A review of landfill leachate induced ultraviolet quenching substances: Sources, characteristics, and treatment. (15th November 2018)

• Record Type: Journal Article
• Authors: Iskander, Syeed Md; Zhao, Renzun; Pathak, Ankit; Gupta, Abhinav; Pruden, Amy; Novak, John T.; He, Zhen
• Is Part Of: Water research. Volume 145(2018)
• Page Start: 297
• Page End: 311
• Publication Date: 2018-11-15
• Subjects: Landfill leachate -- UV absorbance -- UV quenchers -- UV disinfection -- Recalcitrant organic carbon; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2018.08.035
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: Landfill leachate contains extremely diverse mixtures of pollutants and thus requires appropriate treatment before discharge. Co-treatment of landfill leachate with sewage in wastewater treatment plants is a common approach because of low cost and convenience. However, some recalcitrant organic compounds in leachate can escape biological treatment processes, lower the UV transmittance of waste streams due to their UV-quenching properties, and interfere with the associated disinfection efficacy. Thus, the leachate UV quenching substances (UVQS) must be removed or reduced to a level that UV disinfection is not strongly affected. UVQS consist of three major fractions, humic acids, fulvic acids and hydrophilics, each of which has distinct characteristics and behaviors during treatment. The purpose of this review is to provide a synthesis of the state of the science regarding UVQS and possible treatment approaches. In general, chemical, electrochemical, and physical treatments are more effective than biological treatments, but also costlier. Integration of multiple treatment methods to target the removal of different fractions of UVQS can aid in optimizing treatment. The importance of UVQS effects on wastewater treatment should be better recognized and understood with implemented regulations and improved research and treatment practice. Graphical abstract: Image 1 Highlights: Co-treatment of landfill leachate with municipal wastewater is a common approach. Recalcitrant organic compounds in leachate can decrease UV disinfection efficiency. UVQS consist of three major fractions, humic acids, fulvic acids and hydrophilics. Combination of different treatments can reduce UVQS concentrations in leachate. The importance of UVQS to wastewater treatment should be better recognized.