富氧燃烧条件下煤焦特性研究

以大同烟煤为研究对象,在高温携带流模拟反应器上,利用平流火焰燃烧器制取真实富氧燃烧气氛下的煤焦,对不同停留时间下制取的煤焦进行工业分析,讨论停留时间对煤焦的燃尽率、固定碳和挥发份的含量的影响,当停留时间超过94ms时,煤焦的各种参数保持不变.利用热重分析仪进行煤焦的燃烧实验,讨论不同O2/CO2(20/80、30/70和40/60)气氛对煤焦燃烧特性的影响,并采用Coats - Refern法计算煤焦的活化能和指前因子等动力学参数,460～660℃范围内,背景气氛O2/CO2为30/70时煤焦的活化能和指前因子数值最大,为进一步研究煤焦在富氧燃烧气氛中的燃烧反应提供理论依据.

Study of the Characteristics of Coal Coke Under the Condition of Oxygen-enriched Combustion

With Datong-originated bituminous coal serving as an object of study,on a high temperature carry-over flow simulation reactor,coal coke in an atomosphere for real oxygen-enriched combustion was prepared by using Datong-originated bituminous coal and a horizontal flow flame combustor.An industrial analysis was performed of the coal coke prepared at various residence times with the influence of the residence time on the burn-out rate,fixed carbon and volatile content of the coal coke being discussed.When the residence time is over 94 ms,various parameters of the coal coke are kept unchanged.By using a thermogravimetric analyzer,a combustion test of coal coke was conducted and the influence of various atmospheres at different O2/CO2 ratios(20/80,30/70 and 40/60) on the combustion characteristics of coal coke was discussed.Furthermore,the Coats-Refern method was employed to calculate the activated energy,pre-exponential factor and other dynamic parameters of coal coke.When temperature ranges from 460 to 660 ℃ and O2/CO2 ratio of the background atmosphere reaches 30/70,the activated energy and pre-exponential factor of coal coke attain their maximal values,thus offering a theoretical basis for further studying the combustion raction of coal coke in the oxygen-enriched combustion atmosphere.