Optimization of steam gasification system for syngas production using imperata cylindrica

Abstract

The gas can be used as a source of pure hydrogen and carbon monoxide (Rostrup-Nielsel & Christiansen, 2011) or as feedstock for the production of high-value chemicals such as olefins and formaldehyde (Srirangan, Akawi, Moo-Young, & Chou, 2012).

Due to energy crisis and environmental issues, biomass has become a global interest as an alternative to fossil fuel. However, gasification is a highly endothermic reactin, which requires high energy for biomass conversion to syngas. In addition, the usage of steam can increase H₂ content in the syngas, but requires high operational cost due to demand for an external heat source for steam production. Due to this high consumption of energy, it is costly, which requires large investment to satisfy the energy requirement. Therefore, a proper development of gasification system should be investigated for better utilisation of energy, as well as raw material. This study will focus on the development of gasification system, using Imperata Cylindrica, a Malaysian perennial grasses, as a raw material. Perennial grasses was chosen in this study due to its availability everywhere around Malaysia. A primary advantage in utilizing the perennial grass is that less maintenance is required which can persist for 5 to 10 years production of stable amount of biomass (Shinya & Yukihiko, 2008). Calcium oxide(CaO) was used as the sorbent in this study to capture the CO₂ gas produced from the gasification process to enhance H₂ production. The parametric condition for gasification, such as temperature, steam/biomass (S/B) ratio, and sorbent/biomass (CaO/B) ratio will be evaluated and optimised based on the maximum yield of H₂ gas in the syngas.