神东矿区气化用煤的煤灰黏温特性及调控试验研究

Study on coal ash viscosity temperature characteristics and regulation experiment for gasification coal in Shendong mining area

煤灰黏温特性是影响气流床气化炉稳定运行的关键指标之一,即研究气化用煤的煤灰黏温特性对气化炉的稳定运行至关重要,而煤中矿物质种类和组成直接影响煤灰特性,因而选用典型矿区的气化用煤进行相应的煤灰黏温特性调控试验研究很有必要。选用神东矿区煤A和煤B为研究对象,利用扫描电镜、煤灰高温黏度测定仪等设备,研究分析煤灰特性和配煤对煤灰黏温特性调控的可行性。结果表明:煤A和煤B的煤灰熔融性温度均较低,5~25 Pa·s对应的温度区间均超过120℃,符合液态排渣气化工艺对煤灰黏度的要求;神东矿区典型气化用煤的主要矿物包括黏土矿、方解石、黄铁矿、菱铁矿和石英等,其中黏土矿物以伊利石为主。煤灰黏温特性主要受煤中矿物质类型、含量以及赋存形态影响。为了保障气流床气化炉顺利排渣及工况稳定,对神东矿区典型气化用原料煤的煤灰特性以及矿物组成采取配入不同矿物组成的煤,可达到调控煤灰特性及提高气化炉转化效率的目的。

The viscosity-temperature characteristics of coal ash is one of the key indexes which affects the stable operation of entrained flow gasifier.It is very important to study the viscosity temperature characteristics of coal ash for the stable operation of gasifier.The type and composition of minerals in coal directly affect the characteristics of coal ash.Therefore,it is necessary to study on the regulation experiment of the viscosity temperature characteristics of coal ash for the gasification coal from typical mining area.The coal A and coal B in Shendong mining area were selected as the research object.The study on the coal ash characteristics and the feasibility of coal blending on the control of coal ash viscosity temperature characteristics were done.The results show that the coal ash melting temperatures of coal A and coal B are relatively low,and the temperature range corresponding to 5-25 Pa·s is above 120℃,which meet the requirements of liquid slag gasification process for coal ash viscosity.The main minerals in coal A and coal B include clay ore,calcite,pyrite and siderite.Illite is the main clay ore.The viscosity temperature characteristics of coal ash are mainly affected by the type,content and occurrence form of minerals in coal.It is necessary to control the ash characteristics of raw coal by adding coal with different mineral composition,to ensure the smooth slag discharge and stable condition of entrained flow gasifier.