In January, the US Department of Energy announced new grants for 10 microhole technology projects to be managed by the Office of Fossil Energy's National Energy Technology Laboratory (NETL).
Total value of the projects is nearly $14.5 million, with the DOE providing $7.7 million and industry partners contributing $6.8 million. The petroleum industry will assume about 47% of the cost, demonstrating its strong commitment to these advanced technologies and suggesting strong future support for their commercialization and adoption.
- Geoprober Drilling Inc., Houston. This project calls for drilling three wells with an innovative composite coiled-tubing drilling system. The aim is to confirm the capability of drilling low-cost, shallow slim or microhole exploration wells in water depths ranging up to 10,000 ft.
Cost savings, projected at 59% over that for conventional wells, would come by use of a smaller drilling vessel and by elimination of the need to deploy and retrieve a large riser—essentially a large-diameter pipe that is the extension of the wellbore in deep waters (DOE share: $1 million; project duration: 12 months).
- Gas Technology Institute, Des Plaines, Ill. This project entails a proposal to field test a next-generation microhole coiled-tubing rig. The MOXIE experimental rig was fabricated by Coiled Tubing Solutions, (Dallas, specifically for coiled tubing and microhole drilling to 5,000 ft subsurface. First deployed for initial testing in a Kansas gas field last year, the rig was able to drill 280–400 fph.
GTI will assess field tests and lead a technology-transfer program. Expected benefits from this technology include 28–38% lower drilling costs per well, decreased waste generation, reduced environmental impacts, and increased production from existing fields (DOE share: $1 million; project duration: 12 months).
- Confluent Filtration Systems LLC, Houston. Researchers will seek to develop a revolutionary elastic-phase, self-expanding tubular technology called CFEX. CFS's goal is to develop self-expanding well casings to any diameter, leading to improved methods and feasibility of monobore drilling and well construction (DOE share: $1 million; project duration: 36 months).
- Tempress Technologies Inc., Kent, Wash. The goal of this project is to develop a small, mechanically assisted, high-pressure water-jet drilling tool. A downhole intensifier would boost the pressure that can be delivered by coiled tubing, maximizing drilling rates. That in turn would overcome the limited reliability, power, and torque of small-diameter drill motors, a major hurdle for microhole drilling reliability (DOE share: $800,000; project duration: 24 months).
- CTES LP, Conroe, Tex. Researchers will focus on improving the performance and reliability of microhole coiled-tubing drilling bottomhole assemblies while reducing the cost and complexity associated with drilling inclined or horizontal well sections deeper than 2,000 ft. This would be accomplished by an induction of vibration along the coiled-tubing drill string in order to eliminate the need for a downhole drilling tractor to mitigate friction.
The goal is to enable operators to economically use coiled tubing to drill microhole sections greater than 3,000 ft in horizontal wells, which typically offer production rates two to three times greater than those for vertical wells (DOE share: $700,000; project duration: 24 months).
- Technology International Inc., Kingwood, Tex. This project entails developing and testing an effective downhole drive mechanism and a novel drill bit for drilling with coiled tubing.
The high-power turbodrill will deliver efficient power at relatively high revolutions per minute and low bit weight. The more durable drill bit will employ high-temperature cutters that can drill hard and abrasive rock in 31/2-in. boreholes (DOE share: $800,000; project duration: 24 months).
*Ultima Labs Inc., Houston. This project is intended to combine existing technologies for measurement-while-drilling (MWD) and logging-while-drilling (LWD) into an integrated, inexpensive measurement system to facilitate low-cost coiled tubing drilling of small-diameter (31/2 in.) wells at depths shallower than 5,000 ft.
MWD and LWD, while costly, have become crucial tools for oil and gas operators in sustaining drilling and well-completion efficiencies. Two prototypes are to be delivered, ready for field testing (DOE share: $800,000; project duration: 36 months).
- Baker Hughes Oilfield Operations Inc., Houston. Researchers will seek to provide a critical tool essential for an effective modular coiled-tubing drilling system: a wireless system to help steer drilling in a microbore. The use of such "smart" wells—which have grown in acceptance by industry because of their inherent efficiencies and cost savings—might otherwise limit microholes to a smaller range of locations and reservoir types.
Plans call for developing a downhole bidirectional communication and power module and a surface coiled-tubing communication link (DOE share: $800,000; project duration: 24 months).
- Gas Technology Institute. An important goal for advancing coiled-tubing drilling of microholes is to improve the rate of penetration by 25–60%, thereby cutting drilling costs by up to 40%. This project entails designing, developing, and evaluating a counter-rotating motor drilling system ideally suited for reducing costs associated with drilling wells targeting unconventional gas.
By concentrating the weight on the drill bit in a smaller area and by addressing the limited torque on a coiled-tubing drill string, this research would increase the effectiveness of coiled-tubing drilling (DOE share: $600,000; project duration: 24 months).
- Confluent Filtration Systems LLC. Another major concern for microhole drillers is the damage caused to casing from sand that infiltrates the drill string. This is especially problematic in small-diameter wellbores. Accordingly, there is a great need for downhole sand screens that are versatile and robust while being suited for a variety of drilling environments.
This project is designed to prove and develop a concept for a self-expanding, high-flow sand screen that could be constructed from a wide range of materials. Plans call for ultimately deploying the technology in a demonstration well (DOE share: $200,000; project duration: 24 months).