Mechanical biological treatment
A mechanical- biological waste treatment plant (MBT ), also called " mechanical-biological pre-treatment plant " or " substance-specific waste treatment ", is a waste treatment plant for waste from households and firms ( domestic or household-type commercial waste). The breakdown of waste takes place in Europe to a waste type catalog with more than 600 types of waste.
Objective of waste treatment is to treat the case of product manufacture, product use and consumption " sloping " material so that the substances contained in it cause little or no damage as possible of life on earth in general. To achieve this goal, the the producers of waste (household, business, public entity ) is quantity of waste collected by a waste management company, transported to the waste treatment and there treatment depending on the type of waste physically, chemically and / or biologically ( pre-). "Pre- " in the word pre-treatment points to the treatment prior to final disposal, treatment or recovery.
Household waste is characterized by a high content of organic matter ( " organic "). This is depending on the settlement structure ( rural / urban ), socio-economic and cultural factors ( differences between regions and countries ) and the analytical method used and breakdown of waste " trash " into different waste fractions between 30 and 60 %. Other major fractions of household waste are glass, paper, plastics (possibly subdivided ), etc.
Objectives of a mechanical-biological waste treatment
The goals of a mechanical-biological waste treatment are
A consensus as to whether the use of a mechanical-biological waste treatment plant as part of a waste management system is useful or not, can be taken only on the basis of a waste management framework plan for the respective disposal area, since in addition to technical criteria and political ( social evaluate treatment alternatives ) and organizational (operators, financing, fees, etc. ) shall be applied aspects. In Germany, the decision here on fallen in recent years. A total of 46 plants are operated with MBT technology (as of September 2009). In addition to the technical process concept of the "traditional " MBA and shall include the mechanical-biological stabilization (MBS ) and the mechanical- physical stabilization (MPS ).
Process steps of a mechanical- biological waste treatment plant
In terms of technical equipment and combination of the main steps listed there are many variations of MBAs. They range from a simple mechanical and biological treatment is sufficient in open systems, such as on the surface of the landfill ( in many countries, not approvable ), to highly complex from the environment largely closed systems ( with vehicle locks, halls, ventilation devices, closed reactors, etc.).
The equipment of the MBA and thus the Aufgliederungsgrad of material flows depends on the other components of the waste management system from (waste fees, fuel prices, market prices for fuels and other separated fractions, legal requirements, location of the site, distance to neighbors, distance to the disposal site, presence and Distance to an incinerator, personal preferences of decision-makers, etc.). The most important role in the decision for an MBA system plays the treatment price per Mg ( ton) of household waste and the resulting possibly resulting increase in disposal costs overall compared with a pure ( no longer allowed ) landfilling or incineration of the entire waste stream in a waste incineration plant.
For a full cost analysis of the MBA, the costs of all sales broken down streams must be considered. Thus beat, in addition to the pure treatment costs (variable and fixed investment costs), additional transportation, quality control, co-payment for the resulting fuel fractions ( marketing costs ), the cost of incineration in waste incineration ( disposal costs ) and the lawful operation of the landfill for the biologically treated surety to book.
Approaches to reduce these costs through full commercialization of scrap and other valuable fractions (eg plastic, paper, wood), usually succeed only partially made of quality and sales reasons.