生物质灰添加对无烟煤煤焦气化特性的影响

以遵义无烟煤煤焦为气化原料,以稻草灰和棉秆灰为生物质灰添加剂,基于热重分析仪开展焦样-CO_2等温气化实验,以探究生物质灰添加对煤焦气化反应特性的影响,并基于气化过程焦样固体结构演变对其进行关联解释。研究表明,稻草灰和棉杆灰的添加有利于提高煤焦气化反应活性,这主要归因于生物质灰添加有利于气化过程煤焦活性矿物质含量增加和碳结构有序度降低。且稻草灰和棉秆灰的添加对焦样气化反应活性的增加幅度随气化温度升高而减小,这可解释为生物质灰添加对气化过程煤焦活性矿物质含量增加和碳结构有序度降低的幅度随气化温度升高而减小。此外,棉秆灰对煤焦气化反应活性的促进作用较稻草灰更为显著,这主要由于棉杆灰的添加对气化半焦中活性AAEM含量的增加作用以及碳结构石墨化进程的抑制作用更加明显。

Effect of biomass ash addition on gasification characteristics of anthracite char

Zunyi anthracite was used as the raw material of gasification and rice straw ash and cotton stalk ash were optioned as biomass ash additives. Char-CO₂ isothermal gasification experiments were conducted using TGA to investigate the effect of biomass ash addition on coal char gasification characteristics. Furthermore, the relationship between char structure evolution during gasification and char gasification reactivity was investigated. The results indicate that the biomass ash addition has a promotion effect on coal char gasification, which is well related to the increase in active AAEM content and the decrease in the order degree of carbon structure of chars by the addition of biomass ash. However, the promotion effect of biomass ash additives on coal char gasification is weakened with increasing gasification temperature, mainly due to that the positive effect of biomass ash additive on the increase of active AAEM content in char and the inhibition effect of biomass ash additive on carbon structure order degree of coal char become weaker at higher gasification temperature. Additionally, it is found that cotton stalk ash has a more significant positive effect on coal char gasification than rice straw ash because cotton stalk ash has a more obvious effect on the increase in active AAEM content and the decrease in the carbon structure graphitization degree of coal char.