The invention relates to the technical field of
coal gasification, in particular to a
fluidized bed gasifier, a
coal gasification
system and a method, can satisfy the heat requirement of overall reaction in the furnace, have no need for introducing
oxygen burning
coal to provide heat, lower the risk of easy slagging in the gasifier due to introduction of
oxygen, at the same time can promote forward overall reaction in the furnace, have no need for returning substantial synthesis gas to the furnace to increase the
methane yield, and lower the risk of inhibition on overall reaction in the furnace caused by return of synthesis gas to the furnace. According to the
fluidized bed gasifier, the bottom is a gas distribution plate area, a
fluidized bed reaction area is disposed above the gas distribution plate area, a variable
diameter section with a gradually enlarging inner
diameter from the bottom up is disposed between the fluidized
bed reaction area and the gas distribution plate area, thebottom of the
fluidized bed gasifier is equipped with deslagging port, the side wall of the
fluidized bed gasifier corresponding to the fluidized
bed reaction area is equipped with coal inlets, and the lower part of the variable
diameter section is equipped with a carbon carrier inlet.