Compost quality from biowaste treatment in West Africa

Vaz, João Miguel; Ferreira, Célia; Pečkytė, J.; Tumaševičiūtė, R.

http://hdl.handle.net/10400.2/14334

Use this identifier to reference this record.

Name:	Description:	Size:	Format:
2015_B3_PP_16_Viana Castelo_Vaz_Joao_compost-quality-9p.pdf		785.23 KB	Adobe PDF	Download

Send Feedback

Authors

Abstract(s)

Composting is generally considered as a cost effective waste management option for stabilising waste and produce a soil improver/organic fertilizer. Passive aerated open windrows is a typical low cost option feasible in in São Tomé and Principe (pop. 197 900), a small island state in West Africa. Here the European Union, in partnership with Instituto Camões, UCCLA and the local authority, invested in the waste management system upgrade. A composting plant integrated with biowaste collection has been working since 2013. In order to assess the composting process efficiency, a novelty in São Tomé on this scale, temperature was regularly measured and registered. The matured compost was analysed in Portuguese Laboratories, targeting parameters such as: humidity, pH, electrical conductivity, organic matter, macronutrients and heavy metals. The results are encouraging suggesting that composting is a good option for treating biowaste collected separately at households, central markets, supermarkets, rest homes, restaurants, municipal gardens…etc. Compost output has high C/N ratio and concentration of organic matter, thus evidencing agronomic value. However, some heavy metals (Cr, Ni) content are a matter of concern, and require further assessment in order to prevent their presence. Besides the financial benefits, composting allows saving natural resources by transforming biowaste into a product, reducing harmful impact of chemical fertilizers to soil. This article paves the way to further research and should encourage more experiences in this field, transforming waste into ready available compost.