Oil & Natural Gas Projects
Exploration and Production Technologies
Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir
Characterization and Horizontal Laterals in a Class I Reservoir-East Binger
The objectives of the project are to demonstrate use of nitrogen as a widely
available, cost-effective and environmentally superior injectant for miscible
floods and to demonstrate the effectiveness of horizontal wellbores in reducing
gas breakthrough and cycling.
Oklahoma City, OK
Nielson & Associates Inc.
Canyon Oil & Gas
International Reservoir Technologies, Inc.
Through the process of evaluating the benefits of horizontal wells in this setting,
a greater understanding of the reservoir flow mechanisms has been obtained,
allowing further development and improved recovery for the field. This geologic
and reservoir setting, combined with the recovery mechanism employed, has proven
to be more appropriate for vertical well development.
Based on results achieved, additional drilling beyond the scope of the original project has been completed. Project development work has added 200-300 barrels of oil per day to field production, roughly doubling production in the project area.
Binger Operations has completed the following:
- Drilled and completed three horizontal and seven vertical wells.
- Converted five wells to injection service.
- Completed modeling and fluid flow characterization work to identify critical fluid flow mechanisms.
- Evaluated over 200 gas samples to monitor gas cycling and the effects of producer-to-injector conversions.
Three horizontal wells have been drilled into the Pennsylvanian Hoxbar formation
of the Eastern Anadarko Basin, where previously only one such well had been
drilled. Drilling difficulties were encountered and overcome. Although these
technologies were not proven to be the most cost-effective for this field-in
large part due to the recovery mechanism employed-they very likely will be the
most cost-effective drilling technique in similar reservoirs with different
recovery mechanisms. The lessons learned here will thus benefit industry, the
State, and the general public through improved oil recovery.
In addition to the development of horizontal drilling practices in this area,
the State and general public also will benefit from the improved understanding
of the nitrogen flood underway in the East Binger Unit. With this improved understanding,
the operator will apply additional knowledge to increase economic oil recovery
from the field, providing monetary benefit to the State and local tax bases.
The public also benefits through improvement in the labor market.
The East Binger (Marchand) Unit has been under miscible gas flood since unitization
in 1977, first with flue gas and then with nitrogen. As with any flood, the
injected fluid finds its way to producing wells (cycling) and must be handled.
This flood was no different, except that the degree of cycling was high for
the level of recovery. Initial review indicated the injected nitrogen was overriding
the oil (gravity segregation) and moving to producers without mixing with and
swelling the oil. It was believed that by placing horizontal producing wells
at the base of the reservoir, miscibility could be improved and cycling reduced.
Project researchers have:
- Improved understanding of flow mechanisms in the Pennsylvanian Hoxbar formation
of the Eastern Anadarko Basin.
- Successfully drilled and completed three horizontal wells in the Pennsylvanian
Hoxbar formation of the Eastern Anadarko Basin, in which only one horizontal
well had previously been drilled.
- Tested the viability of horizontal wells in a tight sandstone formation under
nitrogen miscible flood.
Through the process of implementing the project, it was determined that the
initial assumptions of flow mechanisms in the reservoir were largely incorrect.
Directional flow driven by fracturing-not gravity segregation-appears to be
the primary flow mechanism. With this improved understanding, methods to improve
recovery are being implemented.
Horizontal well development was tested and found to be economically inferior
to vertical well development. Based on the newly identified reservoir flow
mechanisms, the optimal pattern configuration is a line drive, with lines
of injectors and producers oriented in line with the direction of natural
and hydraulic fracturing. As such, horizontal wells should be drilled along
this line. Due to the low rock quality, all wells-including horizontal wells-must
be fracture-stimulated to be productive. The optimal flood pattern configuration,
combined with the need to fracture-stimulate, makes vertical infill well development
economically superior to horizontal infill well development.
Current Status (June 2006)
This project was essentially complete at the end of 2005. Researchers are in the final stages of monitoring results of the work completed. The project initially was planned for completion in April 2005, but no-cost extensions in Budget Periods 1 (+8 months) and 2 (6 months) extended the final completion date to June 30, 2006.
Project Start: April 11, 2000
Project End: June 30, 2006
Anticipated DOE Contribution: $ 3,157,349
Performer Contribution: $ 10,213,824 (77% of total)
NETL - Chandra Nautiyal (firstname.lastname@example.org or 918-699-2021)
Binger - Joe Sinner (email@example.com or 307-587-2445)
Technical reports are available on the project web site: www.eastbingerunit.com.
This illustration shows the performance of the DOE Project Pilot Area. Implementation of the project began in mid-2002 with the conversion to injection (CTI) of well 57-1. New production wells and additional CTIs followed. Pilot area oil production has increased 83 percent, over 200 barrels per day, from the projected base decline. Perhaps more important, nitrogen recycle (nitrogen production divided by injection) has decreased from 70 percent to 40 percent.
The pair of graphs shows a comparison of the performance of new vertical wells with the performance of new horizontal wells. With horizontal wells costing roughly twice the cost of vertical wells, they are not economically justified in this geologic setting with the recovery mechanism employed.
Air separation and compression facility for N2 injection plant at East Binger
Unit, Caddo County, OK
Air separation plant, East Binger Unit, Caddo County, OK.