Waste Minimisation and By-Product Recovery in a Palm Kernel Processing Plant in Edo State

Palm kernel processing generates several valuable by-products including palm kernel cake, palm kernel shell, and palm kernel oil fractions, which are often underutilised or disposed of as waste in small and medium-scale processing operations in Edo State, South South Nigeria. This study evaluates waste minimisation opportunities and by-product recovery potential in a palm kernel processing plant in Benin City with a throughput of 500 tonnes of palm kernel nuts per month. A material flow analysis was conducted to quantify inputs and outputs at each processing stage. The study assesses the calorific value of palm kernel shells as a biomass fuel for steam generation, the protein content and market value of palm kernel cake as an animal feed ingredient, and the residual oil content of palm kernel cake as a function of extraction efficiency. An optimised recovery protocol was designed and piloted over four weeks, incorporating cyclone dust collection, steam pre-treatment of shells for boiler use, and solvent extraction of residual oil from cake. The improved recovery protocol increased total value recovery per tonne of kernel nut by 18 percent and reduced solid waste disposal volume by 42 percent. The study draws on recent industrial ecology and waste valorisation literature for palm oil industries. Findings are relevant to the Edo State Industrial Development Centre and palm kernel processing associations. Keywords: palm kernel, waste minimisation, by-product recovery, material flow analysis, Edo State