Transforming Market and Slaughterhouse Wastes into Compost for Sustainable Agriculture

Aims: Management of organic waste from markets and slaughterhouses is a major challenge for African cities. The disposal of these wastes in landfills or simple abandonment without treatment constitutes a significant pollution source to surface and groundwater due to the infiltration and runoff of organic and mineral compounds. The present study aims to simultaneously use those wastes for agricultural use through composting to mitigate water pollution and establish sustainable waste management. Study Design: Market and slaughterhouse wastes were firstly collected. One part of these has been dried before composting process. Both dried wastes and composts from the above mentioned process were characterized by weighting and physico-chemical analyses. Then the effect of composts has evaluated on crops development and yields. In fine, this effect has been optimized with biochar produced with rice husks. Place and Duration of Study: Market wastes were collected at Sinistre Market and slaughterhouse wastes were collected at municipal slaughterhouse of Korhogo, between December 2024 to January 2025. Composting and plot experiments were carried out from February 2025 to March 2025 Methodology: Wastes were collected from Sinistre Market over 22 days and at municipal slaughterhouse of Korhogo over 55 days. Before composting process, wastes have been weighted and one part dried. Composting process have used Berkley method (18 days), which consists in superimposing layers of dry materials rich in carbon and fresh materials rich in nitrogen to form piles (pyramidal pile) of at least 0.90 m³ which will undergo periodic reversals. A sample of 1 kg of each produced compost was taken, dried and following physico-chemical parameters were analyzed: total nitrogen, phosphorus, potassium, pH, cation exchange capacity, electrical conductivity, calcium, sulfur, carbon. Laboratory Analyses were done by using Mehlich 3 method, along with an infrared spectrometer. The influence of resulting compost on okra (Abelmoschus esculentus) crops has been evaluated compared to control and NPK treatment. Results: Collecting data revealed substantial generated wastes: about 1,244 kg of fresh market wastes was collected and 26,000 kg of fresh viscera from the slaughterhouse collected. Physicochemical analyses confirmed high nutrient content of obtained composts, with concentrations of nitrogen ranging from 4 to 4.3 g/kg, phosphorus contents from 4.6 to 6.3 g/kg, and potassium lelvels from 19.4 to 20.6 g/kg. the application of produced composts improved significantly the growth and yield of okra. The best results has been achieved with compost from slaughterhouse dry matter in association with fresh market matter and ¼ to ½ quantity of biochar, yielding 3.2 kg, compared to 0.42 kg in control plots. Conclusion: These results indicate that co-composting of market and slaughterhouse wastes reduces the environmental impact of wastes disposal, while providing a viable alternative to chemical fertilizers in agriculture.