| Abstract |
Agricultural waste biomass is one of the most abundant and readily available sources of solid biofuel production. However, to ensure sustainability, it is crucial that the obtained biofuel is energetically efficient. In this study, briquettes were produced from rice husk char (RHC) and crushed rubberwood charcoal (CRC) separately and in combination. RHC and CRC briquettes were respectively labeled RHC10 and RHC0. Mixed biomass briquettes were produced at RHCCRC mass ratios of 2:8 (RHC2), 4:6 (RHC4), 6:4 (RHC6), and 8:2 (RHC8). The combustion properties of the various briquettes were evaluated to determine potential enhancements, and the economic feasibility of production was evaluated. The addition of CRC enhanced the combustion properties of RHC, reducing ash content and increasing fixed carbon. The heating values of the mixed biomass briquettes were higher than the heating value of the RHC briquette. The RHC0, RHC2, and RHC4 briquettes had heating values exceeding 5000 cal/g, meeting the national standards for charcoal briquettes. However, the economic feasibility study revealed that only RHC0 and RHC2 briquettes had a payback period of less than four years, with a positive net present value (NPV) and an internal rate of return (IRR) exceeding a bank interest rate of 7%. Therefore, RHC0 and RHC2 briquettes could be suitable and environmentally friendly alternative energy sources with favorable combustion properties. |