Improved structure of biomass gasifier

An improved structure of a biomass gasifier comprises a biomass gasifier. The feeding mode of the biomass gasifier is a closed screw feeding mode. At the same time, positive-pressure air intake is added, a small amount of air of a fan is guided into a feeding screw, and the seal of feeding materials is achieved through materials and intake air pressure. Air intake passages is divided into a main passage and two branch passages, the airflow of the main passage still enters the combustion reaction chamber of the biomass gasifier, an air intake branch passage I is connected with a storage hopper, an air intake branch passage II is connected with the lower end of a centrifugal separation chamber, the position of an air outlet is adjusted to the upper end of a preheating chamber, and valves are arranged in each airflow branch passage to enable each airflow branch passage to be convenient to control. A filter screen is added to the position of the air outlet pipe in the preheating chamber. The improved structure of