DOE - Fossil Energy Techline - Issued on:  July 16, 1996

DOE to Assist Small Producers Adapt "Gas Repressurization" to Boost U.S. Oil Production


Bartlesville, OK - Injecting natural gas or other gases into an oil reservoir to force additional crude oil to production wells is a common practice of major oil companies and large independent producers. But rarely have smaller companies operating in many of the Nation's marginal oil fields adopted the procedure. Economic and technical uncertainties have been the stumbling blocks.

Now, the Department of Energy (DOE) wants to change this and give the small, independent producer a potentially promising option for prolonging the productive life of oil fields that are on the verge of being abandoned.

DOE said today that it has selected four projects, all with small independent oil producers, to carry out field experiments to test scaled-down "gas repressurization" processes specially adapted for smaller reservoirs.

The four projects will be carried out by:

The four companies will be required to at least match the Federal funding with either cash or in-kind contributions. DOE will provide $521,000 for the projects. BDM-Oklahoma, Inc., DOE's operator for the National Institute for Petroleum and Energy Research, which selected the projects, will provide engineering and geological assistance and will monitor the projects through June 1997. By then the projects, if successful, should begin showing significant additional oil production.

Adapting gas repressurization technology to small scale operations involves considerable technical and economic challenges. The process involves injecting natural gas (methane), nitrogen, or flue gases from aboveground combustion processes into a reservoir. The technique maintains or rebuilds the pressure in the reservoir that is often lost during years of primary production.

For many oil fields in the country, both large and small, pressure maintenance or repressurization can prolong the productive life of the field's reservoirs. But what is routine and economical for large operations is often not so straightforward for smaller, marginal fields.

Processes that make financial sense when applied on a large scale must be significantly redesigned to be economically feasible for smaller reservoirs. Before repressurization is common within the independent oil industry -- which now drills 85% of all of the wells in the United States -- companies must be confident that the redesigned approaches are technically reliable and financially sound.

The four DOE cosponsored projects are intended to help build this confidence level. Each of the four companies has committed to conveying the lessons learned from the projects to other independent producers. Field tours and technical presentations by the producers will be included in each project to give other companies an opportunity to evaluate their properties and the economics of implementing gas repressurization.

In return for receiving Federal cost-sharing, the companies will provide detailed accounts on: why a specific gas repressurization project was chosen, why the process is compatible with the reservoir architecture and the factors that control oil recovery, the design of the project, its startup, its operating problems, the oil production response, and the economics of the project.

The four projects will become part of DOE's National Oil Program, overseen by the Bartlesville Project Office. The program has been substantially reoriented in recent years in an effort to help fill the technological gaps being created by the departure of major oil companies from the United States. Increasingly, smaller independent companies -- typically with 10 or fewer fulltime employees -- are becoming the principal players in developing America's oil and gas resources.

The following describes the four projects in more detail:

Robert Klaeger -- DOE will provide $133,000 for a cyclic ("huff `n puff") natural gas project to recover 18 degree API gravity oil from the Olmos sandstone, Taylor-Ina field in Medina County, TX. The project is the most challenging of the four projects. Several enhanced oil recovery methods have been tried and failed because clays in the reservoir have swelled and blocked the flow of fluids through the reservoir rock. Natural gas injection could overcome the reservoir's sensitivity to fluids. In the project, several wells will be reworked, additional wells are to be drilled, and gas lines will be installed. The project manager is Joe H. Klaeger, 1209 Lakeshore Drive, Marble Falls, TX 78654, telephone: 210-693-6569.

Driver Production, Inc. -- DOE will fund $115,000 for a flue gas injection project to recover 30o API gravity oil on a "five-spot pattern" (meaning that four injection wells surround a central producing well) in a Dutcher sandstone reservoir in the East Edna field in Okmulgee County, OK (near Slick, OK). A flue gas generator will be built and should begin operating this summer. The project manager is John Godwin, Driver Production, P.O. Box 696, 1616 East 36th Street, Okmulgee, OK 74447, telephone: 918-756-7498.

A.R.& R. -- DOE will provide $140,000 for a project to repressurize a Weiser sandstone oil reservoir using natural gas obtained from shallower coal beds. The project will be located in the Sorghum Hollow field in Chautauqua County, KS (near Hale, KS). At the project site, one well is already producing methane from a coal bed. A second coal bed methane well will be drilled, and oil wells that were shut in in 1993 will be reopened and reworked. The operator expects to begin injecting gas from the existing coal bed well into the oil reservoir this summer and from the second coal bed methane well by the end of the year. The program manager is Andy Park, A.R.& R. Ltd., Rural Route 2, Box 73, Elk City, KS 67344, telephone: 316-673-8231.

Hydrogen Generation Inc.-- DOE will fund $133,000 for a flue gas drive project to recover 43 degree API gravity oil from the Chipmonk sand in the Allegany field in Cattaraugus County, NY (near Allegany, NY). The field, which is near the Pennsylvania/New York state line, has been the site for several unsuccessful enhanced oil recovery projects by both small operators and major oil producers. Most of the field's wells were drilled prior to World War II, and the field has been waterflooded in an attempt to produce additional oil. The operator proposes to build a flue-gas generator, rework several wells, and begin injecting flue gas this summer. The project manager is Don Benson, Hydrocarbon Generation, 4683 Birch Run Road, Allegany, NY 14706, telephone: 716-372-8581, fax: 716-372-8645.

DOE Information Contacts:
Herb Tiedemann, Bartlesville Project Office, 918-337-4293; e-mail: htiedema@bpo.gov

David K. Olsen, BDM-Oklahoma, National Institute for Petroleum and Energy Research, 918-337-4479