Yutaka Terashima* and Hiroaki Ozaki*

* Department of Environmental Engineering Kyoto University

+ Correspondence should be addressed to Yutaka Terashima:
(Yoshida-honmachi Sakyo-ku Kyoto, 606-01 Japan)

Abstract

Landfill leachates including high concentration of inorganic salts have caused various problems both inside and outside treatment facilities. In fact very little inorganic salts in the leachates can be removed by conventional leachate treatment processes. On the other hand, membrane separation processes, which are occasionally employed for water and waste water treatment, have recently received increased attention as possible leachate treatment by achieving a high rejection of inorganic salts, recalcitrant organics and hazardous substances. This paper gives an outline of membrane processes such as reverse osmosis, ultrafiltration and microfiltration, and the methodology and case studies of their application to leachate treatment. On the basis of these results low pressure reverse osmosis was shown to be an effective method for the separation of inorganic salts and recalcitrant organics. The authors propose a newly developed leachate treatment process using membrane technologies combined with biological treatment or coagulation. In addition, the future development of the process as well as its short comings are discussed.

Key words: Landfill leachate, inorganic salts removal, membrane separation, low pressure reverse osmosis, recalcitrant organics