Publications

CO2– EOR has been an important part of the oil industry for well over 50 years. The firstCO2 flood in Wyoming (1986) continues today at Lost Soldier/Wertz Fields (Baroil). Since 1986 incremental oil production from CO2- EOR is approximately 150 million barrels with severance tax revenue to the State of over $400 million ($50/bbl oil price).

The CO2 used to recover oil is part of a “closed-loop-system”. The CO2 is injected, separated from the produced oil, recycled, and reinjected. Through the life of the project, all CO2 injected (purchased and recycled) is stored in the reservoir.

CO2 is an expensive commodity for EOR with an approximate cost of ~ 2% of oil price (WTI)/MCF. Some floods in Wyoming have purchased well over 200 MMCF/Day - over $300,000/day just for CO2.

A successful reservoir model requires the right kinds of data as well as accurate data.

3D reservoir modeling is useful for petroleum reservoir production forecasting and for developing a methodology to optimize recovery.  Reservoir modeling requires a commitment to assimilating accurate information in the proper format and this document outlines the requirements, descriptions and importance of key data.

The rock layers surrounding Alcova Lake are not only breathtaking to see, they are also windows to a portion of the earth’s history. This guidebook hopes to introduce anyone interested to a brief explanation about what the geology is revealing.

EORI shares this guidebook as part of its commitment to facilitating technology transfer through publications and oral presentations.

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At Rozet Field, the lack of abundant core analyses or modern logs necessitates the adoption of more assumptions than usual in order to estimate OOIP and remaining recoverable reserves. Two different methods for calculating the recovery efficiency of the waterflood were applied withinnine 5-spot patterns resulting in maximum rates of 40% and 30% respectively. Average recovery factors in the combined 5-spot patterns are 27.5% and 24.4% respectively. Both values indicate the waterflood is probably not as effective as it could have been when compared to similar fields producing from the Muddy Formation.

The calculated OOIP for the Muddy Formation at Rozet is about 74.7 million barrels, of which a little over 19 million barrels have been recovered. The recovery factor for the field is then about 25.5%. If a 40% recovery factor is achievable with an efficient waterflood, then the remaining recoverable oil reserves from the Muddy Formation at Rozet Field are approximately 10.8 million barrels. This magnitude of a target should warrant further investment in improved and enhanced recovery methods there.

At nearby Windmill Field, secondary recovery has yet to be implemented in the Muddy reservoir. Wireline log suites containing porosity logs in this field enable more confidence in the geologic mapping and OOIP calculations than at Rozet. Cumulative oil production there is 677,735 barrels, resulting in a recovery factor of about 14.8%. Assuming the clay content does not vary significantly from that observed at the adjacent Rozet Field, a well-designed waterflood should be effective at increasing production in Windmill Field. If a recovery factor of 40% could be achieved by implementing secondary recovery efforts there, it could result in the production of an additional 1,157,465 barrels of oil.

• Nine different reservoirs in seven fields have employed fieldwide CO2 EOR in Wyoming.
• Between 2010 and 2020, incremental oil recovery from the nine CO2 EOR projects accounted for over 10% of Wyoming’s total oil production.
• Wyoming is not constrained by CO2 sources that can be used for EOR projects.
• Wyoming is also not constrained by fields potentially amenable to CO2 EOR.
• Wyoming is not constrained by pipeline capacity for additional CO2 transport, but is hampered by the existing pipeline system not reaching many of the best-potential fields, especially in the Big Horn Basin.
• The most successful CO2 floods resulted from proper reservoir characterization and associated optimized project design. Wyoming has seen incremental oil recovery from individual CO2 EOR projects as high as 18% of OOIP and volumes as high as 30 million barrels.
• Where net CO2 efficiencies could be calculated, CO2 efficiency is as low as 6 Mcf/bbl of incremental oil recovered, which compares very favorably to other successful projects around the world.

The results of EORI’s sponsored test of Viper Drill’s ultrashort radius (USR) drilling technology could be a sound investment for Wyoming operators.

Ultrashort radius drilling technology was successfully tested in two wells (an injector and a producer) at Thompson Creek Field in northeastern Wyoming that were experiencing problems due to near-wellbore formation damage.  Both wells exhibited marked improvement in performance after the drilling of four short (<30’ long) USR laterals from each borehole, indicating that this method should be considered in other wells throughout the state that are experiencing similar problems.

Reservoir characterization and predictive modeling has provided options for enhancing production in a recently discovered trend in the Muddy Formation near Hirsch Field, in northeastern Campbell County, Wyoming. This report outlines the procedures followed to develop a detailed 3-D geologic model of the Muddy Formation in the Hirsch area and provides the results of simulations run on 73 different scenarios for developing the reservoir. This study can serve as a template for operators interested in exploring possible ways to improve production in their own fields.

Evaluating the effectiveness of products and/or methods that might improve oil and gas production in Wyoming is one of the functions of the Enhanced Oil Recovery Institute (EORI). As part of that effort, EORI sponsored an evaluation of a novel product that reportedly could help reduce the detrimental effects of paraffin precipitation and deposition in oil wells.

This novel product is produced from recycled tires and is under development by a clean-tech company that converts scrap rubber materials into several beneficial products. Although analyses have shown that this product in its current form does contain a significant quantity of aromatic solvents that may act either as inhibitors of paraffin wax deposition or as a paraffin solvent, tests using the novel, tire-recycled oil (TRO) product on three different paraffinic oils from Wyoming oil fields showed that the concentrations of these solvents in the product are insufficient to provide substantial benefits for that purpose.

Advanced Resources International has published the U.S. CO2 Enhanced Oil Recovery Survey for end-of-year 2020.

The Enhanced Oil Recovery Institute’s Acting Director, Lon Whitman, is a contributor to an important and anticipated publication of the U.S. CO2 Enhanced Oil Recovery Survey.

The purpose of this updated survey is to provide a comprehensive status report of the 142 active CO2-EOR projects in the U.S., including enhanced production totals, reservoir characteristics, and other project parameters.

Throughout a challenging year, incremental oil production from CO2-EOR declined about 8% to 273,000 barrels per day -- this total is on par with the overall decline in U.S. crude oil production in 2020.

Despite a significant decrease in the volumes of CO2 available for injection and storage the CO2-EOR industry was able to maintain production by recycling CO2 rather than having to shut in wells. This strategy shows the resiliency of CO2-EOR during challenging economic conditions, and further supports the viability of this method as a means of storing CO2 and producing lower carbon intensity oil in the U.S.

Thermal maturity, the degree to which the total organic carbon in a formation has been transformed from kerogen to producible hydrocarbons due to heat and pressure, is an important measure for not just the quality of a source rock, but also helps for delineating areas more favorable for unconventional drilling. EORI’s report of thermal maturity of the Mowry Shale in the Powder River Basin provides a detailed map based on a large public T_max data set.

Key observations include:

• Nearly all of the Mowry deeper than 8000’ currently generates hydrocarbons
• The basin axis has shifted slightly westward since the Mowry began generating hydrocarbons
• The Mowry 8000’ line plays an important role in demarcating the over-pressured Mowry and related clay diagenesis.
• The maximum maturity levels in the Mowry are in the “wet gas” stage

Is CCUS Feasible in WY? Wyoming’s Unique Position in the World’s CCUS Arena - The Cowboy Unicorn.

The primary objective of the study is to assess the possible implications to GHG emissions associated with this proposed ban and to do so, estimate the drilling and production losses from policies to restrict oil and gas development on federal lands. From that estimate, the emissions impacts are assessed by examining the difference in emissions associated with possible makeup production, compared to the production loss resulting from the ban, or from higher natural gas drilling levels that may be required to make up for lost supplies.

This study estimates the investment and production losses from policies to restrict oil and gas development on federal lands. The first policy is a moratorium on all new federal leases. The second involves an outright drilling ban on all onshore federal lands. The scope of this inquiry includes a study region that includes eight states: Wyoming, New Mexico, Colorado, Utah, Montana, North Dakota, California, and Alaska. These lost opportunities are estimated by first projecting how drilling and production activity is likely to evolve from 2021 through 2040 and then identifying what portion would be affected by the two policies.

In their study, Open Water Capital Partners highlights solutions to mitigate the long-term effects of a sustained downturn in coal, oil and natural gas and introduces strategies to limit the downturn’s impact while supporting Wyoming’s energy industry.

Open Water Capital Partners introduce strategies to curtail this impact to Wyoming’s economy with a three-pronged approach providing “immediate financial relief to operators, access to longer term liquidity amidst the volatility, and establishes a platform to more broadly diversify state revenue streams. 

Wyoming, perhaps more than any other state, is dependent on revenues generated from the development and sales of minerals within its borders and has a vested interest in ensuring that its resources are properly and efficiently exploited. Maximizing the efficiency of oil and gas production in Wyoming is one of the primary goals of the Enhanced Oil Recovery Institute (EORI). Potential methods or practices that can improve or enhance the recovery efficiency of oil and gas production in the state are of paramount interest. Likewise, those policies or practices that hinder such efforts are also important to discuss.

Wyoming has nearly one billion barrels of proved oil reserves, a significant portion of which is still on primary production. Assessing the potential for secondary recovery from current oil fields is always a daunting task and requires evaluations regarding whether any given field will respond favorably to secondary recovery efforts.

This paper makes general assumptions regarding the feasibility of using a water flood to enhance oil recovery in a field based on publicly available data. The conclusions resulting from these assumptions are meant to be a guideline for the potential of future water flooding and are not meant to provide detailed evaluations of any given field’s ultimate recovery.