REHEATZ: RECOVERING WASTE HEAT IN ZAMBIA

The adoption of SDG 13: Climate Action highlights the need to take urgent global action on reducing carbon emissions and the impacts of anthropogenic climate change. Recovering heat from industrial wastewater and recycling this back into their heating systems through Wastewater Heat Recovery (WWHR) processes is a way to reduce both the significant costs and emissions associated with water heating. The Recovering Embedded Heat in Zambia (REHEATZ) project aims to assess the feasibility of WWHR in Zambian food manufacturing, the potential impacts of its implementation, and to identify a pathway towards its wider use. Initial tasks in the project focused on consultation with stakeholders in the Zambian food industry to determine their needs. A strong appetite for the adoption of renewable technologies by Zambian manufacturers was found along with interest from regulators and infrastructure operators in reducing carbon and heat emissions to the environment. A site visit and assessment in several Zambian food manufacturing facilities identified some promising areas where WWHR could be implemented. Of note is the wastewater generated from the blowdown cycle in coal boilers used to generate steam. This wastewater was very hot, over 90°C, and well suited for WWHR due to the proximity of the boiler heating system for any recovered heat to be recycled into. Future work on this project will focus on assessing the economic and social impacts of implementing REHEATZ, developing a pilot WWHR system around wastewater from the boiler blowdown, and implementing heat recovery technologies more widely into Zambian food manufacturing.