The new composting facility of Aarhus uses latest technology in turning organic kitchen waste into a fertilizer and soil structure component used by the agriculture.
For several years the Municipality of Aarhus has cooperated with the well-known Danish company Krüger A/S in developing a composting facility for organic kitchen waste from households, based on a new high technology concept. Today, the full-scale composting plant in Aarhus represents successful cooperation between public and private companies financially supported by the Danish Environmental Protection Agency.
30,000 households participating in a full-scale experiment concerning source separation of organic kitchen waste
With an annual capacity of approximately 6,000 tons of organic waste, it is sufficient for the amount of waste collected from 30,000 households which, until now, have participated in a full-scale experiment concerning source separation of organic kitchen waste. Later this year the City Council will decide on the future concept for a permanent source separation system covering the total municipality. Organic kitchen waste will no doubt be a part of this system.
Latest technology promoting the composting
The composting facility has been established as a totally closed process from inlet of the organic waste to outlet of the compost one month later. To promote a rapid process in the composting reactor, the waste is shredded and mixed with 4-6 % cut straw, depending on the content of moisture in the waste. In the reactor, the compost remains for 30 days and is regularly turned over by a mechanical screw system during the process. The moisture content, temperature and air injection are monitored and controlled by a computer. As the temperature rises to 70 degrees C, bacteria, viruses and fungi spores are climinated. When leaving the reactor the compost is finally sieved to remove any remains of inorganic waste, including plastic bags.
The compost meets the standards laid down by the Danish Environmental Protection Agency and is used for agricultural purposes as a fertilizer and soil structure component.
For further information please contact Mr Torben Truelshřj, Chief Engineer, Waste Disposal Department, in the Municipality of Aarhus, Denmark, fax: + 45 8619 7589.
