As construction at Mississippi Power‘s Kemper County energy facility is wrapping up and startup activities are under way, workers have completed packing the plant’s six carbon dioxide (CO2) absorbers and both hydrogen sulfide (H2S) absorbers. Together, these vessels make up the heart of the Kemper plant’s carbon capture and chemical product production capability. The vessels are a focal point both optically and operationally of Kemper, making up the “chemical removal” portion of this unique complex, slated to turn what would otherwise be pollutants into valuable, saleable products before the remaining lignite-derived syngas is used to generate electric power.
“The packing material makes sure we get as much contact between the substances in the gas we want to remove and the solvent that we use,” Charles Powell, gasifier and gas cleanup startup manager said. “It (the packing) makes what would be a concentrated waterfall into a fine drizzle to break up a one million gallon-per-hour flow into an evenly distributed stream inside these vessels.”
Each of the six CO2 scrubbers weighs 550 tons, with the two H2S scrubbers weighing 750 tons each. All of the vessels, each standing more than 200 feet tall, were transported to the Kemper site pre-assembled and then hoisted into place.
“This part of the facility removes substances from the syngas stream that would otherwise be considered a plant emission,” Joe Miller, Kemper startup manager said. “With these processes incorporated into the lignite gasification design, this facility provides a path forward for the continued use of coal in power production.
“This gasification process is capable of using low-rank coal to produce syngas and then cleansing the syngas of pollutants and converting these pollutants into useable products. The cleansed or ‘sweet’ syngas is then used to fuel our gas turbines and make electric power with an environmental footprint that is comparable to a natural gas fired combined cycle facility.”
An estimated $50 million to $100 million in revenue will be generated thanks to this equipment in what’s cumulatively referred to as the Acid Gas Removal (AGR) facility. The sulfuric acid and ammonia will have various industrial and agricultural uses, while the captured carbon will be used by oil companies to force more oil out of aging wells, a process called enhanced oil recovery (EOR).
“This is really the final set-up for our environmental control system – all of the sulfur, carbon dioxide, ammonia and particulate removal equipment is ready for final commissioning and operation,” Miller said.