Anaerobic treatment of leachate using sequencing batch reactor and hybrid bed filter

Landfill leachate taken from a young municipal landfill site (approximate to 3.5 years old) containing high organic contaminants (Total Organic Carbon -TOC of about 5000 mg l(-1)) was treated in bench-scale Anaerobic Sequencing Batch Reactors (ASBR) and an Anaerobic Hybrid Bed Filter (AHBF) at mesophilic conditions. Twenty months of testing has been conducted at varied influent leachate concentration of 546-5770 mgTOC l(-1), Hydraulic Retention Time (HRT) of 10-1.5 days and Solid Retention Time (SRT) of 40-9 days in ASBR's, and influent leachate concentration of 1250-4490 mgTOC l(-1) and HRT of 5.1-0.9 days in AHBF. ASBR achieved 73.9% TOC removal at maximum organic loading rate of 2.8 kgTOC m(-3) d(-1) at 1.5 days of HRT, and 65.3% at 0.561 kgTOC kgVSS(-1) d(-1) of maximum specific loading rate and 2 days of HRT. The AHBF maintained 81.4% TOC removal at 1.2 kgTOC m(-3)) d(-1) of loading and 2.4 days of HRT. Methane conversion ratio averaged 0.742 m(3)CH(4) kgTOC(-1) removed at (STP). (C) 1997 IAWQ. Published by Elsevier Science Ltd.