| 摘要 |
The invention relates to a powder injection system for use in pulverized coal gasification under pressure, which system comprises a reservoir (BK) for stocking the pulverized coal, a plurality of powder injection tubes (SES) and a metering unit (DG). According to the invention, carbon dioxide CO<SUB>2</SUB> is fed to the components that are at operating pressure, namely the powder injection tube and the metering unit, as the inerting and flow medium or fluidizing medium. At the top of the metering unit, nitrogen is fed as the compensating gas, the nitrogen expulsed during the transfer of pulverized coal into the metering unit being fed to the powder injection tube via a pressure compensation line (DAL). The method according to the invention allows reduction of the nitrogen content in the product gas, which nitrogen is caused by the powder injection system and limitation of the problems resulting from the expansion in the powder injection tubes, especially when used in pulverized coal gasification under pressure to produce a synthesis gas for the production of different hydrocarbons. |
