Chlorine in biomass co-firing: A review on migration, transformation, impacts, and mitigation strategies

作者：Hejia Chen, Zihao Zhang, Shangyi Yin, Tao Zhang, Tao Song, Ping Lu · 发表于：Carbon Neutral Technologies · 年份：2026 · DOI：10.1016/j.cnt.2026.100022 · 被引用次数：1 · 研究领域：Metal Extraction and Bioleaching、Thermochemical Biomass Conversion Processes、Chemical Looping and Thermochemical Processes

Biomass co-firing is considered a promising pathway for reducing carbon emissions in existing coal-fired power systems; however, its large-scale application is significantly constrained by chlorine-related issues, including slagging, fouling, high-temperature corrosion, and hazardous emissions. This review provides a comprehensive and integrated analysis of chlorine behavior throughout the entire biomass combustion lifecycle, encompassing its sources, speciation, transformation, and engineering impacts. Chlorine in biomass is primarily present as water-soluble inorganic salts and organically bound compounds, with their relative distribution strongly dependent on biomass type. During thermal conversion, chlorine exhibits a temperature-dependent release pattern: organic chlorine is mainly volatilized as HCl and CH 3 Cl at 200–500 °C, whereas inorganic chlorine is predominantly released as gaseous HCl and alkali metal chlorides at temperatures above 700 °C. These processes are further influenced by interactions with alkali metals, sulfur, and mineral phases. Importantly, this review highlights that slagging, fouling, and corrosion are interconnected phenomena governed by the formation, transport, and deposition of alkali chlorides along boiler temperature gradients. Current mitigation strategies, including fuel pretreatment, additive injection, and material protection, are critically evaluated, revealing inherent trade-offs between efficiency and practicality.