A Review on Production and Performance Evaluation of Briquettes from Rice Husk, Sawdust, And Black-Currant Leaves for Sustainable Energy Production

Abstract

The global search for sustainable and decentralized energy solutions has resulted in increased interest in biomass briquetting technologies. This study presents a review of briquettes produced from rice husk, sawdust, and black-currant leaves, focusing on physicochemical properties, combustion performance, thermogravimetric behaviour, and techno-economic feasibility. The review was conducted using Scopus and Google Scholar databases for studies published between 2020 and 2025. An initial pool of 213 articles was screened using defined inclusion criteria, resulting in 46 relevant studies for detailed analysis. The results indicate that sawdust exhibits superior fuel properties with calorific values of 16–19 MJ/kg and low ash content (0.5–3%), leading to higher thermal efficiency (30–35%), while rice husk shows high ash content (15–25%) due to silica, which limits combustion efficiency. Black-currant leaves demonstrate high volatile matter (62–68%), enhancing ignition but requiring binder support due to low lignin content. Thermogravimetric analysis reveals three-stage degradation behaviour with activation energies ranging from 160–250 kJ/mol. Composite briquettes improve combustion stability by balancing ignition and durability characteristics. Techno-economic analysis shows production costs of 30–55 USD/tonne with potential profit margins of 40–50% under favourable conditions. Despite increasing research on biomass briquetting, studies are largely concentrated on conventional feedstocks such as rice husk and sawdust, while leaf biomass like black-currant leaves remains insufficiently characterized, particularly in terms of densification and combustion behaviour. In addition, most studies assess physicochemical, combustion, or thermogravimetric properties in isolation, with limited integration into a unified framework linked to real stove performance.