的量比为1：30。采用红外光谱、X射线衍射及扫描电镜等手段分析了PFASS的结构与形貌。结果表明：PFASS共聚物为无定型结构；形貌为片状微粒叠加而成的球形；PFASS中部分铁离子、铝离子及其水解络合离子可与聚硅酸起络合反应，生成共聚物。在pH值为7．0～9．0、PFASS的投加量为348mg／L、沉淀时间为40min的条件下，对浊度、色度、CODcr的去除率分别达到98％、68％和61％。
This paper is aimed to introduce our study on using steel- making sludge as the raw material to prepare polysilicate ferric-alu- minum sulfate （PFASS）. We have also investigated the influence of dosage, pH value and sedimentation and confirmed the optimum mo- lar ratio of PFASS through experiments of treating water. As is known, the steelmaking sludge is a by-product of wet-dedusting for basic oxygen furnace, and therefore, over half of its content is iron. In conducting our research, we have first of all collected experimental water samples from the bio-denitrification coking sewage effluent＇. And, then, pre-treatment was given to the steelmaking sludge by grinding and screening （mesh 40）, and, next, by adding sulfuric acid, the filtering solution has been obtained by boiling the sludge for 70 minutes, with vacuum extraction. While adding aluminum sulfate and sodium chlorate in the acid leaching solution, we have prepared poly-ferric aluminum sulfate （PFAS） and oxidative polymerization at 55- 65 ~C. And, so far, it has become possible to obtain the polysilicate ferro-aluminum sulfate （PFASS） by putting some activat- ed silicic acid in the PFAS. Under the condition of molar concentra- tion of Fe ＋ A1 being 3 mol/L, we have explored the effect of molar ratio A1/（Fe ＋ A1） and （Fe ＋ A1）/Si on the coagulation consequence of water sample treating. The above mentioned experimental results show that the optimum proportion of the PFASS should be found as follows： Fe/A1 molar ratio is 9：1, whereas （Fe ＋ A1）/Si molar ratio is 30 ： 1. The morphology and structure of the PFASS can be charac- terized by the Fourier Transform Infrared Spectroscopy, X-ray Diffrac- tion Analysis and Scanning Electron Microscope. At the same time, large polymers have also been proved to be amorphous in structure, spherical in shape and piled up by many sheet powders. The coagula- tion experimental result demonstrates that PFASS is a kind of efficient flocculants with strong turbidity - removal, color-removal and CODcr- removal power than the poly ferric sulfate （PFS） and PFAS. Their removing rates of turbidity, color and CODcr can be made to reach 98% ,68% and 61% respectively on the condition with pH value of 7.0 - 9.0, the dosage of PFASS being 348 mg/L and the sedimenta- tion time 40 min.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2014年第1期207-211,共5页
Journal of Safety and Environment
基金
辽宁省教育厅项目(20060443)
关键词
环境工程学
炼钢污泥
聚硅硫酸铁铝
制备
焦化废水
形貌结构
environmental engineerlng
steelmaking sludge
polysil-icate ferric-aluminum sulfate
preparation
cokingsewage
morphology and structure
