EOR II pilot — Mumford Hills Oil Field, Indiana

This miscible liquid CO2 pilot is designed to inject CO2 into a prevalent Illinois Basin oil-bearing interval (or equivalent) to directly measure CO2 sequestration mass, enhanced oil recovery, and CO2 injection rate. The Clore Formation, an oil-bearing interval similar to the Cypress Sandstone, was chosen as the target formation. Numerical modeling will be used to assess EOR and sequestration at large scale and update Phase I CO2 storage resource estimates for oil reservoirs.

The injection formation is 1,900-ft deep, wedges of fine-grained sandstone, thickness 15–20 ft. Average permeability of 150 mD, 19% porosity, good communication throughout, channel type environment.

  • Inject CO2 as a liquid into an existing oil well converted to a CO2 injection well
  • Produce fluids from four wells surrounding the injector in an inverted 5-spot pattern, returning abandoned well to complete production pattern
  • Maintain reservoir pressure with peripheral water injection, a balance of simultaneous peripheral water flood and CO2 flood
  • Eliminate rod pumps and tubing, and reduced electrical costs in CO2 EOR flood by flowing wells to surface
  • Metered and monitored CO2, hydrocarbon gas, oil, and water production

Project status:
  • Completed

CO2 injection results:
  • 6,950 tons cumulative injection
  • 20–35 tons/day injection rate

  • Direct pilot measurements
    • Estimated IOR is 2,590 bbl oil
    • Esitmated CO2 EOR 2,045 bbl
    • Approximately 0.5% of the injected CO2 was produced at the surface through September 11, 2011; consequently, 99.5% of the injected CO2 was stored
  • Fullfield projections:
    • Estimated potential CO2 storage is 213,000 to 305,200 tons
    • Model results suggest that full-field CO2 injection for 20 years could have 12% oil recovery, or 170,000 stb
  • No effects of CO2 injection detected outside of the injection zone

Monitoring, verification, and accounting:
  • Conducted baseline, injection, and post-injection monitoring, including continuous in-zone pressure and temperature, monthly brine chemistry of the injection formation, cased-hole logging, and shallow groundwater quality to assess any CO2 related changes
  • Monitored brine and shallow groundwater quality through August 2011, one year after CO2 injection termination
  • Conducted reservoir, geochemical, and groundwater flow modeling to verify operational and field efforts
  • Hydrogeologic flow model developed for site indicates shallow groundwater flow to northwest toward Black River
  • Detected no CO2 leakage outside of the intended reservoir; analysis of brine and gas chemistry made it possible to track plume migration and infer geochemical reactions and trapping of CO2

Midwest Geological Sequestration Consortium
Midwest Geological Sequestration Consortium
Advanced Energy
Technology Initiative

University of Illinois
615 E. Peabody Dr.
Champaign, IL 61820