Abstract
In this paper, the technical applicability and treatment performance of physico-chemical techniques (individual and/or combined) for landfill leachate are reviewed. A particular focus is given to coagulation–flocculation, chemical precipitation, ammonium stripping, membrane filtration and adsorption. The advantages and limitations of various techniques are evaluated. Their operating conditions such as pH, dose required, characteristics of leachate in terms of chemical oxygen demand (COD) and NH 3–N concentration and treatment efficiency are compared. It is evident from the survey of 118 papers (1983–2005) that none of the individual physico-chemical techniques is universally applicable or highly effective for the removal of recalcitrant compounds from stabilized leachate. Among the treatments reviewed in this article, adsorption, membrane filtration and chemical precipitation are the most frequently applied and studied worldwide. Both activated carbon adsorption and nanofiltration are effective for over 95% COD removal with COD concentrations ranging from 5690 to 17,000 mg/L. About 98% removal of NH 3–N with an initial concentration ranging from 3260 to 5618 mg/L has been achieved using struvite precipitation. A combination of physico-chemical and biological treatments has demonstrated its effectiveness for the treatment of stabilized leachate. Almost complete removal of COD and NH 3–N has been accomplished by a combination of reverse osmosis (RO) and an upflow anaerobic sludge blanket (UASB) with an initial COD concentration of 35,000 mg/L and NH 3–N concentration of 1600 mg/L and/or RO and activated sludge with an initial COD concentration of 6440 mg/L and NH 3–N concentration of 1153 mg/L. It is important to note that the selection of the most suitable treatment method for landfill leachate depends on the characteristics of landfill leachate, technical applicability and constraints, effluent discharge alternatives, cost-effectiveness, regulatory requirements and environmental impact.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
