Variation of Feedstock in Dual Fluidized Bed Steam Gasifier

  • Author: ChemistryViews
  • Published: 11 March 2012
  • Copyright: WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
  • Source / Publisher: Envrionmental Progress & Susatinable Energy/AIChE
  • Associated Societies: American Institute of Chemical Engineers (AIChE)
thumbnail image: Variation of Feedstock in Dual Fluidized Bed Steam Gasifier

Dual fluidized bed (DFB) systems are increasingly used for energy conversion technologies such as steam gasification, sorption enhanced reforming (SER), and chemical looping processes (chemical looping combustion/reforming, CLC/CLR). Johannes Schmid and colleagues, Vienna University of Technology, Austria, gasified different fuels like softwood, hardwood, straw/wood blends, and sewage sludge with the 100 kW DUAL FLUID gasifier at their university at constant gasification temperatures between 800 and 810 °C.


The gasifier system showed to be highly flexible with regard to the application of diverse feedstock. The separation between bubbling bed and freeboard in the classical DFB gasification system is responsible for high solids entrainment, if inhomogeneous fuels with high ash contents like dried sewage sludge, or waste wood are used. Fine ash particles are immediately elutriated into the freeboard and entrained from the gasification zone.

Ashes of different sources seem to have positive influences on the in situ conversion of hydrocarbons, similar to the addition of dolomite powder. An extensive gas–solids contact between bed material, ashy fines, additives, and the gaseous phase is crucial to produce a high quality syngas out of various fuels, varying in composition, size distribution, ash content, and physical conditions.

Therefore, a novel dual circulating fluidized bed (DCFB) concept with improved gas–solids interaction, high residence times, and countercurrent effect in the gasification section is under construction at the university. Multistage solids separation systems for coarse and fine particles on each side will be included in the new system.


Article Views: 4372

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

Bookmark and Share

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission. more


CONNECT:

ChemistryViews.org on Facebook

ChemistryViews.org on Twitter ChemistryViews.org on YouTube ChemistryViews.org on LinkedIn Sign up for our free newsletter


A product of ChemPubSoc Europe (16 European Chemical Societies)and Wiley-VCH