The Optimal High Heating Value of the Torrefied Coconut Shells


  • R. Espina School of Engineering and Architecture, Ateneo de Davao University, Philippines
  • R. Barroca School of Engineering and Architecture, Ateneo de Davao University, Philippines
  • M. L. S. Abundo Engineering Graduate Program, School of Engineering, University of San Carlos (USC), Talamban, Cebu City, Philippines | Rolls-Royce@NTU Corporate Lab, Nanyang Technological University, Singapore


Coconut is a biomass resource that is abundant in tropical countries. In 2020, the Philippines planted 347 million coconut trees that produced 14.7 million tons of coconuts. The coconut shells (endocarp) are considered a waste material, which comprise 15.18% of each fruit and account for 2.2 million tons. The calorific value of raw coconut shells is 30.79MJ/kg. When torrefied at 275°C for 30 minutes holding time, the calorific value reached the optimal of 34.37MJ/kg, representing an increase of 11.64%. The mass yield (My) was 90.10% and the energy density was 111.64%, resulting in an energy yield of 100.59%.


coconut, shells, torrefaction, downdraft, gasifier, gasification, gas synthesis


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How to Cite

R. Espina, R. Barroca, and M. L. S. Abundo, “The Optimal High Heating Value of the Torrefied Coconut Shells”, Eng. Technol. Appl. Sci. Res., vol. 12, no. 3, pp. 8605–8610, Jun. 2022.


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