Municipal solid waste disposal operational performance in Wa Municipality, Ghana

Background. The generation and management of solid waste pose potential adverse impacts on human health and the environment.

Objective. The present study examines the operational performance of municipal solid waste (MSW) disposal in the Wa Municipality, Ghana.

Methods. The study applied both qualitative and quantitative research methods and modelled the Wa Municipality's MSW disposal system using the municipal solid waste decision support tool (MSW DST). Acid gases (sulphur oxides and nitrogen oxides) and total particulate matter that have a direct impact on human health were set as the objective functions for modelling five MSW disposal scenarios. The modelled scenarios were: 1) landfill disposal only; 2) composting and landfill disposal; 3) composting, incineration, refuse derived fuels (RDF) and landfill disposal; 4) separation, composting, incineration, RDF and landfill disposal; and 5) separation, transfer, material recovery, composting, incineration, RDF and landfill disposal. The pollutants chosen as indicators for substance flow analysis included lead, cadmium, arsenic, mercury, copper, chromium, and zinc.

Results. Scenarios 4 and 5 produced the least engineering cost of 1 150 000 US $/year for the entire MSW disposal system, whereas scenario 2 produced the highest cost of 1 340 000 US $/year. Scenario 5 produced the least average health impacts of −5.812E-04 lbs/year, while scenario 2 generated the highest engineering cost and produced the highest average health impact of 9.358E-05 lbs/year. Scenarios 5 and 4, which included waste-to-energy conversion in the systems, produced the lowest average health impacts (−5.812E-04 lbs/year and −5.611E-04 lbs/year, respectively).

Conclusions. The adoption of an integrated solid waste management concept, including waste-to-energy technologies, will not only help to lessen MSW disposal hazards, but also to produce alternative sources of energy for Ghana and other developing countries.