Energy Audit on Coconut Shell Charcoal Briquettes Production, Case Study in PT Tom Cococha, Indonesia

Abstract

To increase the competitiveness of Indonesian charcoal briquettes in the global market, the production should be using more efficient energy in order to reduce production cost and getting "green product"label. The first step that can be done is to conduct an energy audit that will help the company to find out the patterns of energy use in its production activities and conduct an analysis to see the energy saving opportunities that can be done. This research aims to conduct an energy audit on the charcoal briquette production process at PT Tom Cococha Indonesia. The production stages which were covered in the auditing are grinding and sieving of the coconut shell charcoal, adhesive mixing, molding, drying, and packaging the product. The result of energy auditing which was conducted in the period of June 22 to 28, 2022, shows that the total energy required for processing coconut shell charcoal into coconut shell charcoal briquettes is 6.00 MJ/kg briquettes. Biomass was the largest energy supplier (42.35% of the total energy required) followed by diesel oil (10.24% of the total energy required), and drying process consumed more than 90% of the total energy required. Due to the high energy demand in the drying stage, a detailed audit has been undertaken on the drying process. There are 2 types of dryer machines which have been used for the drying process. Results of the detailed audit in the drying process shows that the energy required at the drying stage by using a diesel oil-fueled dryer is 3.23 MJ / kg of briquettes with a heat use efficiency rate of 78,6%. As for drying by using a biomass-fueled dryer, it is 3.50 MJ / kg briquettes with a heat use efficiency rate of 76%. According to the findings of a thorough energy audit, the electric motors which were used in the production process have technical efficiency less than 80%. According to the result, energy-saving efforts include implementing an ISO 50001-compliant energy management system and performing regular machine maintenance are strongly recommended to be done.