USE OF PURE CARBON DIOXIDE AS AN INERTING AND FLOW MEDIUM IN POWDER INJECTION SYSTEMS FOR USE IN PULVERIZED COAL GASIFICATION UNDER PRESSURE

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, pure carbon dioxide (CO₂) 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. The carbon dioxide-carrying components are heated in such a manner that the temperature is above the threshold of the diphase range. The method according to the invention allows elimination of any nitrogen in the product gas, which nitrogen is caused by the powder injection system, especially when used in pulverized coal gasification under pressure to produce a synthesis gas for the production of different hydrocarbons.