| 摘要 |
<p>This invention concerns a method for gasifying biofuel (15) in a fluidized bed reactor, where a circulation (3, 4, 6) is maintained that contains fluidized particles and is led through the reactor (1). The invention is characterized in that the gasifying is accomplished at a temperature that is higher than the melting point or sintering point temperature of the ashes produced from the fuel, and that the particles in the fluidized bed (3) are comprised of particles that are of a hard, essentially non-grindable material such as e.g. sand, in admixture with particles that are of an easily grindable, porous material such as e.g. limestone or dolomite, whereby the latter will be pulverized at fluidization all the while they bind ashes to themselves. During the process at least porous particles (17) are added to the circulation (4), and from the circulation are removed finely ground ash containing particles (9, 13) by means of e.g. cyclones (5, 8) and/or a filter (12). A mixture of air (18) and water vapour (19) may be used as gasifying gas. The fuels (15) to be gasified are in particular alkaline matter containing biomaterials such as agricultural waste, or biomass especially cultivated for energy production.</p> |
