Pyrolysis of rice straw: a critical review

Abstract

Rice straw is a common agricultural residue that is readily available. When it is burned publicly, it creates environmental problems, but it may be used in a sustainable way through a process called pyrolysis. This review examines the pyrolysis of rice straw, focusing on the process of converting it into useful products including biochar, bio-oil, and syngas. The yield and characteristics of the products are greatly affected by pyrolysis conditions, which include temperature, residence time, and heating rate. Slow pyrolysis creates biochar that has a higher carbon content and is more stable, making it appropriate for soil amendment and carbon sequestration. On the other hand, fast pyrolysis produces the most bio-oil, which can be processed into renewable fuels. Microwave-assisted pyrolysis and other innovative approaches have the potential to increase energy efficiency and product quality. Pretreatment techniques, including physical, chemical, and biological activities, improve the efficiency of pyrolysis by enhancing the characteristics of the feedstock. Biochar can be used for environmental remediation, energy storage, and heavy metal adsorption, while bio-oil can be used as a sustainable energy source. In addition, rice straw pyrolysis helps to reduce greenhouse gas emissions and makes it easier to collect carbon, which contributes to efforts to mitigate climate change. This review emphasizes the importance of improving pyrolysis techniques to turn rice straw into products that have more value, which provides a sustainable method for managing agricultural waste and producing renewable energy.