摘要
为改善高灰分煤泥燃烧特性差、难以直接利用等缺点,利用恒温热重实验及动力学分析方法,研究了煤泥及其混煤的燃烧特性,并进一步探究了掺烧烟煤和贫煤、掺混比、以及反应温度等对煤泥混燃特性的影响规律。结果表明:煤泥燃烧后期受灰分阻燃效果明显,燃烧速率明显变慢,燃烧反应活化能为46.92 kJ/mol,高于贫煤而低于烟煤,表现为燃尽困难。煤泥通过掺烧HD、JZ烟煤可有效降低燃烧反应活化能,但烟煤掺入比例为75%会导致“抢风”,挥发分先燃烧消耗大量氧气,导致焦炭燃烧阶段因缺氧而造成燃烧不充分,不利于混煤的燃尽;而当HD烟煤掺入比例25%时,混煤燃烧活化能最低,着火稳定,掺烧效果最佳。相比之下,掺烧CC、SY贫煤对煤泥燃烧特性改善效果较小,且过量掺烧反而会恶化着火特性。此外,800~1200℃区间,随着反应温度升高,燃尽时间缩短,燃烧速率升高,说明提高温度对燃烧反应存在促进作用。
To improve the combustion characteristics and the utilization of high ash slime,the combustion characteristics of the coal sludge and its blended coal were studied by means of isothermal thermogravimetry and kinetic analysis method.A further study was carried out to explore the law of effect of blended coal,lean coal,ratio and temperature on the combustion characteristics.The results show that the inhibitory effect of ash is obvious in the later stage of burning,and the combustion rate becomes slower.The activation energy of coal sludge combustion is 46.92 kJ/mol,which is higher than that of lean coal while lower than that of bituminous coal,thus it is difficult to burn out.The activation energy of sludge combustion can be effectively reduced by mixing HD\JZ bituminous coal,but when the bituminous coal is 75%,it can cause"wind scramble".During the initial volatile combustion,a lot of oxygen will be consumed,leading to an insufficient combustion at the stage of char combustion.Obviously,this is unfavorable for the burnout of blended coal.When the HD bituminous coal is 25%,the activation energy of blended combustion is the lowest,and the combustion is stable.By contrast,the mixing of lean coal with coal sludge has little influence on the combustion characteristics,and the characteristic can be aggravated by adding excessive lean coal.From 800℃to 1200℃,as temperature increases,the burnout time decreases and the combustion rate increases,indicating that by increasing temperature,the combustion behaviors can be promoted.
作者
王栋
王春波
郑菲
岳爽
许紫阳
WANG Dong;WANG Chunbo;ZHENG Fei;YUE Shuang;XU Ziyang(School of Energy Power and Mechanical Engineering,Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology,North China Electric Power University,Baoding 071003,China)
出处
《华北电力大学学报（自然科学版）》
CAS
北大核心
2022年第6期100-108,共9页
Journal of North China Electric Power University：Natural Science Edition
基金
国家重点研发计划项目(2020YFB0606301).
关键词
恒温热重
高灰分煤泥
混煤
燃烧特性
燃烧动力学
isothermal thermogravimetry
coal sludge with high ash
blended coal
combustion characteristic
combustion kinetics
