Landfilling
Storage of waste in landfills was the most important method of waste disposal in Germany until 2005. This has been considerably reduced since then and is only an option for waste containing or releasing a small amount of hazardous substances and where these substances display a low level of reactivity. Waste that does not meet these requirements must be treated before landfill using appropriate processes (chemical, physical, thermal and mechanical biological). This waste pre-treatment measure largely prevents the formation of greenhouse emissions or the contamination of groundwater by hazardous substances.
In addition, emission-protection measures are implemented during the building phase of landfill sites.
• Landfills are only established at locations that are geologically and hydro geologically suitable, and are equipped with an impermeable, insulating base layer.
• All the seepage water produced is captured by means of drainage and fed into a purification plant.
• Resultant landfill gases are similarly captured and treated. This allows the energy content of the landfill gases to be used to a large extent.
After backfilling of the landfills, various measures are required for recultivation. Moreover, comprehensive monitoring systems are installed, which are operated for decades after the landfill site is closed.
Landfills are categorised into different classes, namely those for inert, non-dangerous and dangerous waste.
Numerous projects have been conducted on the topic of landfill operation and subsequent maintenance. For example, the following topics have been investigated:
• the connections between the type of waste and the landfill technology, as well as the quality and volume of seepage water and the resultant gas volume.
• decomposition processes and humin content during the decay and landfilling of residual waste.
• usage options for landfill gas.
• methodologies for evaluation of subterranean waste management plants for chemical-toxic waste.
Basic investigations into the thickstock procedure using toxic chemical wastes, particularly filter ash from waste incineration plants, in salt rock
Biological treatment of dump leachate
Characterisation of mineralised deep groundwaters in non-saline solid rocks: investigation of reciprocal reactions with wastes in immission-neutral landfill sites
Comparison and comparative evaluation of different concepts for the underground disposal of toxic chemical wastes
Decomposition and emission behaviour of mechanical-biological pretreated residual waste; bacterial and dust loads in the manual sorting stage
Development of a process for the treatment of landfill sites and other solid wastes emitting hydrogen sulphide
