摘要 |
In the process of making synthesis gas in a fluidized bed from carbon and steam, wherein a recirculating stream of carbon from the bed is heated externally of the bed with combustion gases derived by burning carbonaceous solids taken from the bed, using all the fines separated from the synthesis gas withdrawn above the fluidized bed, and such additional carbon from the bed as is necessary to make up the required heat balance, the ash content of the bed is maintained near feed levels by drawing char from the bed, fractionating it to obtain an ash-rich fraction and an ash-poor fraction, returning the ash-poor fraction to the gasifier and sending the ash-rich fraction to the combustor. |