The Gasification and Syngas Cleaning Process Development Unit is operated by the Bioeconomy Institute. Contact Ryan Smith at rgsmith@iastate.edu or (515) 294-6244 or Lysle Whitmer at lwhitmer@iastate.edu or (515) 296-6309 for availability.

Gasification Reactor

The 20 kg/h fluidized bed gasification reactor (gasfier) can be operated at pressures up to 20 psig. It is specially designed to be adiabatic in order to accurately simulate the behavior of larger industrial gasifiers. The gasifier is operated at 850C using either air or steam/oxygen mix as a fluidizing agent. High temperatures within the reactor result in rapid chemical reactions, yielding a producer gas stream composed mostly of lower molecular weight compounds (H₂, CO, CO₂, CH₄, and H₂O). The primary gasification feedstock is switchgrass, but other possibilities include corn stover, wood fiber, corn fiber, and red oak.

Syngas Cleaning System

The gasification process also generates minor amounts of higher molecular weight components (tars), contaminant compounds (H₂S, NH₃, HCl, etc.), and char. These components inhibit downstream applications by fouling pipes or deactivating catalysts used in fuels production. Removing them is necessary to apply the gas stream in multiple applications from power generation in turbines to liquid fuels production via Fischer-Tropsch synthesis.

The cleaning system downstream of the gasifier removes the contaminants using several techniques. Tar and residual particulate matter are removed by oil scrubbing. Sulfur removal is performed through fixed-bed adsorption. Water scrubbing removes ammonia via absorption.