Recovery of humic substances from landfill leachate via 2500 Da ultrafiltration membrane

Abstract

Landfill leachate management is getting more and more attention because of its seriously potential environmental impact. Humic substances (HS), which lead to the difficulty of landfill leachate treatment, can also be recovered and used as a fertilizer for soil or remediation agent for contaminated sites. A 2500 Da ultrafiltration membrane was applied to separation of humic substances from salts and heavy metals in landfill leachate in this study. Humic substances recovery ratio was 50-70%. The fractional recovery of HS decreased from up to 100% to about 55% as concentration factor (CF) increased from 2 to 6. Fractional removals of K+, Na+, Mg2+, and Ca2+ were up to 85%, 85%, 89%, and 51%, respectively. Fractional removals of heavy metals were more than 75%, 60%, and 78%, respectively. The 2500 Da UF performed well in separating HS from salts and heavy metals and in concentrating HS. © 2011 WIT Press.