Conversion of cocoa pod shell agricultural residues into high energy density biofuel through torrefaction

Abstract Demand for energy is globally increasing, prompting extensive research into promising renewable energy sources. Agricultural waste is an alternative and sustainable resource for energy conversion. This research focused on utilizing cocoa pod shells (CPSs) to produce solid fuel through torrefaction. The influence of torrefaction parameters such as temperature (220-300°C), residence time (60 and 90 min), and heating rate on the properties of torrefied CPS were explored. The extent of torrefaction effect on the products was studied by proximate and ultimate analyses, as well as measurements of calorific values and energy density. Moreover, thermogravimetric analysis measures the CPS weight loss profile under a nitrogen atmosphere. The obtained data indicated that torrefaction at 260 °C for 90 min yielded optimal results, with a mass yield of 67.47 %, energy yield of 81.52 %, and a HHV of 19.25 MJ/kg. The calorific value of torrefied CPS was found to be comparable to coal, highlighting its viability as alternative solid fuel.