An Assessment of Geological Carbon Storage Options in the Illinois Basin: Validation Phase

Abstract

The Midwest Geological Sequestration Consortium (MGSC) assessed the options for geological carbon dioxide (CO{sub 2}) storage in the 155,400 km{sup 2} (60,000 mi{sup 2}) Illinois Basin, which underlies most of Illinois, western Indiana, and western Kentucky. The region has annual CO{sub 2} emissions of about 265 million metric tonnes (292 million tons), primarily from 122 coal-fired electric generation facilities, some of which burn almost 4.5 million tonnes (5 million tons) of coal per year (U.S. Department of Energy, 2010). Validation Phase (Phase II) field tests gathered pilot data to update the Characterization Phase (Phase I) assessment of options for capture, transportation, and storage of CO{sub 2} emissions in three geological sink types: coal seams, oil fields, and saline reservoirs. Four small-scale field tests were conducted to determine the properties of rock units that control injectivity of CO{sub 2}, assess the total storage resources, examine the security of the overlying rock units that act as seals for the reservoirs, and develop ways to control and measure the safety of injection and storage processes. The MGSC designed field test operational plans for pilot sites based on the site screening process, MVA program needs, the selection of equipment related to CO{sub 2} injection, and design of a data acquisition system. Reservoir modeling, computational simulations, and statistical methods assessed and interpreted data gathered from the field tests. Monitoring, Verification, and Accounting (MVA) programs were established to detect leakage of injected CO{sub 2} and ensure public safety. Public outreach and education remained an important part of the project; meetings and presentations informed public and private regional stakeholders of the results and findings. A miscible (liquid) CO{sub 2} flood pilot project was conducted in the Clore Formation sandstone (Mississippian System, Chesterian Series) at Mumford Hills Field in Posey County, southwestern Indiana, and an immiscible CO{sub 2} flood pilot was conducted in the Jackson sandstone (Mississippian System Big Clifty Sandstone Member) at the Sugar Creek Field in Hopkins County, western Kentucky. Up to 12% incremental oil recovery was estimated based on these pilots. A CO{sub 2} huff puff (HNP) pilot project was conducted in the Cypress Sandstone in the Loudon Field. This pilot was designed to measure and record data that could be used to calibrate a reservoir simulation model. A pilot project at the Tanquary Farms site in Wabash County, southeastern Illinois, tested the potential storage of CO{sub 2} in the Springfield Coal Member of the Carbondale Formation (Pennsylvanian System), in order to gauge the potential for large-scale CO{sub 2} storage and/or enhanced coal bed methane recovery from Illinois Basin coal beds. The pilot results from all four sites showed that CO{sub 2} could be injected into the subsurface without adversely affecting groundwater. Additionally, hydrocarbon production was enhanced, giving further evidence that CO{sub 2} storage in oil reservoirs and coal beds offers an economic advantage. Results from the MVA program at each site indicated that injected CO{sub 2} did not leave the injection zone. Topical reports were completed on the Middle and Late Devonian New Albany Shale and Basin CO{sub 2} emissions. The efficacy of the New Albany Shale as a storage sink could be substantial if low injectivity concerns can be alleviated. CO{sub 2} emissions in the Illinois Basin were projected to be dominated by coal-fired power plants.