Liquid-Quench Sampling System for the Analysis of Gas Streams from Biomass Gasification Processes. Part 2: Sampling Condensable Compounds

The performance of a continuous liquid-quench-based sampling system is presented, with regard to the sampling of condensable compounds. Toluene is used as a model molecule representing tars commonly found in the gas streams of biomass gasification plants and related research units. It is shown that the operational parameters of the sampling system can be adjusted for a correct sampling of condensable compounds. Moreover, the systematic measurement uncertainty caused by the use of the sampling system is evaluated in the case of the characterization of a raw producer gas from a bubbling fluidized-bed gasifier considering both condensable and noncondensable compounds. It is concluded that the systematic uncertainty is small for H-2, CO, CH4, C7H8, and C10H8, comparable to the random measurement uncertainty for C2H4, C2H6, N-2, H2O, and C6H6 and larger than the random measurement uncertainty for CO2, C2H2, C3H6, and COS.