Syngas Production and Combined Heat and Power from Scottish Agricultural Waste Gasification—A Computational Study

Abstract

This paper explores the possibility of utilizing Scottish agricultural waste for sustainable energy, including combined heat and power (CHP). Challenges of using unconventional agricultural feedstocks for gasification are addressed, and the study is focused on the fundamental understanding of gasification processes as well as the design constraints of a commonly used downdraft gasifier. An integrated kinetic and CHP model is presented to address these, and the results demonstrate the optimal working parameters that maximize the production of high-quality syngas and power from the CHP engine. Based on the robust sensitivity analysis, an equivalence ratio (Φ) of 0.3–0.35 with moisture content (MC) less than 10% yields higher production of syngas, thus resulting in higher gasification efficiency. Moreover, an increase in Φ also favors the gasification temperature, which promotes tar cracking and results in lower tar content. Additionally, the gasification efficiency, design limitations, and challenges are addressed to optimize the gasifier design so that it can handle diverse feedstocks with high performance. Therefore, the findings are significant in the field of bioenergy and, in particular, help to expand the route of converting agricultural waste to energy.