Release Date: January 13, 2006
DOE Announces Commercial Success in Deep Trek Program
Newly-Developed Supercement Seals Leak in Gas Well at Two-Mile Depth
WASHINGTON, DC — A "supercement" developed in the
Department of Energy's Deep Trek program has been commercially applied by
several companies during recent drilling operations to stop seal failures
in wells at depths up to 2 miles.
The Energy Department established Deep Trek in 2002 to address the need for U.S. drillers to go ever deeper—20,000 feet and more—to reach an estimated 125 trillion cubic feet of untapped natural gas. Producing this gas could provide years of domestic production to help meet our Nation's increasing energy needs.
For one Deep Trek project, DOE awarded a $2.5 million cost-shared contract to CSI Technologies LLC (formerly Cementing Solutions, Inc.) of Houston, Texas, to develop a cement capable of withstanding the high pressures and temperatures that exist at those depths.
CSI's challenge was to address the tendency of the cement seals to fail, a problem in establishing deep, long-term production. Located between the casing and the wellbore, cement needs to be able to withstand large changes in pressure in high-temperature environments over the productive life of a well, sometimes more than 30 years. Current Portland cement mixtures have been the preferred material for gas wells, but they are inherently limited in their ability to endure a long life in high-pressure and high-temperature environments, making them less than optimal for deeper wells.
CSI analyzed a variety of Portland and non-Portland cement formulas in its project and developed a supercement sealant, a resin known by the brand name ULTRA SEAL®-R(LIQUID BRIDGE PLUG™). Following a field-scale test on the sealant, CSI found an opportunity for an application in a shallow Gulf of Mexico offshore gas well. When a major offshore operator had difficulties in sealing some of its offshore wells with Portland cement, it applied ULTRA SEAL®-R(LIQUID BRIDGE PLUG™) to successfully seal the wells.
The operator then decided to apply ULTRA SEAL®-R(LIQUID BRIDGE PLUG™) to a deeper problem, a leaking packer set at 10,599 feet inside a 7-inch casing. CSI's product successfully sealed the leak in temperature of over 200°F. Per regulations, this seal passed a pressure test of 1,000 pounds per square inch for 30 minutes.
Following these successful applications, other offshore operators have scheduled jobs to use ULTRA SEAL®-R(LIQUID BRIDGE PLUG™).
CSI expects to further test the performance of this particular supercement, as well as other formulas at high temperatures and pressures. Some of these other formulas will also be tested in wells at shallow depths. The final phase of the project, to begin in early 2006, will involve the application of some formulas in deep wells.
Estimates show that fixing the problems associated with cement failure costs the oil and gas industry about $50 million per year. CSI anticipates that any additional cost of its new formulas will be more than offset by the long-term integrity of the seal and associated reduction in maintenance costs to the operator. Also, it would significantly reduce risks associated with well failure and ecological damage, as well as risks to life and property.
The development of advanced technologies such as CSI's supercement is crucial to the Nation's supply of natural gas. The Energy Department estimates that 12 percent of U.S. natural gas supplies must come from formations deeper than 15,000 feet in the near future, up from 7 percent in 1998. The Deep Trek program supports industry's exploration of and production from these deep gas reservoirs by providing products and technology to safely and economically operate in hot, high-pressure environments.
The National Energy Technology Laboratory manages Deep Trek for the Energy Department's Office of Fossil Energy.
Anna, DOE/NETL, 412-386-4646