DOE/METC/C-96/72 15

DOE/Fossil Energy's Drilling, Completion, and Stimulation RD&D: A Technologies/Products Overview

Authors: John R. Duda Albert B. Yost

Conference Title: Society of Petroleum Engineers' 1995 Eastern Regional Conference and Exhibition

Conference Location: Morgantown, West Virginia

Conference Dates: September 18-20, 1995

Conference Sponsor: Society of Petroleum Engineers

DISCLAIMER

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any Iegal liability or responsibility for the accuracy, completcness, or usefulness of any information. apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

This report has been reproduced directly from the best available copy.

Available to DOE and DOE contractors from the Office of Scientific and Technical Information, 175 Oak Ridge Turnpike. Oak Ridge, TN 37831; prices available at (615) 576-8401.

Available to the public from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161; phone orders accepted at (703) 4874650.

SPE 30993

DOEIFossil Energy's Drilling, Completion, and Stimulation RD&D: A Technologies/Products Overview John R. Duda, SPE, and Albert B. Yost 11, SPE, U.S. Department of Energy, Morgantown Energy Technology Center

This papu IIB prepbred Cor presentation at in Horg.n)cum. West Vrprw. 18-20 seplember 1995.

Thii lwper was S&URY lor presentation by an SPE Program Cornminee following review of informatm um~nad n an aWraC( submiied by the author(s). Contents of the paper. as presenwd, have nu bm revtewed by the Society of Petroleum Engineers and are subject to an- r e d m by me amor@) The matertal. as presented, does not necessarily rdW any position of me ol psnolsvn Engmews. ils oKkers. or members. Papers presented at SPE meetings are subpa 10 puWcatnn r- by Ed~twial h m i n e e s of the Society d Petroleum Engineers. WnceLibn~n. WE. P O Box 833836. Riim.TX 75083-3836. U.S.A. faxO1-214-952-9435.

Eastern Regional Conference and E&~ibiion heM

Abstract An overview of natural gas drilling, completion, and stimulation RD&D sponsored by the U.S. Department of Energy is reported in this paper. Development of high rate-of-penetration drilling systems and underbalanced drilling technologies are detailed among other RD&D activities. The overview serves as a technology transfer medium and is intended to accelerate the deployment of the products and technologies described.

Introduction The United States (U.S.) Department of Energy (DOE) through the Ofice of Fossil Energy (FE) sponsors natural gas drilling research, development, and demonstrations (RD&D) as part of its overall mission. In part, that mission calls for the Department to lead in achieving efficiency in energy use, diversity in energy sources, a more productive and competitive economy, improved environmental quality, and a secure national defense.' All natural gas supply activities support the Department's strategies* and the Domestic Natural Gas and Oil Initiative?

Fossil Energy focuses its RD&D efforts to stimulate sustain- able development and utilization of the Nation's fossil fuel resources and to assure an ample, secure, clean, and low cost domestic supply of energy! The Morgantown. WV, field office has primary responsible for implementing the natural gas supply program. Fossil energy RD&D at the Morgantown site is managed through "business ~ectors."~ The RD&D described herein is affiliated with the fuels resources suppIy business sector.

Within the business sectors at the Morgantown Energy Tech- nology Center, individual project RD&D is organized by product

line. Product lines comprising the fuels resources supply busi- ness sector include:

Resources and reserves, Drilling, completion, & stimulation, and Development of low-permeability formations.

This writing is intended to provide the reader with an overview of the projects within the drilling, completion, and stimulation (DCS) product line. It also updates an earlier synopsis of the product line! To provide an overall context, the DCS product area goal is to

develop and test drilling, completion, and stimulation products and technologies which reduce cost and/or improve process eficiericies ........ ultimately leading to a lower unit cost of natural gas.

Fig. 1 shows a simple diagram illustrating the "hierarchy" of project implementation.

DOE/Morgantown recognizes the importance of directing RD&D to relatively higher impact areas in terms of cost, safety, environmental quality, etc. Accordingly, the Department iden- tifies and subsequently manages projects which yield "high returns." To illustrate, one study indicated that actual drilling times of deeper gas wells amounted to 45 percent of all time on the wells? Another source indicated that time spent turning-to- the-right comprises 41 percent of the rig up-to-rig down time needed to drill gas wells! These data clearly indicate that improving drilling performance is one strategy warranting implementation.

Natural gas RD&D at DOE/Morgantown is fully coordinated with that of the Gas Research Institute (GRI). Benefits of the complementary projects are mutual and include: coordination of future plans and strategies, leveraging of available funds, overall improved communication, barrier/ issue identification, and benefit identification and quantification.

To maximize results, DCS projects are also fully coordinated with the activities of other Federal elements, e.g., the Geothermal Division within the Office of Energy Efficiency and Renewable Energy. In this case, common issues revolve around reducing the

2 DOE I FOSSIL ENERGY'S DRILLING, COMPLETION. AND STIMUlATiON RD&D A TECHNOLOGIES /PRODUCTS OVERVIEW

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capital costs required to construct wells in hard, abrasive rock and at higher temperatures. Another area of coordination relates to the National Advanced Drilling and Excavation Technologies program (NADET)? Managers at DOElMorgantown remain cognizant of NADET activities and participate in individual proj- ects, as warranted.

The RD&D is structured to include an appropriate balance of near-, mid-. and long-term efforts. Development of the high- power, slimhole drilling system is an example of a near-term project. In that project, technology transfer is ongoing and deployment of the drilling system is expected soon after field testing is complete. This method of rapid deployment is based, in part, on significant performance of the drilling system in the laboratory. The high-pressure, downhole pump @HPTM) is expected to be a commercial service in the mid-term. For the long-term, revolutionary drilling systems are being investigated with the current advanced drilling systems study designed to identify systems with significant potential.

RD&D within the DCS product line is industry-driven and as such, the products are readily deployed by industry. Industry is therefore, the recipient of cost savings and performance improve- ments in as short a time as possible. Commercialization of DCS products is also facilitated via the alliances developed with the industry's service sector. As dictated by the maturity of a technology, cost-shared service company partnerships are negoti- ated. Teaming with the service sector also allows industry to realize benefits sooner and at lower costs via the well-developed infrastructure.

As reported, one focus of the DCS product area is drilling performance, i.e., to increase rate-of-penetration (ROP). Specific projects include: - High-pressure DHPm for jet-assist drilling,

High power, slimhole drilling system, Air percussion bottom hole assembly (BHA), and - Underbalanced drilling, in general.

In the underbalanced drilling area, several "tools" are being developed and tested to expand deployment of the technology. These include a state-of-the-art (SOA) foam-drilling fluid model, testing of lightweight solid additives for conventional muds, and two elemmagnetic-based systems for the telemetry of LWDl MWD data. Other technologies being addressed in DOE'S pro- gram include slimhole, directional / horizontal drilling, and minimum formation damage stimulation fluids. Many of the products being developed and tested crosscut technology areas, e.g., the high-power, slimhole drilling system. From the afore- mentioned. it should be abundantly clear that a portfolio of products/technologies are being investigated in order to affect a variety of geologic settings, well depths, etc.

Background The number of successful natural gas wells in the Lower-48 will have to more than double in 2010, in order to meet the forecasted supply at that time. The Energy Information Adminis- tration reports that more than 7,200 natural gas wells were

completed in 1994, and that more than 16,000 will be needed in 2010 to meet the Luwer-48 primary production requirement of 20.4 Tcf." Overall, more than 20,000 total wells (oil, gas. and dry) were drilled during 1993 with a projection of 57,000 total wells for 2010. Current and anticipated drilling activity, therefore, provides a significant impetus for conducting natural gas drilling RD&D.

Domestic drilling costs totaled more than $10 billion in 1993." Use of simple arithmetic results in total domestic drilling costs approaching $30 biilion in the year 2010. At this expenditure level, just a 1 to 2 percent overall cost reduction would yield a several hundred million dollar savings to industry - truly a worthy goal. Hydraulic-fracturing costs approached $1 billion (1994)." Again, jusr a few percent cost reduction can yield a savings of tens of millions of dollars. Also noteworthy, the GRI drilling team has independently estimated the potential cost savings for well construction on the order of a few hundred mil- lion dollars for the year 2OOO.I3

The previous sections have provided a framework for the DCS activities, including the organizational aspects, strategies being employed, and potential benefits to industry. With that back- ground, summaries of the key projects are provided in the fol- lowing section.

Project Summaries Steerable Air-Percussion BHA. A steerable percussion air- drilling system is being developed for use in hard rock settings. The hammer is being developed to:

Yield a percussion drilling assembly that is independent of drill string rotation,

Include auxiliary bottomhole components, e.g., bent subs, stabilizers, etc., and

Investigatelintegrate use of the percussion assembly with telemetry systems which are not dependent on mud as a trans- mission medium.

Conventional percussion air-drilling methods yield very high ROP but are limited to straight holes. Fig. 2 shows ROP's for three rock types. The system under development will combine the high ROP aspects of a percussion device with the directional control features typical of downhole motors. Equipment design, fabrication, and field testing comprise the effort. Initially, the system's ability to drill straight holes independent of rotation will be demonstrated, followed by assessment of its ability to turn. build, or drop angle. Build rates as a function of bent sub angle in directional wells and the maintenance of inclination during horizontal drilling will also be studied during the project. The steerable hammer is schematically shown in Fig. 3.

Five field tests were conducted during 1994 in west Texas and in West Virginia. High ROPs were achieved in all tests; how- ever, a torque-related piston stalling problem surfaced. The stalling seems to be a function of the extreme rotational resis- tance torque which the bit has to overcome when excessive weight-on-bit (WOB) is applied. At present, hammer and bit re- designs are being implemented with additional field tests planned.

SPE 30993 JOHN R. DUDA. ALBERT B. YOST I I 3

Neat-Bit Sensors. Horizontal and directional well lengths have become increasingly longer and the need for accurate placement of the boreholes has become more critical. Accordingly, mea- surements of directional data and formation parameters at the drill bit are required in order efficiently drill within a small window in the target horizon. A near-bit sensor telemetry sub has been designed and fabricated to acquire and transmit data from just behind the bit to a base MWD system.

Phase I of the project prepared performance specifications of the unit. followed by design, fabrication. and testing of a proto- type toot. In Phase LI of the project, the form, fit, and overall improved communication functionality of the sensor sub will be tested in the field. The sub is 6-3/4 inch OD and communicates via electromagnetic (EM) telemetry. The system is designed to work with mud motors and stabilized BHA from all manufac- turers. and passes data messages to third party steering tools or conventional MWD systems. Fig. 4 shows the sensor subconcept, and additional data are listed in Table 1.

The combination of inclination and formation data obtained at the bit enables well placements to be optimized in terms of lower installation costs, reduced lifetime maintenance, and maximized productivity. Use of the sensor sub should signifi- cantly preempt the need for well path corrections thus avoiding costly p!ug back and re-drill operations. The tool is being vibration tested, and plans are to evaluate the tool in two drilling wells. Any final tool modifications will then be made to ready the sensor sub for use as a commercial service.

High-Power Slimhole DrilIing System. A slimhole, multi-lobe downhole drilling motor has been designed and fabricated to take advantage of the cutting potential of thermally stable polycry- stalline diamond (TSD) bits. In prior tests,I4 drilling with motors and TSD’s in an overpowered mode, the full cutting potential of the bits wasn’t realized. Hence, the genesis of this project.

The 3-3/8 in OD motor has the following improved features: Increased rotor - stator interference, Higher strength universal, Longer power section, and Higher performance bearing pack.

The high-power motor is a 415 design and is expected to deliver 34 hp and 750 ft-lbs, of torque at 70 gpm [235 rpm]. The motor will be operated with about a 150 psi pressure drop per stage. Fig. 5 illustrates the upgraded features of the motor.

At present, all components have been assembled and motor performance is being evaluated through dynamometer testing, Initial performance results (dynamometer) are depicted in Fig. 6. Once performance is assured, drilling tests of the system (motor/TSD) will be completed in a controlled environment. Final efforts will be field tests of the system to verify performance in the actual drilling of wells. Commercial availability of the drilling system is anticipated for 1996.

Advanced Drilling Systems Study. Interest in advanced drilling systems is high and is based on the financial aspects of drilling. As stated in the introduction section, drilling costs are

approximately $10 billion domestically and $75 billion, worldwide.” Obviously, the incentive to develop reduced-cost methods of drilling are great.

A prior study of advanced drilling systems reviewed previous work, much of which was completed in the 1960’s and 7O’s.l6 The present effort, however, couples the review with a charac- terization of viable advanced drilling systems and the current SOA technology that applies to those systems.

Initially, various drilling systems were identified and charac- terized. The basic rock destruction concepts and other functional descriptions have been completed. Current technology, emerging technology. and hypothetical concepts have been described. Required equipment and information concerning capital/operating costs have been collected and are being analyzed. A fairly extensive survey of industry was included in the study. Current efforts in drilling research span a range of nearly commercial systems to highly speculative concepts.

Findings of the study will be. disseminated via a final report, expected to be available during the late fall of 1995.

Russian Drilling Study. The subject effort is designed to review and analyze research carried out in the former USSR during the past 30 years, with emphasis placed on work per- formed since the 1970’s. Through time, thousands of scientists and engineers have conducted drilling systems R&D in the former USSR working at scores of institutes and bureaus. The Department’s goal is to assimilate former USSR technology advances into current SOA and developing products / tech- nologies. By doing so, evolutionary and novel drilling techniques and tools can be commercialized sooner, thus benefitting the industry at the earliest time.

The study classifies drilling technology /systems based on the type of energy used for rock destruction as follows:

Explosive and chemical, Novel mechanical drills, High-pressure jet drills, Thermal drills, Electrothermal drills, and Combined novel drills.

Emphasis is placed on applied work efforts, as opposed to theoretical, irrespective of the degree of completion: laboratory- and field-tested techniques; and combined novel and conventional methods which maximize energy delivered to the rock. The competitiveness of various systems is examined considering envi- ronmental, technical, economic, and power consumption aspects. Shallow and deep well considerations are studied. Results of the drilling study are expected to be available late in 1995.

EM-Based MWD System. Drilling in an underbalanced mode provides two significant advantages compared to conventional mud drilling at balanced or slightly overbalanced conditions: (1) increased ROP and (2) reduced formation damage. In order to promote a broader use of underbalanced drilling. tools must be available to fully facilitate well construction. Hence, this project to design, fabricate, and test a slimhole, EM-based MWD system.

4 DOE / FOSSIL ENERGY’S DRILLING, COMPLETION, AND STIMULATION RD&D A TECHNOLOGIES/PRODUCTS OVERVIEW

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More specifically, a wireless MWD system is being developed that will operate reliably in air, air-mist, air-foam, and other underbalanced environments during drilling operations using motors and/or other BHA’s. This technology is particu- larly applicable to low-pressure, water-sensitive, and low- permeability formations when drilling is directional or horizontal.

The system under development will: Be suitable for use in slimholes, Le., capable of use in

6-1 /4 in wells via small diameter downhole instrumentation unit, Facilitate higher data rates to greater depths through use of

a drill string repeater, Consist of a fully retrievable repeater unit, Reliably operate in all formation types, drilling fluids, and

wellbore orientations, and Be compatible with other steering, data acquisition equip-

ment to orient and steer, and measure formation properties and drilling parameters.

Multiple field tests are planned to fully test the reliability of the enhanced system. These tests are scheduled to begin in the late fall of 1995. Field test results will be reported in a timely manner. The telemetry system is illustrated in Fig. 7.

Underbalanced Drilling Products. In order to broaden the use of underbalanced drilling technology, easy-to-use “tools” must be available to operators and service companies. Two products are being developed and tested in this project. These are: (1) a PC- based, SOA foam-drilling fluid model for rig site use and (2) lightweight solid additives for use in conventional mud systems.

The PC foam-drilling fluid model is based, in part, on a mainframe code developed by a major operator.” As required, recent mathematical advances have been incorporated into the code and the model formatted for Windowsm. The model takes into account the effects of pressure, temperature, and electro- chemical changes on the foam quality, thus allowing accurate prediction of pressures and selection of rig equipment. Fig. 8 illustrates two of the screens available when utilizing the model.

Lightweight solid additives (LWSA, lightweight hollow spheres) are being tested as to their usefulness in reducing mud weights. The LWSA have a specific gravity of about 0.4 and crush-resistive strengths of several thousand psi. Prior uses of lightweight additives have been in cement slumes to reduce their density. In muds, use of the LWSA is expected to increase ROP and reduce formation damage. A representation of drilling mud with the LWSA is shown in Fig. 9.

Development of the foam model is complete and validation of the model outputs are being verified using laboratory data. Once the results are validated, the model will be field tested during actual foam-drilling operations. A battery of laboratory tests are being conducted on the LWSA muds, with emphasis on rheological properties and the ability to process the additive-laden mud at the outflow. Additive durability and economic considerations are also being investigated. Field- drilling tests using the LWSA are also planned.

The model will be made available to operators, contractors, and service companies in order to effect increased use of

underbalanced drilling practices. As warranted, the LWSA addi- tives will also be made available as a commercial product for drilling applications.

High-pressure Downhole Pump for Jet-Assist Drilling. Through a closely coordinated effort, the DOE/Morgantown and GRI are developing and testing a high-pressure downhole pump for jet-assist drilling. The downhole intensifier is intended for use in deeper and harder rock drilling and in other time-sensitive cost situations. The pump is expected to deliver ROP increases of 1.5 to 2 times that of conventional drilling.

The downhole pump is designed to produce 30.000 psi using part of the mud stream. The ultra-high pressure mud is then directed to the bottom of the hole via a modified rock bit. The high pressure is generated using the piston (reciprocating) princi- ple and a clever valving setup. Fig. 10 illustrates the conceptual design of the pump. The DHPm is &3/4 inch in diameter, designed for use in 7-718-inch wellbores.

At the present time, pump design is rapidly advancing from the experimental stage to that of a commercial prototype. Pump redesign has eliminated more than 30 seals and improved pump efficiency. Pump components have been extensively tested in the laboratory, and two field tests have been completed with the experimental unit. Field test results indicate ROP increases of 1.5 to 2 times that of conventional methods. Fig. 11 shows a comparison of jet-assist and conventional drilling performance. Long-lead components have been ordered for the commercial prototype and the laboratory testing of the unit is scheduled to begin in the fall of 1995. Numerous field tests of the prototype unit are planned in order to harden the design and acquire a critical amount of data to support the start-up of a commercial service.

.

Fracturing Fluid Characterization Facility. The fracturing fluid characterization facility (FFCF) is a sophisticated physical test cell for studying the hydraulic-fracturing process. The facility is located at Oklahoma University and is co-sponsored by the DOE and GRI. Other partners include Halliburton Energy Services and MTS Systems Corporation.

The facility consists of a large, high-pressure steel test cell, essentially being a parallel plate model. The cell measures 10 feet x 10 feet x 10 feet and weighs slightly over 35 tons. The interior is fitted with movable plates with rock facings to simu- late the faces of an induced crack. Resistive forces to fracture initiation and growth can be modeled by manipulating the cell’s plates. Pressure rating of the cell is 1200 psi with a temperature limit of 250°F. The cell is illustrated in Fig. 12.

During experimentation, SOA instrumentation monitors the shape of the fracture as it propagates. The properties of frac- turing fluids and of proppant-laden slurries are also measured to determine changes during the process and their responses to dif- ferent pressures, temperatures, and rates. Presently, rheological investigations are underway involving linear and cross-linked gels, as are proppant transport studies.

SPE 30993 JOHN R. DUDA, ALBERT 8. YOST II 5

Field Fracture Multi-Site Facility. The Department, in coordi- nation with the GRI. has in-place a project designed to give the natural gas industry much greater precision in designing frac- turing treatments. The M-sites project uses seismic measure- ments and computerized data processing systems to analyze the geometry of fractures pumped in low-permeability formations.

The project is field based with the multi-well experiment site hosting the fracturing/diagnostic effort. At that site, multiple, closely spaced wells were previously drilled, including a direc- tional borehole. Fig. 13 shows the well site with proposed wells. Because the multi-well experiment site is so well characterized from prior studies, and the present wells allow reservoir access, considerable capital was reserved for diagnostics rather than accessing the reservoir. Seismic surveys, along with pressure- time measurements, are being used to map the lengths and directions of hydraulically induced fractures. Natural gas flow rates are monitored to assess the effectiveness of the stimulation and other well management techniques.

At present, diagnostic wells are being drilled in preparation for fracturing experiments. The project is a major step toward improving the predictability of hydraulic fracturing. The project is likely to lead to technology that will enhance fracturing efficiency and increase the Nation's recovery of natural gas from its massive deposits of western tight sandstones. The efficiency improvements will also save operators significant capital since hydraulic fracturing is a billion-dollar service business in the petroleum industry.

CO,/Sand-Fracturing Technology. The DOE is testing and introducing a minimum formation damaging fracturing process designed to effect widespread deployment of the technology. The stimulation process consists of liquid carbon dioxide (CO,) as the carrier fluid and sand as the proppant. This technology has the potential to increase early-time gas production rates by 200 to 500 percent. In addition, workover/swab rig costs can be avoided since no liquids require removal from the well during cleanup.

The stimulation treatments utilize liquid CO, and sand slurried in a unique closed-system blender. The slurry is pumped at turbulent flow rates. After placing the proppant, the CO, vaporizes leaving a liquid-free propped fracture. The process does not use gel additives, hence residue and accompanying plugging are precluded. References 18 and 19 provide a more detailed description of the fracturing process and production responses. Conceptually, the wellsite setup is shown in Fig. 14. Early test results are shown in Table 2, along with cumulative gas production as a result of foam and nitrogen gas fracs.

The CO,/sand-fracturing process is commonly pumped in western Canada but attempts at commercialization in the Lower48 have only recently surfaced. Approximately 20 field tests have been pumped in the Appalachian basin, with 15 additional tests planned. Complete assessment of the technology also calls for testing the process throughout the natural gas-producing basins in the western United States, in a variety of geologic formations. The technology is especially applicable in low-pressure and water-sensitive formations which are slow to cleanup.

Wrap-up Discussion An overview of natural gas drilling, completion, and stimulation RD&D sponsored by the US. DOE has been presented, serving as a technology transfer medium. Organizational aspects sup- porting the RD&D have been disclosed and summaries of major projects detailed. The DOE program is closely coordinated with GRI and focused to yield high "payback," primarily in the drilling performance technologies area PIans are to continue the development of an RD&D portfolio and accelerate the deploy- ment of the technologies/prduct.

Nomenclature BHA = bottom hole assembly

C = centigrade CO, = carbon dioxide

DCS = drilling, completion, and stimulation DHP" = downhole pump

DOE = Department of Energy EM = electromagnetic

FE = Fossil Energy F = Fahrenheit

FFCF = Fracturing Fluid Characterization Facility ji = feet

gpm = gallons per minute GRI = Gas Research Institute

hp = horsepower in = inch 16, = pounds (force)

drilling LWD/MWD = logging-while-drilling /measurement-while-

LWSA = lightweight solid additives M.D. = measured depth

MMcf = million standard cubic feet per day MWX = multi-we11 experiment N2 = nitrogen

NADET = National Advanced Drilling & Excavation Technologies

OD = outside diameter PC = personal computer ppg = pound,,, per gallon psi = Ibf per square inch

ROP = rate-of-penetration rpm = revolutions per minute S.G. = specific gravity SOA = state-of-the-art

TSD = thermally stable polycrystalline diamond U.S. = United States

UHP = ultra-high pressure WOB = weight-on-bit

WV = West Virginia

RD&D = research, development, and demonstration

Tcf = trillion standard cubic feet

O =degree

References 1. U.S. Department of Energy: 1994. "Fueling a Competitive

Economy." Strategic Plan (April) DOE/S-0108.

6 DOE /FOSSIL ENERGY'S DRILLING, COMPLETION, AND STIMULATION RD&D: A TECHNOLOGIESIPRODUCTS OVERVIEW

SPE 30993

2. U.S. Department of Energy: 1993. "Natural Gas Strategic Plan and Multi-Year Program Crosscut Plan FY1994-1999" (December), DOE/FE-O297P.

3. U.S. Department of Energy: 1993. "The Domestic Natural Gas and Oil Initiative" (December).

4. U.S. Department of Energy: 1994. Natural Gas Strategic Plan, Supply Technical Panel Strategic Plan, FY1995-2OOO Planning Manual (October).

5. U.S. Department of Energy /Morgantown: 1994. "METC Strategic Plan 1994" (August).

6. Layne, A.W., and A.B. Yost 11: 1994. "Development of Advanced Drilling, Completion, and Stimulation Systems for Minimum Formation Damage and Improved Efficiency: A Program Overview," SPE/DOE 27353, Presented in Lafayette (February).

7. U.S. Department of Energy/METC: 1995. "Natural Gas RD&D Contractors Review Meeting," Agenda, Abstracts, and Visuals, Section 7.4 (April).

8. Aslakson, John: 1995. Drilling Technology Team Notes from Natural Gas Supply Project Advisors Meeting (May).

9. Mock, J.E., A.J. Jelacic, and P.M. Dorr: 1994. "The National Advanced Drilling and Excavation Technologies (NADET) Program: A New Collaborative Research and Development Initiative," IADC/SPE 27505, Presented in Dallas (February).

10. Energy Information Administration: 1995. "Annual Energy Outlook 1995 with Projections to 2010 (January), DOE/ EIA-0383(95).

11. Energy Information Administration: 1995. "Annual Energy Review 1994" (July), DOE/ ElA-0384(94).

12. Gas Research Institute: 1995. "Gas Research Institute Digest." Summer Issue.

13. Aslakson. John: 1995. Drilling Technology Team Notes from Natural Gas Supply Project Advisors Meeting (May).

14. Cohen, J.H.: 1994. "Development of High Power TSP Bits & Downhole Drilling Motors," Presented at the Gas Research Institute's Technical Advisory Group Meeting held in Houston (July).

15. Pierce, K.G., and Livesay. BJ.: 1995. "Advanced Drilling Systems Study," DRAFT (July).

16. Maurer, William C.: 1980. "Advanced Drilling Tech- niques." Petroleum Publishing Co., Tulsa, OK 74101

17. Maurer, W.C., and Medley, Jr., G.H.: 1995. "Development and Testing of Underbalanced Drilling Products," currently being published in proceedings of the U.S. DOE Natural Gas Contractors Review Meeting held in Baton Rouge (April).

18. Yost, A.B., II, R.L. Mazza, and J.B. G e k 1993. TO,/ Sand Fracturing in Devonian Shales," SPE/DOE 26925. Presented in Pittsburgh (November).

19. Yost, A.B.. 11. R.L. Maua. and R.E. Remington 11: 1994. "Analysis of Production Responses to C02/ Sand Fracturing: A Case Study," SPE 29191. Presented in Charleston (November).

(698 pgs).

6 3/4" OD Near-Bit MWD System (Mechanical)

Sub Diameter 6.750 Inches Sub Length 34 Inches Assembled

Flow Area 7.85 Square Inches Over Pull Capacity Pressure Rating 15,000 psi Material Construction 4140 Tool Joints

> 200,000 LBF

4 1/2 API Reg Pin x 4 1/2 M I Reg Box (Down)

(Sensory)

Type of Sensor Data:

Range Inclination 0.1 Degrees Accuracy

Temperature 125 Degrees C Pressure 15,000 psi

~~~~

Table 1. Near-Bit Sensor Sub-Assembly Specifications

SPE 30993 JOHN R. DUDA. ALBERT B. YOST II 7

Gas Production Comparisons - 19 Months Pike Co., KY

Combined Average Group (MMcf per Well)

C02/Sand

N2 Gas

N2 Foam .

48.3

23.5

11.3

Incremental. Gas Benefit Ratio (MMc9

CO$Sand : N2 Gas 2.1

COZ/Sand : N2 Foam 4.3

24.8

37.0

Table 2. Early-Time Production Results: C0,ISand Fracs

Structure of Program Implementation - 'Quicklook' - us.1 Dept of Energy

I I DomesUc Natural Gas & Oil Initiative

office of Fossil Energy

I Natural Gas Suppry Technology Panel

Fuels Resources Supply 'Business Unlt'

I Drilling. Completion. & Stimulation

Pmdudune

I

Figure 1. Hierarchy of Natural Gas RD&D Implementation

300 1 250 - =: 200 9 Granite

- 150

2 100 5 Sandstone

w b

n

5 0

0 200 300 3sp t ine Pressure (psig)

Figure 2. Air Percussion BHA Performance Three Rock Types

8 " DOEIFOSSIL ENERGY'S DRILLING. COMPLETION. AND STIMULATION RD1D: A TECHNOLOGIES /PRODUCTS OVERVIEW

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Rotating Oirectional Hammer Bottomhole Assembly

Figure 3. Schematic of Steerable Hammer Figure 4. Near-Bit Sensor Sub-Assembly Concept

Figure 5. Schematic of High-Power Drilling System Figure 6. Performance of High-Power Slimhole Motor

Model-29 Electromagnetic (EM) Measurement - While - Drilling (MWD) System for

Underbalanced Directional Drilling 1 = Non-Mag Collar 2 =Antenna Sub Drillers

m!..-.-.. uispiay

Downhole Terminal Unit

Figure 7. EM-Based Telemetry System

Pressure Profile I

7 - -

i Foam Quality vs MD. I

nouow SPHERES UGHT WE'GHT MUD MUD

+ 0 0 0

O 0 0 00° 0 0

1.02 S.G. 0.38 S.G. 0.70 S.G. 8.5 PP9 3.17 PPS 5-04 PP9

Figure 8. Foam-Drilling Fluid Model Screen Displays Figure 9. Representation of Drilling Mud With LWSA

DOEIFOSSIL ENERGY'S DRILLING, COMPLETION. AND STIMULATION RDBD: A TECHNOLOGIESIPRODUCTS OVERVIEW

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UHP Outlet Drive fluid Drive fluld Exhaust Chedc Valve UHP fluld (35 ks9

\ / I

I I Charge Presswe / UHP Seal

1 , 7000

Figure 10. Conceptual Design of the High-pressure Downhole Pump

Multlple Drive Pistons 1

Jet-Assist Drilling (East Texas Well)

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Figure 11. Performance of Jet-Assist and Conventional Drilling

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Figure 12. The Fracture Fluid Characterization FaciIity

SPE 30993 JOHN R. DUDA, ALBERT B. YOST il 11

Pian View of Test Wells Seismic Signal Receiving Well

JDUDA\1:951505

Seismic Signals From Propagating Fracture MWX-3 7

Treatment We

0 100 200 I 1 1

KEY: 0 NewWeU

e Existingwell Scale. Feet M93001578W

Figure 13. Schematic of the M-Site Project

Flow Una I I I

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Figure 14. Logistics of COJSand-Fracturing Treatment