Reducing Aerosol in Flue Gas

Solvent-based post-combustion CO2 capture (PCC) technology remains one of the leading methods to combat global CO2 emissions produced from large-scale coal-fired power production.

However, high concentrations of aerosol particles in the flue gas upstream of solvent-based PCC plants can cause significantly high solvent loss rates in the treated gas if no aerosol mitigation measures are implemented.

When very high concentrations of aerosol particles lead to elevated solvent emissions in the treated gas exiting the CO2 absorber, high solvent make-up rates are needed to combat the loss of solvent to efficiently and safely operate a PCC plant. This can lead to prohibitively high operating costs and extremely difficult logistics challenges.

ISTC researchers Vinod Patel and Kevin OBrien received approximately $3 million from Department of Energy in spring 2018 to collaborate with engineers at Linde, LLC and Washington University, St. Louis, in validating two innovative technologies that have the potential to significantly reduce flue gas aerosol concentrations. These include a high-velocity water injection spray concept and an electrostatic precipitator, which are Linde and Washington University innovations, respectively.

The technologies will be tested at the University of Illinois Abbott Power Plant, and the results will be used as a benchmark for the performance and cost of these technologies to compare with the existing options for pretreating coal-based flue gas for aerosol mitigation.

“We came across this aerosol problem in Phase I of a two-phase project we performed on carbon capture at coal-fired power plants,” said Patel, ISTC chemical engineer. “We don’t want the solvent to go into the aerosol or into the atmosphere. It is important to address this issue before we scale up the project to a larger facility, which is our goal in the later project phases.”