Leachate is formed as a result of the processes occurring in the interior of stockpiled Municipal Solid Waste (MSW). Landfill leachate is rich in bacterial clusters and contains a variety of concentrated organic and inorganic toxic chemicals that are exceeding the limit of the maximum permissible concentrations (MPC) by ten to hundreds of times. Leachate poses a potential pollution threat to local ground and surface waters and thus has a highly negative impact on the health of nearby areas' population.
The high variability and unpredictability of leachate makes a standard wastewater treatment either inefficient or impossible.
The most modern, efficient and environmentally safe technology for landfill leachate treatment is based on reverse osmosis, whose result meets all current environmental requirements. Reverse osmosis is a physical process based on the passage of a fluid undergoing purification through a semi-permeable synthetic membrane. The fluid to be treated flows from a more concentrated into a less concentrated solution as the result of exposure to a pressure exceeding the difference of osmotic pressures in both solutions.
Reverse Osmosis (RO) plants have found wide application throughout the world. RO Plants are currently used at more than 60 landfill sites in Germany, as well as at 10 sites in Portugal, 7 in Greece, 6 in France and at landfill sites in Malta, Austria, Great Britain, Poland, Romania, Korea and Malaysia. RO Plants are also used at several MSW landfill sites in Russia.