Overview: Leachate generation is a major problem for municipal solid waste (MSW) landfills and causes a significant threat to surface water and groundwater. Leachate can be defined as a liquid that passes through a landfill and has extracted dissolved and suspended matter from it. Leachate results from precipitation entering the landfill from moisture that exists in the waste when it is composed. Landfill leachate treatment is a major engineering challenge due to the high and variable concentrations of dissolved solids, dissolved and colloidal organics, heavy metals, and xenobiotic organics.
Specific leachate management practices, such as recirculation (bioreactor landfill) and blending landfill gas with leachate, impact quality, resulting in characteristics that vary greatly from site to site. The cold temperature in winter is also a challenge to designing leachate treatment facilities (LTF) in Canada. Traditionally, landfill leachate has been hauled or pumped to off-site wastewater treatment facilities for disposal. Disposal to off-site facilities has generated opposition from plant owners due to more stringent effluent discharge criteria. When discharged to a wastewater treatment facility, leachates can interfere with ultraviolet disinfection by strongly quenching UV light. Leachate may also contain heavy metals and high ammonia concentrations that may be inhibitory to the biological processes. On-site leachate treatment is an alternative to the increasing costs associated with hauling leachate to a local wastewater treatment plant. These treatment facilities are designed to fulfill the specific needs of individual landfill sites and allow discharge to a sanitary sewer or water body without any hauling or disposal costs.
Biological leachate treatment is a proven technology for organics and ammonia removal in young and mature leachate. The anoxic/aerobic processes achieve nitrification and denitrification and reduce the oxygen demand for landfill leachate treatment. Producing an effluent suitable for direct environment discharge, industrial re-use, or irrigation, WATEQ Leachate Treatment Solutions is the complete, on-site leachate treatment solution. Since no two leachates are the same, and the leachate landfill load can vary over time, WATEQ applies either membrane bioreactor or ultra-filtration/reverse osmosis technologies. To create customer savings and ensure short lead times, WATEQ utilizes a modular-system approach to standardize each WATEQ Leachate Treatment Solution. For turn-key operation, the fully automated WATEQ Leachate Treatment Solutions is delivered skid-mounted or containerized.
