southwestern petroleum short course lubbock, texas april 18 – 19, 2012 tulsa university horizontal...

Southwestern Petroleum Short Course

Lubbock, Texas

April 18 – 19, 2012

Tulsa University Horizontal Well Artificial Lift Projects (TUHWALP)

Cleon Dunham, ALRDCBill Lane, WeatherfordGuillermo Leal, BPJames Martin, ConsultantCem Sarica, Univ. of TulsaRob Sutton, Marathon Oil

April 18 - 19, 2012 2012 Southwestern Petroleum Short Course 2


• Introduction

– Vast majority of new wells for both oil and gas are horizontals.

– Most require artificial lift to produce liquids and/or dewater gas wells.

– Artificial lift of horizontal wells is challenging.

– It is particularly challenging in shale assets where wells are often deep with long horizontal sections.

Complex Horizontal Well Profiles10,100

10,150

10,200

10,250

10,300

10,350

0 1,000 2,000 3,000 4,000 5,000 6,000 7,000

Departure, ft

Tru

e V

ert

ica

l De

pth

, ft

Well 1

Well 2

Well 3

Well 4

Well 5

Well 6

Well 7

Well 8

Well 9

Well 10



• Introduction (continued)

– To address these challenges, the ALRDC invited many companies to form a Consortium.

– The purpose is to develop new methods and understanding for advancing artificial lift.

– Several organizations were evaluated to lead the Consortium.

– The University of Tulsa was chosen.

• Track record with leading consortia.

• Extensive R&D facilities.

Horizontal Well Scope in the World• Scope

– Face of industry has changed dramatically in last few years.

– Largest change is associated with the producing natural gas, condensates, and oil from shale formations.


Horizontal Well Scope in the USand the Eagle Ford in Texas


• Scope in the US

Rate of Development in Recent Years• Rate of Adding New Wells and Production

– Drilling rate in Marcellus Shale in Appalachian Basin

– Drilling rate in Barnett Shale in Texas

– Gas production increase in Barnett Shale


Why Horizontal Wells• Reason for Horizontal Wells

– Producing gas and oil from shale formations requires drilling, completing, and operating horizontal wells.

– Horizontal wells are needed to contact large portions of reservoirs and natural “micro” fractures they contain.

– Wells must be treated with multi-stage hydraulic fractures to permit oil and gas to flow from reservoirs to wellbores.


Horizontal Well Challenges


• Challenges in producing horizontal wells

– Much of water used to fracture wells must be produced back to reduce back-pressure and clear flow paths for gas and oil production.

– Often some fracture sand will be produced back with the water; both water and sand must be artificially lifted from the wells.

– Most artificial lift systems are designed to work in vertical sections of wells.

– Methods must be developed to help sweep and lift fluids from the deviated and/or horizontal portions of the wellbores.

– Most “horizontal” wells are not actually horizontal.

Typical Horizontal Well Profiles• Typical “Horizontal Wells” Aren’t Really Horizontal

– Here are some typical profiles.


Complex Horizontal Well Profiles10,100

10,150

10,200

10,250

10,300

10,350

0 1,000 2,000 3,000 4,000 5,000 6,000 7,000

Departure, ft

Tru

e V

ert

ica

l De

pth

, ft

Well 1

Well 2

Well 3

Well 4

Well 5

Well 6

Well 7

Well 8

Well 9

Well 10

Typical Horizontal Well Profiles• And the Story Becomes More Complicated

– Often “horizontal” portions of the wells have up and down undulations.

– Water can accumulate in low spots and be produced to “vertical” part of the well in slugs.

– This can make artificial lift challenging, especially with pumping systems.


Understanding Critical Flow• Basis for a Horizontal Well Artificial Lift Consortium

– Reasonable methods exist to determine “critical” gas flow velocities needed to lift liquid from vertical gas wells.

– We need improved understanding and models to determine “critical” gas flow velocities in horizontal wells.

– And we need to know more about how to artificially lift these wells.

– For these and other reasons, the Petroleum Industry is forming a Horizontal Well Artificial Lift Consortium.


Horizontal Well Consortium Mission Statement

• Mission Statement

– Work cooperatively in the Petroleum Industry to:

• Develop recommended practices for artificially lifting horizontal wells.

• Make recommendations for design and operability of horizontal wells with regard to artificial lift.

• Improve selection, deployment, operation, maintenance, monitoring, and control of production and artificial lift solutions, equipment, and practices to optimize recovery of natural gas and associated liquids from horizontal oil and gas wells.

– Advance the knowledge and effectiveness of people who design and operate horizontal wells.


Primary Focus of Consortium

• Primary Focus of the Consortium

– Initially, the primary focus was on horizontal gas wells.

– However, with shifting economics of oil and gas production,

– And with increases in liquid production from horizontal shale formations,

– The emphasis has expanded to focus on both liquid and gas production.


Survey of Operatingand Service Companies

• Survey

– The next step was to survey interested companies to discern their challenges and priorities for dealing with horizontal wells.

– The primary results are shown below.

– The companies were asked to rank each potential initiative.


Survey of Operatingand Service Companies


• Survey Results− This table shows survey results and priorities.

No. Should the project? Priorities given by fourteen different companies Avg. Rank

Survey Results in Priority Order


• Flow Pattern Behavior– Investigate flow pattern behavior.

– Develop new/improved models for understanding flow and critical rate in horizontal wells.

– The Turner and Coleman methods for estimating critical gas flow velocity in vertical gas wells, and a number of calibrations or mechanistic models for estimating pressure profiles, are not sufficient.

– Primary focus will be to develop new understanding and models for horizontal wells.



• Well Geometry and Trajectory– Make recommendations for well geometry and wellbore

trajectory.

– Many “horizontal” wells are not truly horizontal.

– There may be significant benefits from choosing the “best” wellbore trajectory – toe up, horizontal, or toe down.

– There may be strong reasons to avoid undulations in horizontal wells.

– Evaluate pros and cons of drilling sumps before the wellbore heel to have a vertical or near vertical portion of the wellbore for landing artificial lift equipment.



• Well Design– Focus on well designs such as placement of end of tubing,

location for gas injection, size of casing.

– Evaluate trade-offs between cost of drilling and completing vs. ease of producing wells over time.

– Provide strong evidence to support using casing sizes large enough to accommodate optimal types of artificial lift.

– Guidelines are needed on where to inject gas for gas-lift:• In the vertical part of the well• In the deviated area• At the heel• Along the horizontal portion of the well• At the toe.

– Guidelines are needed on where to place end of tubing.



• Choice of Artificial Lift Method– Focus on choice of “optimum” method of artificial lift for

horizontal wells.

– There are many choices of artificial lift systems.

– ALRDC sponsors industry efforts to develop information and methods to help select the “best” or “optimum” method of artificial lift.

• www.alrdc.com, Recommended Practices, Gas Well Deliquification, Artificial Lift Selection

– Here-to-fore much has focused on vertical gas wells.



• Choice of Artificial Lift Method (continued)– Choices include:

• Chemical systems• Plunger lift• Various types of pumping systems• Various configurations of gas-lift• Other techniques including:

– Wellhead compression– Velocity strings– “Stop cocking” – Downhole water separation and disposal– Vortex creating devices– Various other operating techniques.

– Recommendations and guidelines are needed on which method(s) are most suitable for different horizontal well operating conditions.



• Literature Review– A comprehensive review will be conducted to determine current

“best” practices for artificial lift of horizontal gas and oil wells.

• Other Ideas

– This list is not exhaustive.

– New ideas will be generated as this project unfolds.

– The members of the Consortium will meet at least twice annually to:

• Review progress• Set and/or adjust priorities• Establish new initiatives.

Consortium Membership


• Membership– Membership is open to any Operating, Service/Supply, or

Consulting Company, or University.

– Initial annual membership fee is $50,000.

– The Consortium Advisory Board may change this in the future depending on number of members and amount of work to be done.

– With approval of the University of Tulsa and the Consortium Advisory Board, an equivalent amount of in-kind contributions may be made in lieu of all or part of the membership fee.

– The membership terms are detailed in a letter of agreement which has been supplied to interested organizations and can be made available to anyone else who is interested.

Consortium Membership


• Limitations– No member company may sell, give, or otherwise make results

available to any non-member of the Consortium without the expressed permission of the Consortium Advisory Board.

– Results of the consortium will not be published or released publically until they have passed the University review process.

– This usually requires two years after the information is first provided to the members.

Consortium R&D Plan


• R&D Plan– The priorities listed above will be addressed with four projects.

– Other projects will likely follow as this process unfolds.

– Details of each project are included in the paper.

– Project 1: Understand flow regimes and critical flow rates and investigate multiphase flow behavior in horizontal gas wells.

– Project 2: Investigate artificial lift techniques in horizontal gas wells to assist with:

• Selecting optimum artificial lift method(s).• Placing end of tubing, locating artificial lift equipment (pump,

gas lift), and choosing casing size.• Designing well construction and applicability for various

artificial lift techniques.

Consortium R&D Plan


• R&D Plan (continued)– Project 3: Develop guidelines and recommended practices for

horizontal gas wells.

• Summarize industry learnings and literature information.

• Develop guidelines for when to start artificial lift operations.

– Project 4: Investigate multiphase flow behavior in horizontal oil wells.

Consortium R&D Plan


• Project-1 Deliverables– Understand liquid loading for horizontal wells.

– New liquid loading criteria.

– Experimental data.

– Efficiency of self-unloading.

– Guidance to determine optimum well geometry from unloading perspective.

Consortium R&D Plan


• Project-2 Deliverables– Unloading performance of various artificial lift methods and

their comparative analysis.• Tubing inserts.• Surfactants.• Plungers.• Gas-lift.• Pumping systems.

– Impact of slugging.


– Analysis of setting location of artificial lift equipment.

Consortium R&D Plan


• Project-3 Deliverables– Database consisting of both field and experimental data.

– Analysis of data.

– Guidelines and recommended practices based on field and experimental data.

• Project-4 Deliverables

– Understand oil dominant flow behavior of horizontal wells.


– Model describing flow behavior.

Consortium R&D Plan


• Proposed Project Timetable

Consortium Status


• Current Status– First official meeting held at British Petroleum in Houston,

Texas on Jan. 12, 2012.

– Thirty one people representing twenty one companies attended.

– Of these, six companies indicated they will or are very likely to join the Consortium in the near future.

– Another seven said they are interested but need to review with management.

– Two companies will consider joining on basis of providing services in lieu of paying a membership fee.

– As of now, five companies have joined.

Consortium Status


• Current Status– Efforts will continue over next few months to line up more

members.

– A presentation was made at 2012 Gas Well Deliquification Workshop.

– This presentation is being made at 2012 Southwestern Petroleum Short Course.

– The Consortium will officially begin its work on July 1, 2012.

– The next meeting of the Consortium members will be Summer, 2012, at the University of Tulsa.


Copyright

Rights to this presentation are owned by the company(ies) and/or author(s) listed on the title page. By submitting this presentation to the Southwestern Petroleum Short Course (SWPSC), they grant to the Course rights to:

– Display the presentation at the Course.

– Place it on the Short Course Web Site and the ALRDC Web Site, as directed by the Short Course Committee.

– Place it on a CD for distribution and/or sale as directed by the Short Course Committee.

Other use of this presentation is prohibited without the expressed written permission of the author(s). The owner company(ies) and/or author(s) may publish this material in other journals or magazines if they refer to the Southwestern Petroleum Short Course where it was first presented.


Disclaimer

The following disclaimer shall be included as the last page of a Technical Presentation or Continuing Education Course. A similar disclaimer is included on the front page of the Southwestern Petroleum Short Course Web Site.

The Artificial Lift Research and Development Council and its officers and trustees, and the Southwestern Petroleum Short Course Steering Committee members, and their supporting organizations and companies (here-in-after referred to as the Sponsoring Organizations), and the author(s) of this Technical Presentation or Continuing Education Training Course and their company(ies), provide this presentation and/or training material at the Southwestern Petroleum Short Course "as is" without any warranty of any kind, express or implied, as to the accuracy of the information or the products or services referred to by any presenter (in so far as such warranties may be excluded under any relevant law) and these members and their companies will not be liable for unlawful actions and any losses or damage that may result from use of any presentation as a consequence of any inaccuracies in, or any omission from, the information which therein may be contained.

The views, opinions, and conclusions expressed in these presentations and/or training materials are those of the author and not necessarily those of the Sponsoring Organizations. The author is solely responsible for the content of the materials.

The Sponsoring Organizations cannot and do not warrant the accuracy of these documents beyond the source documents, although we do make every attempt to work from authoritative sources. The Sponsoring Organizations provide these presentations and/or training materials as a service. The Sponsoring Organizations make no representations or warranties, express or implied, with respect to the presentations and/or training materials, or any part thereof, including any warrantees of title, non-infringement of copyright or patent rights of others, merchantability, or fitness or suitability for any purpose.

southwestern petroleum short course lubbock, texas april 18 – 19, 2012 tulsa university horizontal...

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