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Emerson Confidential 1

Best Practices For Making Allocation Measurements Using Separators and Multiphase Flowmeter Technology

Jody Overshiner


Agenda

• Why Allocation Measurement is Important • Separator Challenges, Advantages / Disadvantages, Best Practices

• Multiphase Metering Challenges, Advantages / Disadvantages, Best Practices

• Conclusions


Why Are Accurate Allocation Measurements Important?

Measurements may be used to pay royalties to landowners Risk of legal disputes when allocation and sales measurements don’t balance Poor separation efficiency causes lost gas to sales, flaring, metering problems, and frequent trips to the field Difficult to make reservoir and production management decisions with poor data

Inaccurate)Alloca-on)

Measurements)

Reduced)Revenue)


Business Impacts of Poor Allocation Measurement

Up to 30% Differential from

allocation to sales measurement

$360K / year Lost gas to sales due to gas carry

under *

$3.2MM / year Oil lost to water tank due to poor

separation

* 120 wells | 150 BPD | $45 bbl oil | $2.10 gas price


Methods of Allocation Measurement

Alternative method: Inline Multiphase metering

Use MPFM for periodic well testing replacing test separator and keep manifold and production separator

Use dedicated MPFM per well with production separator

Conventional method: Separator

•  Periodic well test with test separator, manifold and production separator

•  Dedicated separator per well

Production Separator

Local Storage

Bulk Separator

Local Storage

Test Separator

Dedicated Separators per Well

Bulk and Test Separators

Manifold

MPFM per Well

Bulk Separator

Centralized Processing & Storage

Manifold

Local Storage

Bulk Separator

Test MPFM and Bulk Separator

Manifold

Test MPFM

Allocation with MPFM at Wellhead to Centralized

Processing


Separator Advantages

•  Has to be done at some point anyway •  Traditional technology

–  Familiar •  Easy to verify performance

–  Can be verified interrogating functional components •  Flexible and can fit in multiple places along the automaton spectrum.

–  Tier 1 •  Displacer level, regulator, pneumatic valves, Coriolis on oil / water, or low

power mag on water –  Tier 2

•  Level Controller / Radar level, regulator, electric actuated valve, Coriolis on oil / water, or low power mag

–  Tier 3 •  Radar level, electric actuated valve, regulator, Coriolis on oil and water,

RTU + separator control


Separator Challenges

• Higher maintenance –  Valves –  Level instruments –  Sand erosion –  Mechanical flow meters

• Sizing –  Changing production rates

• Poor separation can cause –  Water bottoms, oil in water tanks –  Challenges controlling vapors –  Challenges managing inventory

• Higher CAPEX • Larger footprint required


Separator Automation Best Practices

Coriolis Meter

Electric Actuator &

Dump Valve

Guided Wave Radar

RTU Platform

•  Design your automation strategy to fit your needs

•  Select smart flow, level, and pressure instruments to identify and control process upsets

•  Utilize data to understand and optimize separator and well performance

•  Monitor remotely and control with real time event reporting



RTU Configured for Alerts






Methods of Allocation Measurement

Alternative method: Inline Multiphase metering

Use MPFM for periodic well testing replacing test separator and keep manifold and production separator

Use dedicated MPFM per well with production separator

Conventional method: Separator

•  Periodic well test with test separator, manifold and production separator

•  Dedicated separator per well

Production Separator

Local Storage

Bulk Separator

Local Storage

Test Separator

Dedicated Separators per Well

Bulk and Test Separators

Manifold

MPFM per Well

Bulk Separator

Centralized Processing & Storage

Manifold

Local Storage

Bulk Separator

Test MPFM and Bulk Separator

Manifold

Test MPFM

Allocation with MPFM at Wellhead to Centralized

Processing


MPFM Measurement Principle

Fractions

Capacitance / conductance

Density

Velocities

Venturi

Time series / cross correlation Flow rates

Qoil Qwater Qgas


Multiphase Advantages

•  Sizing –  Ability to scale for varying production rates

•  Maintenance Free –  No moving parts

•  Small footprint •  Smart diagnostics

–  Ability to remotely monitor, calibrate, and tune •  Some manufacturers have modular units

–  Utilize individual technology components as required. •  Reduction in HSE •  Reduction in CAPEX and OPEX expenses

–  Can be as much as a 50% reduction in CAPEX –  Can replace test separator and manifold upstream of

Centralized Processing Facility •  Real time continuous monitoring of all three

phases


Multiphase Challenges

•  Still have to separate •  Limited knowledge with the technology

–  Newer than separators –  Initial tuning

•  Requires accurate PVT –  Necessary for accurate measurement, can differ per well

•  Some require Gama components –  May require additional training for compliance

•  Perceived higher cost •  Fiscal allocation

–  Regulatory / Contractual Approvals •  Validation via test separator or master meter


Continuous Monitoring Benefits


Multiphase Best Practices

•  Pay attention to manufacturer’s piping guidelines –  Appropriate isolation valves and procedures

•  Validate fluid densities •  Have experienced personnel for installation and

setup •  Calibrate on recommended intervals •  Consider a fit for purpose modular design

Skid based MPFM

Modular MPFM Design


Summary

•  Separators –  Makes sense on sites with local storage and you have to separate anyway –  Easy to align with automation strategy –  Leverage diagnostics to reduce allocation measurement uncertainty –  Knowledgebase exits

•  Multiphase –  More cost effective for sites where you are only separating for allocation

measurement. –  Smaller footprint and CAPEX and OPEX savings –  Real-time measurement saves time during well testing (more frequent testing) –  Modular design –  Utilize manufacturer’s knowledgebase


Thank You - Questions

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