Steam‐air blown bubbling fluidized bed biomass gasification (BFBBG): Multi‐scale models and experimental validation
DOI: 10.1002/aic.15666
Abstract
During fluidized bed biomass gasification, complex gas‐solid mixing patterns and numerous chemical and physical phenomena make identification of optimal operating conditions challenging. In this work, a parametric experimental campaign was carried out alongside the development of a coupled reactor network model which successfully integrates the individually validated sub‐models to predict steady‐state reactor performance metrics and outputs. The experiments utilized an integrated gasification system consisting of an externally‐heated, bench‐scale, 4‐in., 5 kWth, fluidized bed steam/air blown gasifier fed with woody biomass equipped with a molecular beam mass spectrometer to directly measure tar species. The operating temperature (750–850°C) and air/fuel equivalence ratio (ER = 0–0.157) were independently varied to isolate their effects. Elevating temperature is shown to improve the char gasification rate and reduce tar concentrations. Air strongly impacts the composition of tar, accelerating the conversion of lighter polycyclic‐aromatic hydrocarbons into soot precursors, while also improving the overall carbon conversion. © 2016 American Institute of Chemical Engineers AIChE J , 63: 1543–1565, 2017
The authors gratefully acknowledge BP for funding this research. Research facilities at the National Renewable Energy Laboratory are supported by the Bioenergy Technology Office and U.S. Department of Energy under contract number DE‐AC36‐08‐GO28308. This research was supported in part by an appointment to the National Energy Technology Laboratory Research Participation Program, sponsored by the U.S. Department of Energy and administered by the Oak Ridge Institute for Science and Education. This contribution was identified by Michael Molnar (Hemlock Semiconductor Group) as the Best Presentation in the session “Fluidization and Fluid‐Particle Systems for Energy and Environmental Applications” of the 2015 AIChE Annual Meeting in Salt Lake City.