A review on the thermochemical reaction mechanisms for distiller pyrolysis process

Abstract

Circular utilization of distillery byproducts is crucial, and pyrolysis has emerged as a viable technology for converting them into fuels and high-value chemicals. This review investigates the thermochemical reactions of byproducts generated during the grain fermentation process. We begin by discussing the physicochemical properties of these byproducts as they relate to their potential conversion into fuels. Subsequently, we explore various thermochemical processes for biomass-to-energy conversion, including the influence of reaction conditions and catalysts. The intricate interactions between cellulose, hemicellulose, lignin, and protein during pyrolysis are then examined. These interactions, particularly the Maillard reaction between proteins and carbohydrates and vapor–solid interactions, significantly impact the reaction pathways and ultimately the yield and quality of bio-oil, a key product of the pyrolysis process. Understanding these interactions, as evidenced by studies demonstrating the influence of levoglucosan, furfural, and hydroxyacetic acid on product yields, is essential for optimizing pyrolysis processes of distillery byproducts and maximizing the efficiency of biomass energy conversion. By elucidating the theoretical foundation and scientific basis for optimizing the energy conversion of distillery byproducts, this review aims to contribute to the development of sustainable and environmentally friendly practices within the brewing industry.