Entrained-flow gasifier and gasification method using the same for synthesizing syngas from biomass fuel

A gasifier, comprising:

• a furnace body and a fuel pretreatment system, wherein the furnace body is vertically disposed and comprises a fuel inlet disposed at a lower part of the furnace body, a syngas outlet disposed at a top of the furnace body, and a slag outlet disposed at a bottom of the furnace body;
• the fuel inlet comprises nozzles;
• the fuel pretreatment system is disposed outside of the furnace body, and comprises a fuel crushing apparatus, a sieving apparatus disposed downstream to the fuel crushing apparatus, a first fuel container for receiving particle size-qualified fuel, a second fuel container for receiving particle size-unqualified fuel, and a feeding hopper disposed downstream to the first fuel container;
• the first fuel container and the second fuel container are disposed side-by-side downstream to the sieving apparatus;
• a bottom of the feeding hopper is connected to the furnace body via the nozzles;
• a monitoring unit is disposed close to the syngas outlet at the top of the furnace body;
• the nozzles are disposed radially along the furnace body and are between 2 and 4 in number;
• and
• one or two layers of microwave plasma generators are disposed in parallel at a gasification zone of the furnace body, and each layer of the microwave plasma generator comprises between 2 and 4 working gas inlets.