【摘要】 采用慢速和快速两种升温速率,在热解温度为950℃～1500℃范围内制得各种神府煤焦,通过酸洗脱灰处理制得相应的脱灰焦,并采用扫描电镜对原煤焦及其脱灰焦表面灰熔融状况进行观察,结果发现:慢速和快速两种热解条件下,随热解温度提高,灰的熔融状况不同;对原焦样酸洗脱灰处理只能除去表面的部分矿物质;同时,采用等温热重分析法,在反应温度为950℃～1400℃条件下,分别考察了灰未熔融热解煤焦(RP950和SP950)和灰熔融热解煤焦(SP1400和RP1400)脱灰前后的CO2气化反应性.对于灰未熔融热解煤焦脱灰后,其反应活性变化不大,在低反应温时略有下降,而在高反应温度时略有增加.对于灰熔融热解煤焦脱灰后,在整个反应温度范围内,反应活性明显增加,增加的程度取决于反应温度.灰熔融和未熔融热解煤焦及其脱灰焦的气化反应过程都是从低温的化学控制转变到高温的扩散控制.更多还原

【Abstract】 In this paper various slow and rapid pyrolysis Shenfu chars were prepared at pyrolysis temperatures ranging from 950 ℃ to 1 500 ℃,and then deminerilazed through the acid-washing.The characteristics of ash fusion in raw and demineralized chars were observed using the SEM.Those were found that the characteristics of ash fusion in slow pyrolysis chars were different form that in rapid pyrolysis chars,and that ashes of raw chars could only removed partly through the acid-washing.At the same time,the CO₂ gasification reactivities of pyrolysis chars,in which ashes were presented in the unmelted（SP950 and RP950）or melted（SP1 400 and RP1 400）state,were investigated by an isothermal gravimetric analysis at reaction temperatures of 950 ℃-1 400 ℃ before or after demineralization.After the chars with unmelted ashes were demineralized,their reaction activities declined slightly at low reaction temperatures,while increased slightly at high reaction temperatures,which suggested that small changes of their reaction activities resulted from demineralization.However,after the chars with melted ashes were deminerali-zed,their reaction activities increased distinctly at the whole temperature regime and the incremental extent depended on reaction temperatures.The controlling steps of gasification reaction for the two kinds of chars both changed form the chemical reaction at low temperatures to the gas diffusion at high temperatures.更多还原