Sustainable valorisation of organic urban wastes

Gepubliceerd op
10 mei 2011

Waste management is a growing challenge in Kenya and other countries in Africa.

Sustainable valorisation of organic urban wastes

The increase in solid waste generation has not been accompanied by an equivalent increase in the capacity of relevant urban authorities to deal with it, nor with a particularly evident expansion of the demand from industrial or agricultural value chains. In a dry continent where soils are seriously depleted and countries like Kenya are facing serious fertiliser shortages, the recovery and valorisation of organic waste in agricultural systems is astonishingly underutilised. Managing organic waste separately is not yet part of the experience – or of the accepted work package – of most African city councils and waste officials, despite the fact that increasing the beneficial use of organic waste as animal feed, compost or energy would contribute to closing the rural–urban nutrient cycles in a sustainable manner.

Understanding the problems and potentials of the organic waste stream is perhaps the single most important step that city authorities could take in moving towards sustainable, affordable, effective and efficient waste management. The Wageningen UR publication Sustainable valorisation of organic urban wastes presents some examples of recent attempts to manage organic waste sustainably in the African context. It contains three case examples of compost production. These include composting by a community-based organisation in the Kenyan private sector and by a public–private partnership in Malawi. In all three cases, the project and case study focus is on the relations between city waste and the agricultural supply chain. A fourth case study describes the technical and economic potential to produce and use biogas from urban organic waste.