Biomass power generation plays a crucial role in China’s efforts to achieve the “dual carbon” goal. The goal focuses on peaking carbon dioxide emissions and reaching carbon neutrality within a predefined timeline. However, high chlorine and alkali metal contents are naturally present in biomass fuels. Due to this characteristic, biomass boilers are prone to severe high-temperature corrosion during operation. The long-term reliability and safety of boiler systems are undermined by this issue. A systematic and comprehensive review of high-temperature corrosion in biomass boilers is provided in this paper. The corrosion mechanisms, influencing factors, and mitigation technologies are covered, with the aim of providing a valuable reference for both research and engineering practices.

Firstly, the typical characteristics of high-temperature corrosion in biomass-fired boilers are outlined. On this basis, the corrosion mechanisms involving key media such as chlorine, alkali metals, and sulfur are elaborated. Subsequently, the influence of multiple critical factors on corrosion behavior is analyzed in detail. The reaction rate of corrosive processes is directly regulated by temperature. The corrosive environment is changed by flue gas composition. The formation of protective or corrosive deposits is affected by ash composition. The intrinsic corrosion resistance of boiler components is determined by material properties. Finally, a series of prevention and control technologies are summarized. These technologies have been validated through laboratory experiments or long-term engineering practice. They include fuel pretreatment (to reduce corrosive constituents), coating protection (to isolate metal surfaces from corrosive media), additive inhibition (to suppress harmful chemical reactions), and external fluidized beds (to optimize combustion and corrosion conditions). The unique application features, advantages, limitations and economic efficiency of each technology are also discussed.

Future research can be deepened from three key aspects. First, advanced materials science should be integrated to elucidate the microscopic mechanisms of multi-medium coupled corrosion. Interface reactions and damage evolution processes at the atomic and molecular levels can be uncovered. Second, efforts should be intensified to develop novel high-performance protective materials. These materials should be endowed with exceptional high-temperature stability, corrosion resistance and mechanical strength. The harsh operating environments of biomass boilers must be withstood by them. Third, an integrated and collaborative control strategy should be established. This strategy is synergistically combined with fuel pretreatment, scientific additive selection, optimized operational parameters, and advanced material protection. Full-cycle, multi-dimensional corrosion control is the ultimate goal to be achieved. Through the synergistic innovation of mechanism research, advanced material development and systematic prevention-and-control technologies, it is expected to provide essential support for the safe, efficient, and low-cost operation of biomass boilers.