神华煤粉在CO2和N2高温气氛下SOx生成释放规律的研究

通过在固定反应床实验系统上,进行了不同燃烧气氛、不同氧气体积浓度、不同燃烧环境温度及不同颗粒粒径下神华煤粉的燃烧实验,在实验过程中对气体污染物SOx生成释放规律进行了研究。发现了CO2气氛下SOx呈现双峰现象,即在煤粉燃烧过程中,S元素转化成SOx的过程分为挥发分释放阶段和焦炭燃烧阶段。SOx释放过程中第一个峰的积分值占总积分值的百分比随着燃烧环境温度的升高而降低,即在较高的燃烧环境温度下SOx主要来源于无机硫化合物。在煤粉燃烧过程中,SOx生成释放曲线的2个峰值随着氧气浓度的升高而增加,SOx总生成量也略为增加;单位氧气消耗量生成的SOx(记为YSOx)随着燃烧环境温度的升高而升高;煤粉颗粒粒径对YSOx的影响规律不明显。高温1 600℃下,煤粉自固硫特性的作用下SOx的生成量与1 000℃时相当。

The Research on SOx Release Characteristics of Shenhua Pulverized Coal Combusted in CO2 and N2 Atmosphere at High Temperature

This paper carried out the Shenhua pulverized coal combustion experiments focusing on the SOx release rule under different atmosphere,O2 concentration,combustion temperature and particle diameter.The tests proved the double peaks phenomenon of SOx release rule,i.e.,the process of sulfur transformation is divided into two stages,the devolatilization process and char combustion process.The percentage of integration of the first peak decreases as the combustion temperature increases proving the main source of SOx is the sulfur contained in char(inorganic sulfide) at high temperature.The two peak values of the SOx release curves increase as the O2 concentration increases and the total amount of SOx increases a little.The SOx yield per O2 consumption(marks as YSOx) increases as the combustion temperature increases.The particle diameter has no obvious effect on YSOx.Under the pulverized coal self sulfur retention mechanism,the YSOx at high temperature(1 600 ℃) is equal to that at 1 000 ℃.