Local composting in multi-family houses in town districts
In a sustainable society based on an eco-cycling philosophy it is important to establish efficient waste recycling, as well as systems for re-use. Such systems include both material recovery and the extraction of bio-energy and nutrients using natural ecological techniques. In order to save energy and reduce transportation, which accounts for more than 60 % of the waste handling costs, it is essential to develop small-scale and local systems for the recovery of nutrients from waste products. The organic waste is an important resource of nutrients and should therefore be recycled and put back into the eco-cycling system. Every year in Sweden approximately 2,5 million tons of organic waste is not recycled, but instead incinerated or landfilled (Naturvardsverket, 1996). From an eco-cycling point of view the organic waste should not be landfilled as most of the environmental problems during the lifetime of a landfill is shown to be connected to the organic waste. Landfill gaz, leachate, odours and hygienic problems are all a result from landfilled organic waste, which instead ought to be composed or digested (Naturvardsverket, 1996). Investigations have shown that over 75 % of mixed solid household waste is biologically degradable and that nearly 50 % can be composted and re-used as a nutritious top-soil additive. Therefore, a recent Directive from the European Community prescribes that at least 75 % of the household waste in Europe shall be recycled and re-used by year 2005.
Alm G. (1991) Kompostboken, LTs förlag, pp. 54
Haug R.T. (1993) The practical Handbook of Compost Engineering, Lewis Publishers, Ann Arbor, pp. 717
Hogland W. ( 1999) Optimized composting of source-separated organic fractions of household waste in a vertically fed reactor system, Seventh International Waste Management and Landfill Symposium, Sardinia '99
Naturvardsverket (1996) Aktionsplan Avfall, Rapport 4601, pp. 65-72, 134-135
Warfvinge T. (1997) Environmental Chemistry, Environmental Science in a Biogeochemical Perspective, KFS in Lund AB, pp. 277