Development Of A Pilot Carbon Dioxide Flood In The Rock Creek-Big Injun Field, Roane County, West Virginia

Abstract

Abstract The Rock Creek Field, discovered in 1906, is the site of a pilot carbon dioxide flood designed and installed by Pennzoil Company with financial support from ERDA. Favorable reservoir characteristics and conditions, the inability to successfully stimulate production by conventional waterflooding, and the production by conventional waterflooding, and the fact that nearly 150,000,000 barrels of oil will remain in the reservoir after completion of the low pressure gas recycles now in operation were the main pressure gas recycles now in operation were the main factors responsible for the initial study of miscible fluid displacement by carbon dioxide injection. After laboratory tests indicated the reservoir oil and carbon dioxide to be miscible at a reasonable pressure, the design and installation work for the pilot pressure, the design and installation work for the pilot was initiated. Currently in the water injection or pressure build-up phase, the project has progressed pressure build-up phase, the project has progressed satisfactorily with injection of carbon dioxide scheduled for early 1978. Introduction The Rock Creek Field, which has produced from the Big Injun Sand since 1906, is located in Roane County, West Virginia. During the 71 year life of the field, seven separate projects utilizing three different secondary recovery methods, have been attempted. Low pressure gas recycling, which was implemented in 1935 and continues today, has proven to be the only effective extra recovery mechanism. Waterflooding efforts failed to bank significant quantities of oil with failure attributed to the high connate water saturation, and steamflooding efforts failed due to the low injectivity encountered in the project. Primary recovery by solution-gas drive and project. Primary recovery by solution-gas drive and the secondary recovery by gas recycle account for a total recovery of approximately 20% of the original stock tank oil-in-place (OSTOIP). Therefore, 80% of the OSTOIP will remain after gas recycling. The amount of oil remaining in place coupled with a favorable reservoir temperature, a permeability profile with a high degree of homogeneity, and profile with a high degree of homogeneity, and successful laboratory miscibility tests provided the incentive for a pilot test of a miscible carbon dioxide flood. Pennzoil Company designed, developed, and installed this pilot project with financial assistance from the Energy Research and Development Administration of the United States Government (ERDA). The pilot consists of two contiguous five- spot patterns encompassing approximately ten acres each. These dual five spots are surrounded by thirteen back-up water injection wells drilled as or converted to water injection wells for the sole purpose of containing the injected carbon dioxide. purpose of containing the injected carbon dioxide. Prior to carbon dioxide injection, the reservoir Prior to carbon dioxide injection, the reservoir pressure of 91 psia must be increased to near 1000 pressure of 91 psia must be increased to near 1000 psia. This pressure increase will be accomplished psia. This pressure increase will be accomplished by water injection and monitored by pressure fall-off tests. The project is currently in the water injection or pressure build-up phase. The objectives of this pilot are to determine the oil recovery efficiency of a multiple contact carbon dioxide miscible flood and to define and evaluate operational problems associated with this particular recovery method. The quantitative data particular recovery method. The quantitative data gathered as a result of the installation of the project and the injection performance experienced project and the injection performance experienced thus far conform to expectations. GENERAL FIELD INFORMATION The Rock Creek Field is located in the southeastern portion of Roane County, West Virginia, approximately twenty miles northeast of Charleston, the capitol of West Virginia. The acreage included in the Rock Creek Field makes up the larger portion of the Rock Creek Trend which also includes the Hammack Field to the northeast. The trend itself encompasses 11,200 acres, laterally extends 12.5 miles and ranges between 1.5 and 5 miles in width. (See Figure No. 1) Field History - The discovery well in the Rock Creek Trend was drilled and completed in 1906.