The Energy Yield of the Torrefied Coconut Shells

Abstract

Woody and herbaceous biomasses have been utilized as biomass energy plant feedstocks that generate electricity for years. The coconut tree, classified as woody biomass, flourishes throughout tropical regions. Every year, each tree can produce an average of 70 nuts or a maximum of 150 nuts, with each fruit consisting of 15.18% shell. The Philippines has approximately 2.2 million tons of coconut shells each year. The study aims to determine the energy yield of the coconut shells when torrefied. The coconut shells were crushed, torrefied, and analyzed elementally. Initially, the calorific value of raw coconut shells was 30.79 MJ/kg and improved to 34.37 MJ/kg after torrefying at 275°C and held for 30 minutes. The optimal mass yield was 90.10%, while the energy density was 111.64%, resulting in an energy yield of 100.59%. Torrefaction improved the calorific value of coconut shells by 11.63% and optimized the energy yield to 100.59%.