The typical straw gasification power generation process is mainly composed of six parts: feed device, gas generation system, gas purification system, gas power generation system, control system and wastewater treatment system.

(1) Feeding device; The feeding device generally adopts a screw feeder, which is driven by an electromagnetic speed-regulating motor and regulates the feeding amount of straw materials. The screw feeder can not only ensure continuous and uniform feeding, but also effectively isolate and seal the gasifier from the outside, so that the air required for gasification can only be controlled by the blower to enter the gasifier.

(2) Gas generation system; The gas generation system is mainly composed of inlet fan, gasifier and slag removal screw device. The gasifier has different forms, such as fixed bed gasifier and fluidized bed gasifier, but mainly uses circulating fluidized bed gasifier. Crop straw is converted into combustible gas in the gasifier, and the ash generated after gasification is timely discharged from the furnace by the slag removal screw device.

 

(3) Gas purification system; The combustible gas produced after straw gasification contains a large amount of dust, ash, tar, etc., which can be used for power generation only after purification. For the removal of solid particles and fine dust, multi-stage dust removal technology is generally adopted, such as inertial dust collector, cyclone dust collector, venturi scrubber, electric dust collector, etc. Tar in combustible gas is generally removed by adsorption and water washing, and the main equipment is two spray gas washing towers in series.

 

(4) Gas power generation system; Gas power generation system mainly includes internal combustion engine power generation system, gas turbine power generation system and gas internal combustion unit power generation system. The internal combustion engine power generation system is mainly composed of simple internal combustion units, which can be used to burn low calorific value gas alone or both gas and oil. Its equipment technology is mature and reliable, and it is a common equipment. Gas turbine power generation system requires high quality of gas, and requires high automation control level and gas turbine transformation technology level, so straw power generation technology of gas turbine alone is less. Gas-steam combined hybrid power generation technology is a combined cycle that adds waste heat steam on the basis of internal combustion engine and gas turbine power generation, which can effectively improve efficiency. The straw power generation system of gas-steam combined cycle generally uses gas turbine power generation equipment.

 

(5) Control system; The control system is mainly composed of electric control cabinet, thermocouple, temperature indicator, pressure gauge and air volume control valve. If necessary, computer automatic monitoring system can also be added.

 

(6) Wastewater treatment system; The wastewater from straw gasification and power generation is generally treated by filtration adsorption, biological treatment or chemical coagulation, and then recycled.