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排序方式: 共有93条查询结果,搜索用时 15 毫秒
41.
Study on Algae Removal by Immobilized Biosystem on Sponge 总被引:2,自引:0,他引:2
PEI Haiyan HU Wenrong 《中国海洋大学学报(英文版)》2006,5(4):327-332
In this study, sponges were used to immobilize domesticated sludge microbes in a limited space, forming an immobilized biosystem capable of algae and microcystins removal. The removal effects on algae, microcystins and UV260 of this biosystem and the mechanism of algae removal were studied. The results showed that active sludge from sewage treatment plants was able to remove algae from a eutrophic lake's water after 7 d of domestication. The removal efficiency for algae, organic matter and microcystins increased when the domesticated sludge was immobilized on sponges. When the hydraulic retention time (HRT) was 5h, the removal rates of algae, microcystins and UV260 were 90%, 94.17% and 84%, respectively. The immobilized biosystem consisted mostly of bacteria, the Ciliata and Sarcodina protozoans and the Rotifer metazoans. Algal decomposition by zoogloea bacteria and preyingby microcreatures were the two main modes of algal removal, which occurred in two steps: first, absorption by the zoogloea; second, decomposition by the zoogloea bacteria and the predacity of the microcreatures. 相似文献
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传统分离膜因存在渗透性和选择性相互制约、孔隙率低、膜孔尺寸不易控制、化学稳定性和热稳定性差等缺点,在诸多领域应用中受到限制。为了克服上述缺点,目前最有效的方法之一是在膜材料中掺入某些特定纳米材料作为分散相来构筑新型混合基质膜,以增强分离膜的分离性能,同时赋予抗污染性能、高强度等。沸石咪唑酯骨架材料(ZIFs)作为金属有机骨架材料(MOFs)的重要子类,具有独特的孔结构、优异的热稳定性和化学稳定性,是一类构筑混合基质膜的高性能分散相材料。本文主要对应用于水处理领域的ZIFs型混合基质膜及制备方法进行了归类和介绍,并以分离性能和运行稳定性为指标,对ZIFs在膜中掺杂的有效性进行了评估;其次概述了其在脱盐、染料废水处理、重金属离子、大分子蛋白质去除等领域的应用进展;最后总结了ZIFs型混合基质膜材料在科学研究和工程应用中存在的问题,对其今后的发展做出了展望。 相似文献
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水资源污染与水安全问题探讨 总被引:5,自引:0,他引:5
随着工农业生产的发展和人们生活水平的提高,用水量急增,同时大量的工业炉和城市污水绝大部分未经处理便排入水体,赞成对有限水资源的严重污染,这些被污染的水资源相当一部分又作为城市饮用水源,这些水源只通过目前的常规给水处理其质量是不能满足人们对水的基本要求,本文主要分析我国目前水资源状况,水资源合理利用的重要性和强化水处理工艺及保护水资源的措施,提高水的安全性,保持水的可持续利用和社会经济的持续发展。 相似文献
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Ying FU Shuili YU 《中国地球化学学报》2006,25(B08):149-150
Chemical coagulation is very important in water treatment, in which coagulant is an essential part. Pre-polymerized Al^3+ and Fe^3+ products have been used in practice, continuously spread for many years. However, iron-based coagulant has become the focus of studies due to cumulative biologic toxicity of residual Al in treated water. Polyferric sulfate (PFS) and poly-silicic-ferric sulfate (PSF) are all pre-polymerized polymers of Fe^3+ salts. The hydrolysis process and species distribution of Fe^3+ ions have been investigated extensively by many chemists and water-treatment specialists. Generally, the coagulation mechanism of conventional or pre-polymerized coagulants was often studied through jar-test, absorption experiment, microstructure observation or hydrolysis species indirectly. However, few researches have been done on the hydrolysis process of PSF in detail and on the study of the coagulation mechanism using its hydrolysis species distribution until now. In this work, PSF was prepared using water glass, ferrous sulfate and sodium chlorate by a copolymerization method. The hydrolysis species distribution was theoretically derived from pH variation during hydrolysis process of PSF compared to that of polyferric sulfate (PFS), and then characteristics [morphology, species size, Zeta potential, spectra of X-ray diffraction and infrared spectra (IR)] and coagulation performances were explored between them. Coagulation mechanism was analyzed according to hydrolysis species distribution, characteristics and coagulation performances. The results showed that PSF gives different species distribution at different pH values and characteristics from those of PFS, leading to different coagulation mechanisms between the two coagulants. 相似文献
48.
臭氧处理水技术原理及其在水产养殖中的应用综述 总被引:3,自引:2,他引:3
自从1785年发现臭氧以来,臭氧作为氧化剂、消毒剂、催化剂在世界范围内获得广泛的应用,如利用臭氧消毒技术进行饮用水的处理;用于水产养殖用水上,既起杀菌作用,又达到增氧效果,为水产高密度养殖创造有利条件;用于环境消毒、食品保鲜(特别海产品)、储藏、去色、去味、防霉,海水淡化等方面(1、2、3、4、5),由于臭氧处理水法,克服因使用氯和其他化学药品而产生的致癌物质,并造成二次污染,人们也逐渐认识到臭氧处理技术的重要性。水是水生动物的生存环境,水质的好坏直接关系到水产养殖生物成活与否,特别水产动物的苗种生产对… 相似文献
50.
城镇小区污水处理的新技术——人工快速渗滤污水处理系统的研究和应用 总被引:2,自引:0,他引:2
与常规生化法处理生活污水相比,人工快速渗滤工艺(CRI)具有能耗低、投资少、流程短的优点,适宜在土地允许的地区推广. 相似文献