Detailed Analysis of Tar Components in Syngas Generated by Lignite Gasification in a Fluidized Bed Gasifier

Fluidized bed gasifiers such as the dual type are used as reactors to produce syngas for hydrogen production and power generation from solid fuels such as biomass and coal. However, the process operates at temperatures below 1173 K, so tar is present in the syngas. The formed tar causes problems such as adhering to the cooling system piping in the subsequent stages of the gasifier, so the tar components are important to identify according to the operating conditions. In this study, lignite was gasified using a laboratory-scale fluidized bed gasifier. The experiments were conducted under various conditions, including pyrolysis under a wide range of temperature conditions, steam gasification under a wide range of steam supply conditions, and the use of porous alumina as a tar adsorbent, and the components of the tar obtained in these experiments were identified. This study proposes an analysis method which combines gas chromatograph mass spectrometry (GC/MS) and field desorption mass spectrometry (FD-MS) to analyze tar components in detail under the above wide range of gasification conditions. This analysis method can be used both for gasification of lignite and for gasification of biomass fuels and mixed fuels of coal and biomass.