About Mechanical-biological waste treatment
Household, commercial and industrial waste is brought to our treatment facilities where at the mechanical stage waste is broken down into small parts and recyclable material is removed.
During the second biological stage waste is composted and broken down in its biodegradable components. Depending on the input material and processing technology, mechanical-biological treatment can reduce the amount of waste to be disposed of by about 2/3. Moreover, other benefits include the extraction of raw materials, electricity and heat generation.
Principle
The MBT process basically consists of two stages to reduce organic contents of waste.
- 1st stage: mechanical separation of calorific contents which are not biologically degradable.
- 2nd stage: biodegradation (composting) of organic or biologic content which can be degraded within a few weeks.
Input
First in line as input material for MBT is household waste, commercial waste, sewage sludge or suitably pretreated waste (heavy fraction).
Output
Depending on the input material and processing technology, mechanical-biological treatment can reduce the amount of waste to be disposed of by about 2/3.
The output of the MBT consists – among others - of:
- <30% calorific fraction for energy recovery
- 3% recyclable materials (plastics and metal waste fractions)
- <30% landfill fraction
Environmental relevance of MBT
Wider benefits can be drawn from the entire MBT process and subsequent stages:
- Raw materials such as metals, plastics or substitute fuels
- Electricity from the subsequent combustion process and landfill gas power generation
- Heat from utilization in subsequent incinerators