【目的】生物质流化床气化炉壁积灰的抑制机制研究可为设计热效率更高、稳定运行的气化炉提供基础数据。【方法】以自主设计的沉积探针对玉米秸秆和马尾藻气化的炉壁内/外层积灰进行收集,以Shell炉煤气化飞灰(Shell灰)作为添加剂结合IC、ICP-MS、SEM和XRD等分析方法对积灰抑制特性进行定量表征分析。【结果】结果表明玉米秸秆和马尾藻气化内层积灰形成过程中,碱金属/碱土金属硫酸盐和碱金属氯化物的冷凝分别发挥了重要作用。当Shell灰在两种物料中的添加比例(质量比)分别为<15%和<10%时,相对熔点更高的白榴石和正长石等物相的形成抑制了灰颗粒间的黏附,促使外层积灰结构疏松脱落。抑制机理表明外层积灰的碱酸比(RB/A)及n(SiO2+Al2O3)均能有效反映Shell灰对外层积灰趋势的影响。

【Purposes】 The research on the inhibition mechanism of ash deposition on the furnace  wall of biomass fluidized bed gasification can provide fundamental data for the design of gasifiers with  higher thermal efficiency and stable operation. 【Methods】 In this study, a self-designed deposition  probe is used to collect the inner/outer layer of ash depositions on the furnace wall of corn straw and  sargassum horneri, and Shell gasifier coal fly ash (Shell ash) is used as an additive. Analytical methods  of IC, ICP-MS, SEM, and XRD are employed to quantitatively analyze the inhibition properties of  ash deposition.【Findings】 The results indicate that the condensation of alkali metal/alkaline earth  metal sulphates and alkali metal chlorides play an important role in the formations of ash in the inner  layers of corn straw and sargassum horneri gasification. When Shell ash is added at <15%  and <10% to the two materials(mass ratio), the formation of phases such as leucite and orthoclase,  which have higher relative melting temperatures, inhibits the adhesion of the ash particles and con‐ tributs to the loosening of the outer layer deposition ash structure. The inhibition mechanism suggests  that both the base-to-acid ratio (R ) and n(SiO +Al O ) of the outer layer can effectively reflect the  effect of Shell ash on the tendency of the outer layer deposition ash.