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Improving Gas Well Drilling and Completion with High Energy Lasers
Brian C. Gahan
Gas Technology Institute
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Drilling for Oil and Gas in the US
Oil and Gas Wells Drilled, 1985-2000Exploratory and Development
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Total Footage Drilled (Oil, Gas, &Dry Holes)
Petroleum Total Wells Completed
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1959 1964 1969 1974 1979 1984 1989 1994
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Dep
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Average Cost per Foot
Average Depth per Well
Drilling for Oil and Gas in the US
Estimated Cost Per Foot and Average Depth Per Well of All Wells (Oil, Gas and Dry) Drilled Onshore in the U.S. from 1959 - 1999 (DeGolyer and MacNaughton, 2000)
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Drilling for Oil and Gas in the US
1990 GRI Study on Drilling Costs
Major Categories % of Total Time
Making Hole 48
Changing Bits 27
And Steel Casing
Well & Formation Characteristics 25
Total Drilling Time 100% .
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High-energy Laser Applications
Lasers could play a significant role
as a vertical boring &
perforating tool in gas well drilling
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System Vision
Laser on surface or within drilling tubing applies infrared energy to the working face of the borehole.
The downhole assembly includes sensors that measure standard geophysical formation information, as well as imaging of the borehole wall, all in real time.
Excavated material is circulated to the surface as solid particles
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System Vision
When desired, some or all of the excavated material is melted and forced into and against the wall rock.
The ceramic thus formed can replace the steel casing currently used to line well bores to stabilize the well and to control abnormal pressures.
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System Vision
When the well bore reaches its target depth, the well is completed by using the same laser emergy to perforate through the ceramic casing.
All this is done in one pass without removing the drill string from the hole.
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Laser Product Development
LASER BASIC RESEARCH
Laser FE
Laser DrillingAssist
Laser Perf
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Off Ramp: Perforating Tool
Proposal Submitted to Service Industry Partner
Purpose– Complete or re-complete
existing well using laser energy
Requirements– Durable, reliable laser
system– Energy delivery system– Purpose designed
downhole assembly
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Preliminary Feasibility Study
Laser Drilling Experiments – 11/97– Basic Research – 2 years
Three High-Powered Military Lasers– Chemical Oxygen Iodine Laser (COIL)– Mid Infra-Red Advanced Chemical
Laser (MIRACL) – CO2 Laser
Various Rock Types Studied– Sandstone, Limestone, Shale– Granite, Concrete, Salt
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MIRACL – Simulated Perf Shot
A two-inch laser beam is sent to the side of a sandstone sample to simulate a horizontal drilling application.
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MIRACL – Simulated Borehole Shot
After a four-second exposure to the beam, a hole is blasted through the sandstone sample, removing six pounds of material.
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GRI-Funded Study Conclusions
Previous Literature Overestimated SE Existing Lasers Able to Penetrate All Rock Laser/Rock Interactions Are a Function of
Rock and Laser (Spall, Melt or Vaporize) Secondary Effects Reduce Destruction Melt Sheaths Similar to Ceramic
Study Conclusions Indicate Additional Research is Warranted
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Laser Drilling Team – Phase IGas Technology Institute
DOE NETL
Argonne National Laboratory
Colorado School of Mines
Parker Geoscience Consulting
Halliburton Energy Services
PDVSA-Intevep, S.A
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Drilling With The Power Of Light DOE Cooperative Agreement DE-FC26-00NT40917
– Original Proposed Tasks and Timeline
Quarter 3 4 1 2 3 4 1 2 3 4 1 2
Quarter 1 2 3 4 1 2 3 4 1 2 3 4Task 1. Project Structure and ManagementTask 2. Fundamental Research2.1 Laser cutting energy
assessment series2.2 Variable Pulse Laser Effects2.3 Drilling Under Insitu
Conditions2.4 Rock-Melt Lining Stability2.5 Gas Storage Stimulation2.6 Laser Induced Rock
Fracturing Model2.7 Laser Drilling Engineering
Issue IdentificationTask 3. System Design Integration3.1 Solids Control3.2 Pressure Control3.3 Bottom-hole Assembly3.4 High Energy Transmission3.5 Completion and Stimulation
Techniques for Gas Well Drilling
3.6 Completion and Stimulation Techniques for Gas Storage Wells
Task 4. Data Synthesis and InterpretationTask 5. Integration and ReportingTask 6. MilestonesTask 7.Technology Transfer
Year 3Year 2Year 1
TABLE 3: WORK TASK TIMELINES2001 2002 20032000
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First Phase (FY-01) Objectives
Accepted Phase 1 Task List1. Laser cutting energy assessment
2. Variable pulse laser effects (Nd:YAG)
3. Lasing through liquids
Quarter 4 1 2 3
Quarter 1 2 3 41.0 Project Structure and
Management
1.1 Laser cutting energy assessment series
1.2 Variable Pulse Laser Effects
1.3 Conduct Lasing Through Liquids
1.4 Topical Report
Year 1
20012000TABLE 3: WORK TASK TIMELINES
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Phase I Laser: 1.6 kW Nd:YAG
Focusing Optics
Laser Beam
Rock
7.6 cm
Neodymium Yttrium Aluminum Garnet (Nd:YAG)
1.27 cm
Coaxial Gas Purge
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Conclusions: GTI/DOE Phase I
SE for Shale 10x Less Than SS or LS Pulsed Lasers Cut Faster & With Less
Energy Than Continuous Wave Lasers. Fluid Saturated Rocks Cut Faster Than Dry
Rocks. Possible Mechanisms Include:
More Rapid Heat Transfer Away From the Cutting Face Suppressing Melting
Steam Expansion of Water Contributing to Spallation
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Conclusions: GTI/DOE Phase I
Optimal Laser Parameters Observed to Minimize SE for Each Rock Type
Shorter Total Duration Pulses Reduce Secondary Effects from Heat Accumulation
Rethink Laser Application Theory – Rate of Application: Blasting vs Chipping
Unlimited Downhole Applications Possible due to Precision and Control (i.e., direction, power, etc.)
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DOE-GTI/NGOTP-ANL Phase 2 In Progress
Continuation of SE Investigations– Effects at In-Situ Conditions – Effects of Multiple Bursts and
Relaxation Time– Observations at Melt/Vapor Boundary
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Supporting Slides Detailing Phase I Work
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Laser Cutting Energy Assessment
Measure specific energy (SE) – Limitation of variables
• SS, shale and LS samples• Minimize secondary effects
– Identify laser-rock interaction mechanisms (zones)• Spall, melt, vaporize
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Just Enough Power
Conducted Linear Tests– Constant Velocity Beam Application (dx)– Constant Velocity Focal Change (dz)
Five Zones Defined in Linear Tests Identified Zones Judged Desirable for
Rapid Material Removal– Boundary Parameters Determined for Spall into
Melt Conditions
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Laser/Rock Interaction Zones
Zone Called Thermal Spallation Judged Desirable for Rapid Material Removal
Optimal Laser Parameters Were Determined to Minimize:– Melting – Specific Energy (SE) Values– Other Energy Absorbing Secondary Effects, and– Maximize Rock Removal
Short Beam Pulses Provided “Chipping” Mechanism Comparable to Conventional Mechanical Methods
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Zonal Differences
SE differs greatly between zones Shale shows clear SE change between
melt/no melt zones Much analysis remains to understand
sensitivities of different variables
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SE vs Measured Average Power (kW)
SH11A
SH10
SH11B2
SH18A
SH12B2
SH8
SH11B1
SH13A
SH15A1
SH15A2SH12B1 SH2 SH6
R2 = 0.9095
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Measured Average Power (kW)
Sp
ecif
ic E
ner
gy
(kJ/
cc)
Zone 3 - Significant Melt
Zone 2 - No MeltMinimum SE
Spallation
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Lithology Differences
Differences between lithologies more pronounced when secondary effects minimized
Shale has lowest SE by an order of magnitude.
Sandstone and limestone remain similar, as in CW tests
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All ND:YAG Tests
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Average Power W
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Sandstone Limestone Shale
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SE Values: Wet vs. Dry Samples
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Power (kW)
Spe
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nerg
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Dry rock samples Dry rock samples Water-saturated samples
Dry
Wet
Atmospheric Conditions.