Highly contaminated landfill leachate
The most frequently employed method of waste management is disposal of waste on a landfill site. However, a major disadvantage of landfill operations is the generation of contaminated leachate caused by rainfall. Water contained in the waste and water released by biological degradation processes also adds to the landfill leachate. Together with the leachate, contaminants are released which come from biological decomposition processes of the landfill material, or are simply washed out. The leachate therefore has toxic properties and contains substances that are not easily biodegradable. Treatment plants with biological processes can only treat the wastewater to a limited extent. Above all, persistent organic substances (measured as chemical oxygen demand, COD), ammonium and halogenated organic substances (measured as dissolved organic halogens, AOXs) are present in the landfill leachate in critical concentrations and have to be removed before discharge into the aquatic environment or transfer to a municipal, biological wastewater treatment plant.