GILLETTE - Oil production in Wyoming has declined at an annual rate of about 5.4 percent since 1991. But don't count Wyoming's first black gold down and out.

The Wyoming Geological Survey estimates that emerging "enhanced recovery" technologies can still squeeze up to 1.2 billion barrels of oil from the state's aging oil fields, generating as much as $2 billion in state revenues over the next 20 years.

That forecast, and a statewide effort to energize "enhanced oil recovery" efforts, brighten the future even for businessmen in Wyoming's most remote areas, such as Linch in the southeast corner of Johnson County.

"It creates a lot of work. We're lucky that the CO2 (carbon dioxide) line is coming through this way," said Kelly Lohse, owner of L&L Oil Field Service in Linch.

Lohse is among thousands in central and northeast Wyoming who are paying close attention to the work of the University of Wyoming's Enhanced Oil Recovery Institute and other entities that aim to sweep the state's aging oil fields with CO2.

James Steidtmann, director of the Enhanced Oil Recovery Institute, outlined the state's potential for squeezing more oil from its established production fields, while at the same time sequestering CO2 that is a byproduct of natural gas development in the state. The effort also includes capturing the greenhouse gas from other industrial sources in the state.

"A part of our state-mandated mission is to develop economic and efficient ways to separate CO2 from power plant flue gases, and we are funding a research team in UW's Chemical and Petroleum Engineering Department for that work," Steidtmann stated in a UW news release Thursday afternoon.

The 2004 Wyoming Legislature, on the recommendation of a governor's task force, provided $2.4 million to the Enhanced Oil Recovery Institute to expand its research and capabilities for transferring advancing secondary or tertiary recovery technologies into the state.

After primary recovery through conventional drilling, most of the oil remains in the ground - as much as 50 percent of a particular reservoir. Many producers use water flooding to "sweep" additional oil, as well as other technologies that use materials such as brines, salts, surfactants and polymers that help increase the flow of oil to the pumps.

And one of the most efficient ways to sweep oil reservoirs is with CO2, according to Steidtmann. Anadarko Petroleum recently constructed a CO2 pipeline from the LaBarge area to the century-old Salt Creek oil field 45 miles north of Casper, where it aims to squeeze an additional 150 million barrels of oil. The company also hopes to expand its CO2 line to other oil fields in northeast Wyoming, such as the Sussex Field in southern Johnson County, where Lohse's L&L Oil Field Service does business.

Steidtmann said there are also major environmental benefits to enhanced oil recovery through CO2.

"In addition to sequestering CO2, enhanced oil recovery in general has important environmental implications because it takes place in areas previously disturbed during drilling and primary production when power lines and pump jacks were installed," Steidtmann said. "(Enhanced oil recovery) is not conducted in pristine areas, and in fact, many of the power lines and pump jacks can eventually be removed during and after (recovery)."

Star-Tribune energy reporter Dustin Bleizeffer can be reached at (307) 682-3388 or dzeffer@trib.com.