Variation of feedstock in a dual fluidized bed steam gasifier—influence on product gas, tar content, and composition

Abstract

A steam blown dual fluidized bed gasification plant was used to yield a nitrogen (N2) free product gas (synthesis gas) from various biomass fuels. In addition to the variation of process parameters like temperature, steam to carbon ratio, fluidization rate, and the influence of different bed materials, various feedstock inputs affected the generation of the product gas. This study focuses on the gasification of different biomass feedstock. The variation of biomass implies wood chips, wood pellets, sewage sludge pellets, and straw pellets. The chosen evaluated experimental results are all gained from the uniformly operated “classical” 100 kW “DUAL FLUID” gasifier at Vienna University of Technology at constant gasification temperatures between 800°C and 810°C. In the “classical” design, the gasification reactor is a bubbling fluidized bed. The composition and ash melting behavior of each feedstock is displayed, as well as the ranges of the product gas compositions generated. Beside the main gaseous product gas components, typical content ranges of dust and char are highlighted. The content and composition of tar in the product gas is discussed. Further it is possible to present gravimetrical and gas chromatography coupled with mass spectrometry measured tar values. Not less than five significant component‐groups of tar will also be outlined for each feedstock. © 2012 American Institute of Chemical Engineers Environ Prog, 2012

CO2 gasification of biogenic fuels in a dual fluidized bed reactor system

“…Therefore, a glass wool filter and washing bottles filled with rapeseed methyl ester (RME) were used to eliminate condensable components like water and tar. A more detailed description of the measurement setup can be found in [10,31].…”

“…Therefore, this research focuses on the reuse of alternative, residual materials and the conversion to high-valuable products by reusing CO 2 within the process. Extensive investigations dealing with fuel variations in the DFB gasification system using steam as gasification agent were already carried out successfully at TU Wien [8][9][10]. However, the gasification of biogenic, low-grade fuels with the use of CO 2 /steam mixtures as gasification agent has not been investigated so far in the DFB reactor system.…”

Analysis of dual fluidized bed gasification integrated system with liquid fuel and electricity products

“…The output syngas (42.6% H 2 , 21.6% CO, 25.1% CO 2 , 10.7% CH 4 ) from DFB reactor is almost the same composition as the literature [8]. For the carbon capture unit and power generation unit, we used pre-made model from Aspen files and industry machine data from GE company to guarantee the accuracy of the models.…”

“…Hofbauer's [8] work also showed the composition and ash melting behaviour of each feedstock, as well as the ranges of the product gas compositions. 40% straw/60% wood blended pellets are chosen as the feedstock in our system and defined as non-conventional components in Aspen Plus based on its ultimate analysis and proximate analysis.…”

“…In this work, parameters of the gasifier model are adjusted to match the characteristics of 100 KW DFB pilot plant at the Vienna University of Technology [8], the composition of bed materials is referred to Stefan's [29] work. Hofbauer's [8] work also showed the composition and ash melting behaviour of each feedstock, as well as the ranges of the product gas compositions.…”