Circular bioeconomy potential and challenges within an African context: From theory to practice

A circular bioeconomy has the potential to minimize the environmental impacts of biowaste while simultaneously generating value-added bioproducts and bioenergy. Currently, most countries of the African Union lack well-defined policies, requisite infrastructure, and expertise for biowaste valorisation, thus limiting the potential development of the region. Against this background, it is necessary to deploy circular bioeconomy principles based on the awareness of the biocapacity of territories through the nexus of biowaste management and life cycle thinking. In the present study, a preliminary assessment of waste management practices in a tourist hotel in Victoria Falls in Zimbabwe is explored. The hotel produces about 3.26 tons per month of biowaste, which is often improperly disposed in non-engineered waste dumps. Furthermore, the disposal options for 1 tonne of biowaste are explored using City of Harare (CoH) as a case study. The preliminary results show composting as the most environmentally favourable option (9.6 kg CO2 eq), followed by anaerobic digestion (56.4 kg CO2 eq), and finally, biowaste incineration (140 kg CO2 eq). Anaerobic digestion and composting remain the most viable biowaste disposal alternatives in Africa, due to limited expenses and expertise for construction, operation, and maintenance. However, both technologies remain under-utilized, hence, a significant portion of the source-separated biowaste is still disposed of in waste dumps and this reflects the lack of supportive institutional, regulatory and policy frameworks. Overall, these early results point to the potential to develop a circular bioeconomy in Africa, while calling for shared responsibilities among the state, market, and civil society actors to develop and adopt appropriate institutional, regulatory, policy and funding models.