Towards circular economy solutions for the management of rice processing residues to bioenergy via gasification

Vaskalis, Ioannis; Skoulou, Vicky; Stavropoulos, George; Zabaniotou, Anastasia

Abstract

An economic assessment of two circular economy scenarios of fluidized bed gasification-based systems for combined heat and power (CHP) generation, fueled with rice processing wastes, was conducted. In the first scenario, the gasification plant with a capacity of 42,700 t/y of rice husks provides a waste management solution for 5 small rice processing companies, located at the same are, while in the second scenario the gasification unit of 18,300 t/y capacity provides a waste management solution to only one rice processing plant, being a custom-made solution. The first scenario is the most economically viable, with an annual revenue of 168 €/(t*y), very good payout time (POT=1.05) and return in investment (ROI=0.72). The economic assessment was based on experiments performed at a laboratory-scale gasification rig, while the economic analysis was based on the SMARt-CHP technology, developed at Aristotle University, Greece. The experimental proof of concept of rice husks waste gasification was studied at a temperature range 700-900oC, under an under-stoichiometric ratio of O2/N¬¬2 (10/90 v/v), as gasification agent. Producer gas’s LHV maximized at 800oC (10.9 MJ/Nm3), while the char’s BET surface reached a max of 146 m2/g at 900oC. Recommendations were also provided for a potential pretreatment of rice husks in order to minimize de-fluidization problems of the gasification system.

Citation

Vaskalis, I., Skoulou, V., Stavropoulos, G., & Zabaniotou, A. (2019). Towards circular economy solutions for the management of rice processing residues to bioenergy via gasification. Sustainability, 11(22), Article 6433. https://doi.org/10.3390/su1122643

• Journal Article Type: Article
• Acceptance Date: Nov 12, 2019
• Online Publication Date: Nov 15, 2019
• Publication Date: 2019-11
• Deposit Date: Nov 16, 2019
• Publicly Available Date: Nov 18, 2019
• Journal: Sustainability
• Electronic ISSN: 2071-1050
• Publisher: MDPI
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 22
• Article Number: 6433
• DOI: https://doi.org/10.3390/su1122643
• Keywords: Circular economy; Rice husks; Waste management; CHP; Gasification; Economic assessment; Ash pretreatment
• Public URL: https://hull-repository.worktribe.com/output/2640073
• Publisher URL: https://www.mdpi.com/2071-1050/11/22/6433
• Contract Date: Nov 16, 2019