Stoichiometric Water Consumption of Steam Gasification by the FICFB‐Gasification Process

The FICFB (Fast Internally Circulating Fluidized Bed) gasification process [1, 2, 3, 4] is an innovative process to produce a high grade synthesis gas from solid fuels. The basic idea of the FICFB concept is to divide the fluidized bed into two zones, a gasification zone and a combustion zone. Between these two zones a circulation loop of bed material is created but the gases should remain separated. The circulating bed material acts as heat carrier from the combustion to the gasification zone. The design of the gasifier and the use of steam as gasification agent give this process a small heat loss and a nearly nitrogen free product gas with a high calorific value of 13 MJ/Nm3 dry gas. This process has been studied over five years and a lot of experiments were carried out in a 100kWth pilot plant. By using a natural catalyst and gasification temperatures above 800°C the tar content could be reduced below 3 g/Nm3. In former work the general behaviour of this gasification system was studied. In this paper the influence of water on the product gas composition was investigated. As known from literature the steam-fuel ratio has a high influence on the gas composition and the tar content of the product gas.