高硫煤高温燃烧固硫试验研究

Sulfur-fixing experiment of high-sulfur coal combustion at high temperature

为了研究高硫煤的高温燃烧特性,采用Ca(OH)2作为主固硫剂,镁助剂、锰助剂、铁助剂和钠助剂为固硫助剂,选用全硫含量为4.04%的攀枝花高硫煤为研究对象,在最佳钙硫物质的量比为1.7的条件下,采用X射线衍射仪(XRD)和X射线荧光分析仪(XRF)对固硫灰渣进行表征,揭示固硫产物的生成机理,进而得出固硫灰渣与固硫率的关系,采用热重分析法对煤样的燃烧特性和反应动力学进行分析研究。结果表明,固硫率与固硫灰渣中SO3含量呈正相关,与Ca/S物质的量比呈负相关。添加剂的加入使煤样的燃点略有提高,燃烧由一段燃烧变成两段燃烧,煤样燃烬时间缩短。通过对煤样低温段和高温段的动力学分析发现,燃烧速率随平均表观活化能的增大而增大,添加剂的加入使煤样的整体燃烧性能提高。

In order to study the combustion characteristics of high-sulfur coal at high temperature,Ca（ OH）_2 was selected as the main sulfur-fixing agent,Mg additive,Mn additive,Fe additive and Na additive were selected as sulfur-fixing additives and typical Panzhihua high-sulfur coal was selected as the research object,the content of total sulfur of Panzhihua coal was 4.04%.Through the experiment,the best mole ratio of Ca / S was 1.7.The sulfur-fixing ash of coal combustion was characterized by X-ray diffractometer（ XRD） and X-ray fluorescence analyzer（ XRF）.The results revealed the formation mechanism of sulfur-fixing products,then drew the relationship between sulfurfixing ash and sulfur-fixing efficiency.It was found that the sulfur-fixing efficiency was positively correlated with SO_3 content and negatively correlated with the mole ratio of Ca / S in the sulfur-fixing ash. The combustion characteristic and kinetic analysis of coal samples were investigated with thermal gravity analysis method.The results showed that the ignition temperature of coal samples was all improved slightly with adding additives.The combustion process became into two-section combustion and the burning time was shortened.Through kinetic analysis of coal samples at low-temperature and high-temperature,it was found that the burning rate of coal samples were increased along with the increase of the average apparent activation energy,and the whole combustion performance of coal samples was improved when adding additives.