Carbon Emission Reduction Potential and Economic Benefits of Introducing Modern Anaerobic Digestion Systems in Slaughterhouses in Ghana: The Case of Kumasi Abattoir

Abstract

Kumasi abattoir, the largest slaughterhouse in Ghana, processes averagely 250 cows, 120 sheep and goats, and 50 pigs daily. Over 180 m3 of wastewater containing blood and pieces of viscera, 7 tonnes of dung and 14 tonnes of intestinal contents are generated daily. Major problems facing the abattoir include the high cost of operation and maintenance of the aerobic wastewater treatment plant and the cost of disposing dung and intestinal contents of slaughtered animals at the Kumasi landfill site. Continuous discharge of untreated wastewater into a nearby stream leads to severe water pollution. The objective of this paper
is to determine the carbon emission reduction potential of Kumasi Abattoir and to evaluate the economic benefits of introducing a modern anaerobic wastewater treatment plant at the abattoir. The modern digester system will stem the release of methane from the indiscriminate disposal of waste. A Clean Development Mechanism methodology for small scale projects was used for estimating emission reductions while a Gold Standard was used in calculating the economic benefits. The results indicate that, the abattoir could generate 80.8 kW of power daily, resulting in about 4,764 ktons CO2 in emission reduction which will yield about USD 67,000 of Verified Emission Reduction and up to USD 2.2 million additional value towards the Sustainable Development Goals. It is also projected that, if the abattoir can process all animals, which currently stands at about 20% in addition to the cattle, the annual net reduction would be 5,312 ktons of CO2 with 90 kW of electricity generation potential and USD 74,368 per annum of VER and up to USD 2.5 million economic value towards the SDGs. It is concluded that replacing the existing aerobic treatment systems at the abattoir with modern anaerobic systems will yield several environmental and economic benefits.