烟煤在双流化床中气化特性初步实验研究

Preliminary experimental study of bituminous coal gasification on dual fluidized beds

利用一套高3 m的双流化床煤气化实验系统,以烟煤为燃料进行了气化初步实验研究.烟煤在气化炉中进行热解气化,生成的半焦经下返料器送入燃烧炉进行燃烧,通过高温循环灰携带能量供给气化炉.通过调整气化炉内料层高度改变燃料在气化炉内的停留时间,从而影响气化效果,料层高度可以通过气化炉内压差进行监测.烟煤气化达到稳定工况时,燃烧炉和气化炉的温度和压差基本保持稳定.燃气热值为5.53MJ/m3,尚未达到中热值标准,原因在于实验装置规模较小导致散热损失较大,同时返料器以空气为返料风降低了燃气品质.

Gasification experiments on bituminous coal were made in an experimental system of dual fluidized beds with 3 m in height.Gasifier was used for coal pyrolysis/gasification.Semicarbon was sent into burner for combustion by U-valve.Energy for gasification was carried by high temperature cycle ash.Status of gasification can be influenced by residence time of fuel which can be changed by adjusting the bed material level in gasifier.Differential pressures in gasifier were used for analyzed the bed material level.The temperature and differential pressure in gasifier and burner maintained stability when gasification condition operated steadily.The calorific value of gas was 5.53 MJ/Nm3 and didn＇t reach the standard of medium heat value.The cause is that the heat loss is bigger in small size and gas quality was decreased by the air which is used as return wind.