The goal of this project is to increase the deliverability of existing underground gas storage wells by field testing new and improved, cost-effective fracture stimulation technologies that can restore lost injection and withdrawal capability.

Advanced Resources International – project management and research product
NSI Technologies - fracture treatment data analysis

Location:
Arlington, Virginia 22201

There are over 17,000 existing gas storage wells in the U.S. Many of these gas storage wells traditionally exhibit decline in deliverability over several years of production/injection cycling and require some type of remediation to re-establish deliverability. The gas storage industry spends more than 100 million dollars annually trying to revitalize many of these existing storage wells. Excluding new wells or deltapressuring, a recent Gas Research Institute (GRI) report identified fracture technology as having the greatest potential of increasing well deliverability. Yet, fracturing represents only five percent of the revitalization treatments done by the storage industry. New and/or improved existing, cost-effective fracture stimulation technologies and techniques must be demonstrated to the storage industry.

The 27 fracture stimulations carried out during this project verified that these technologies can be safely applied to gas storage wells to increase deliverability. The project also demonstrated the sensitivity of gas storage wells to water and the amount of time required for fracture fluid cleanup. Several stimulation technologies led to significant deliverability improvement indicating that the correct application of fracture stimulations may be the best approach to offset damage.

• Carried out first liquid CO2 sand fracture treatments in storage fields, two of which provided 6-7 fold improvement,
• Enhanced an existing simulator to design and analyze extreme overbalanced (EOB) fracturing, the use of which is now licensed by Halliburton,
• Obtained down-hole treatment records in storage wells for liquid CO2 sand fracs, EOB fracs and propellant fracs,
• Completed a side-by-side comparison of aqueous versus non-aqueous fracturing,
• Demonstrated four new and novel fracture stimulation techniques in eight different fields across the U.S., and
• Collected over 100 multi-point deliverability and pressure transient tests to provide insights into gas storage well performance variability over time that were previously lacking.

The stimulations of two wells that were part of this DOE project were a significant success because they demonstrated that fracture stimulation could be implemented where there was significant concern for height growth into an overlying water formation. The two jobs added an additional 50 million cubic feet per day to the fields' deliverability. The gas storage industry continued to show interest in the findings of this project. In 2001, Kinder Morgan asked the contractor for assistance in conducting two new hydraulic fracture stimulation treatments at Huntsman field - a gas storage facility located in Nebraska. The stimulations, quite similar to the two original DOE project treatments, went as planned and Kinder Morgan was happy with the results.

Work on this project has been completed and a final report written. Four technical reports were written and placed on CD-ROM for public dissemination, with all field data and analyses conducted for the project.

$1,857,911

$300,000

NETL – James Ammer (james.ammer@netl.doe.gov or 304-285-4383)
Advanced Resources International – Scott Reeves (sreeves@adv-res-hou.com or 713-780-0815)

Final Report CD: "New and Novel Fracture Stimulation Technologies for the Revitalization of Existing Gas Storage Wells." May 2000. U.S. Department of Energy/National Energy Technology Laboratory and The Gas Research Institute.