Carbon Dioxide Injection Begins at Fully Integrated Coal-Fired CCS Project

Injection of carbon dioxide began last week at one of the world’s first fully integrated coal-fired carbon capture, transportation, and geologic storage projects. The "Anthropogenic Test" conducted by the Southeast Regional Carbon Sequestration Partnership (SECARB) transports carbon dioxide via a 12-mile pipeline from a 25-MW post-combustion carbon capture facility at Southern Co.’s 2,657-MW Plant Barry in Bucks, Ala., and sequesters it within a saline Paluxy Formation at the nearby Citronelle Oil Field operated by Denbury Resources.

The 25-MW coal-fired carbon capture facility at Plant Barry, owned and operated by Southern Co. subsidiary Alabama Power, uses Mitsubishi Heavy Industries’ (MHI’s) KM CDR Process. Launched in August 2011, the facility is designed to capture nearly 150,000 tons of CO2 annually (500 tons/day) at a CO2 capture rate of over 90%. MHI’s KM CDR Process technology uses an advanced solvent called KS-1 to capture the CO2 from a flue gas stack. The flue gas is directed to the KM CDR Process, where the KS-1 solvent reacts with and captures the CO2. CO2 can then be separated from the KS-1 and compressed for pipeline transport.

SECARB, one of seven partnerships in the Department of Energy’s (DOE’s) Regional Carbon Sequestration Program, said it has identified a "series of thick, regionally extensive saline formations with high-quality seals" within the Gulf Coastal region. It chose the Cretaceous-age Paluxy Formation sandstone, sited just 12 miles west of Plant Barry, for the anthropogenic carbon storage test because the storage site is located within the Citronelle Dome geologic structure, which provides "secure four-way closure free of faults or fracture zones," it said.

The Paluxy Formation itself is a major reservoir containing saline water, which occurs at a depth of 3,000 to 3,400 meters. It is also overlain by multiple geologic confining units that "serve as vertical flow barriers and will prevent CO2 from escaping from the storage reservoir," the group said.

Last year, SECARB built the pipeline to link the Plant Barry capture system to the formation. Carbon dioxide injection is now expected to take place over two years at a rate of up to 500 metric tons per day.

SECARB’s stated research objectives for the project are to test the CO2 flow, storage, and trapping mechanisms of the Paluxy Formation; evaluate injection and storage capacity of the saline reservoir; and evaluate the integration of power plant CO2 capture, transportation, injection, and long-term geologic storage. It will also seek to understand how the saline reservoir’s internal architecture (the interplay between the reservoir flow units, seals, and baffles) can be effectively used to maximize available CO2 storage capacity and minimize the  areal extent of the CO2 plume; test commercially available, but not yet utilized, “off-the-shelf” and experimental CO2 monitoring technologies; and evaluate the effect of anthropogenic CO2 captured from a coal-fired power plant on the geochemistry of a saline reservoir.

The DOE has provided nearly $77 million for the project—about 69% of the $111 million total. Injection operations are slated to end in 2014, and post-injection modeling, verification, and accounting efforts are expected to be wrapped up in 2017. The site will be then closed; the wells will either be plugged and abandoned, according to state regulations, or re-permitted for CO2-enhanced oil recovery and CO2 storage operations.

SECARB’s Anthropogenic Test is led by the Southern States Energy Board in partnership with the Electric Power Research Institute, Southern Company, Alabama Power Co., Denbury Resources Inc., Advanced Resources International Inc., and other experts.

Sources: POWERnews, DOE, SECARB

—Sonal Patel, Senior Writer (@POWERmagazine)