Locally available low-cost packing media for anaerobic filters to treat Landfill Leachate

Abstract

Solid waste generated in urban centres is disposed into sanitary landfills or dumping sites. The generated leachate at dumping sites causes many problems leading to various environmental impacts. Hence, it is decided to conduct this research to find out an economical solution that suits to the country for proper treatment of leachate generated at dump sites. As the major portion of municipal solid waste is biodegradable, anaerobic filters well suit to the leachate treatment. As the packing media used for this treatment is highly expensive, finding readily and locally available, low-cost and efficient packing media is a timely need. Therefore, the performances of locally available and low-cost organic and inorganic packing media in treating landfill leachate were studied using a laboratory scale experimental set-up consisting of four packed-bed down-flow anaerobic filter columns. The height and diameter of the cylindrical shaped packed bed were 75 cm and 10 cm, respectively. The first three columns were filled with quartz, saw chips and quarry dust. The fourth column filled by using 25cm height layers of quartz, saw chips and quarry dust respectively. Each column was loaded with landfill leachate. Overall, quarry dust and mixed filter gave higher removal efficiencies than the other media for COD (Chemical Oxygen Demand) and BOD (Biochemical Oxygen Demand). The removal efficiency of turbidity remained around 90% for a long period of the experimental series in quarry dust filter. Mixed and saw chips filters showed higher turbidity removal percentages initially but decreased with the time. According to the experimental results, it was found that quarry dust and mixed filter can be used to treat landfill leachate effectively.