Wind energy-driven medical waste treatment with polygeneration and carbon neutrality: Process design, advanced exergy analysis and process optimization

• Published in: Process safety and environmental protection Vol. 178; pp. 342 - 359
• Main Authors: Zhou, Jianzhao, Ren, Jingzheng, He, Chang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-10-2023
• Subjects: Advanced exergy analysis; CCUS; Gasification; Medical waste; Optimization; CCUS; Advanced exergy analysis; Gasification; Optimization; Medical waste
• ISSN: 0957-5820; 1744-3598
• DOI: 10.1016/j.psep.2023.08.040

This study presents a novel and original rich-O2 steam gasification-based process integrated with carbon capture, utilization, and storage (CCUS) for carbon-neutral valorization of medical waste (MW) in Hong Kong. The process employs a calcium loop to capture CO2 from the gasifier-produced syngas, simultaneously facilitating H2 production. The captured CO2 is optionally utilized to generate high value-added products like ethylene, ethanol, and acetic acid through electroreduction. The process incorporates multiple steam Rankine cycles for converting waste heat to power, achieving a total energy efficiency of 71.38%. Advanced exergy analysis reveals over 70% endogenous exergy destruction in reactors and 79.05% avoidable exergy destruction in heat exchangers and condensers, which may be paid more attention. Driven by wind energy, the process has the potential to achieve zero CO2 emission. Economic optimization demonstrates potential profits up to 10410 HK$/h with sufficient wind energy supply and 2548.2 HK$/h with limited supply. This study highlights the novelty of a carbon-neutral MW valorization approach, CCUS utilization, advanced exergy analysis, optimization and renewable wind energy for sustainability and economic viability.