Cbm Wellsite Facilities - Spe Workshop 2009

SPE APPLIED TECHNOLOGY WORKSHOP (ATW) PRODUCTION MANAGEMENT BEST PRACTICES FOR CBM FIELDS 30 March-2 April 2009 • Queensland, Australia

Coal Seam Gas Wellhead Facilities Some observations & ideas from Australian practice Geoffrey A . McKee +61 407 456 202 SPE Member 3190919

CSG Wellhead Facilities

Overview. . . . What do we mean by “wellhead facilities”? Design. Where do we start? Benchmarks. What do other operators do? Example. One design approach for one project. Some untested new concepts.

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Definition. What are wellhead facilities? Wellhead

Produced water API 3000#

Produced gas API 3000#

Gathering system

Wellhead facilities Basic system:
Mechanical drive for downhole pumps
Fuel gas filter and drier
Gas and water lines and fittings
Gas flow meter (orifice or proprietary)
Safety relief valves on gas & water lines
Control panel including flow computer Possible extra items (if justified): Gas (throttling) control valve?  Remotely operated gas shutdown valve?  Separator for de-gassing water?  Separator for de-watering gas?  Separator for co-mingled water and gas?

Produced water 150#

HDPE

Produced gas HDPE 150#

Above ground Below ground

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Real schematic #1 – basic system

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Real schematic #1. . . . . with separator added for “frothy” water With high water pumping rates:  gas drawn into downhole pumps  problems with gas separating at high points in water gathering system

Produced water downhole pumps (~300 kPag)

Gas from annulus (140 kPag)

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Real schematic #2 - characterised by gas pressure control valve

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Real schematic #3 – comingled gas + water

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Design. Where do we start? 1

2

3

• Design Basis Memorandum (DBM) • Process Flow Diagram (PFD) • Piping & Instrumentation Diagram (P&ID) Order equipment only after step 3 is complete!

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Concept schematic – manual gas throttling

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Concept schematic – remote control

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Concept schematic – frothy water separator added

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Concept schematic – comingled water + gas through separator

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

Concept schematic – comingled water + gas through separator

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Gathering Systems

New concept . . . . . Install nodal separation stations to eliminate wellhead separators VERTICAL SEPARATON TANK (MADE FROM LARGE DIAMETER HDPE GAS PIPE)

TO REDUCE HDPE PIPELAYING COST, WITH FAVOURABLE SLOPING GRADIENT CAN HAVE SINGLE 2-PHASE GAS+WATER LINE FROM SELECTED WELLS

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Wellhead Facilities

New concept . . . . Use of PCPump power for boosting gas pressure of weak wells HIGH PRESSURE WATER (FROM DOWNHOLE PC PUMP

WELLHEAD EJECTOR

2-PHASE HDPE WATER+GAS LINE TO NODAL SEPARATION STATION (NEEDS TO HAVE SLIGHT DOWNWARD SLOPING GRADIENT) VERY LOW POSITIVE PRESSURE (OR VACUUM) IN CASING

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

CSG Gathering Systems & Central Gas Processing Facilities

New concept . . . . . Eliminate inlet & oily water handling at central compression plant

NODAL (INFIELD) COMPRESSION STATION

HEAT EXCHANGER SKID

“DRY” PIPELINE TO CENTRAL PLANT

DX CHILLER PACKAGE*

* IF ELECTRICAL POWER NOT READILY AVAILABLE, USE NH3 ABSORPTION CHILLER POWERED BY COMPRESSOR ENGINE WASTE HEAT

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Production Management Best Practices for CBM Fields, SPE Applied Technology Workshop, Queensland, 30 March - 2 April, 2009

Thank you for listening! Any questions? Coal Seam Gas Wellhead Facilities Some observations & ideas from Australian practice Geoffrey A . McKee +61 407 456 202 SPE Member 3190919