Technology Demonstration of Multi-Species (CO₂, SO₂, NO₂, & PM) Capture

Post-combustion capture of carbon dioxide usually requires other upstream pollutant capture systems such as selective catalytic reduction for NOx, flue gas desulfurization, electrostatic precipitators, etc (Dziejarski et al. (2023)). Traditional carbon capture technologies cannot be deployed at point emission sources that do not have these systems and use fuels containing sulfur (e.g., heavy fuel oil, sour gas, etc.). A novel pollutant capture system is being developed at KAUST that eliminates this limitation. A Cryogenic Carbon and Sulfur Capture (CCSC) technology is developed in partnership with Sustainable Energy Solutions (SES, part of Chart Industries). This technology focuses on post-combustion CO₂ capture along with SO₂, NO₂, and other Particulate Matter (PM) pollutants. CCSC is modular in design and mounted on a 15-meter-long trailer. The multi-species co-capture system is mounted in the central section of the trailer and includes a separate control room and gas storage room on either end of the trailer. This trailer-mounted CCSC system has a nominal capacity of capturing 0.25 ton of CO₂/day. This CCSC process cools exhaust flue gases below the desublimating temperatures of CO₂ (~−130°C) where CO₂ solidifies out of the flue gas. This separation process is done by spraying isopentane as a contact liquid into an upward-moving flue gas. CO₂ freezes into the contact liquid and ultimately flows out as a slurry. The contact liquid is regenerated via screwpress, and then the interstitial liquid is recovered via distillation. An additional column is necessary for the separation of a third species SO₂. The main objective of this trailer rig is to serve as a technology and IP development platform to cocapture multiple pollutants all using a single technology. The trailer rig is designed to be flue gas agnostic and finds applications in many facilities. Even though the system is currently optimized for the most probable site which is a heavy fuel oil (HFO) fired steam power plant, it can easily be adapted to shipboard carbon capture and co-capture of other pollutants more prominent from marine applications. A wetted-wire patented technology from KAUST (Wagstaff et al. (2022)) already shows promise for shipboard heat and mass transfer.