Abstract: A method for gasifying solid fuel in a co-current gasifier having a fuel silo and a combustion chamber. The method includes a pyrolysis phase in which the fuel decomposes into pyrolysis products, and a gasification phase in which the pyrolysis products are gasified into product gas. Heat transfer from the combustion chamber to the fuel silo is restricted to ensure that the fuel does not dry and pyrolysis does not take place in the fuel silo. The beginning of the pyrolysis is intentionally transferred as close to the gasification phase as possible, and an attempt is made to make the duration of the pyrolysis phase as short as possible. The rise of the fuel temperature is slowed down by transferring heat generated in the gasification phase to a medium, such as gasification air. In the co-current gasifier between the fuel silo and the combustion chamber, there is a cooling channel, which restricts heat transfer and also functions as a preheater for the gasification air.
Abstract: A method for gasifying solid fuel in a co-current gasifier having a fuel silo and a combustion chamber. The method includes a pyrolysis phase in which the fuel decomposes into pyrolysis products, and a gasification phase in which the pyrolysis products are gasified into product gas. Heat transfer from the combustion chamber to the fuel silo is restricted to ensure that the fuel does not dry and pyrolysis does not take place in the fuel silo. The beginning of the pyrolysis is intentionally transferred as close to the gasification phase as possible, and an attempt is made to make the duration of the pyrolysis phase as short as possible. The rise of the fuel temperature is slowed down by transferring heat generated in the gasification phase to a medium, such as gasification air. In the co-current gasifier between the fuel silo and the combustion chamber, there is a cooling channel, which restricts heat transfer and also functions as a preheater for the gasification air.