Petroleum Petroleum Experts Ltd.Experts Ltd.

Janvier LissanonJanvier Lissanon

Petroleum Petroleum Experts Ltd.Experts Ltd.

Janvier LissanonJanvier Lissanon

Gas Lift Design for a single WellGas Lift Design for a single Well

Understanding individual well performanceUnderstanding individual well performance

Optimized gas lift allocation in a multi-well systemOptimized gas lift allocation in a multi-well system

Gas Lift Design for a single WellGas Lift Design for a single Well

Understanding individual well performanceUnderstanding individual well performance

Optimized gas lift allocation in a multi-well systemOptimized gas lift allocation in a multi-well system

Gas Lift OptimizationGas Lift OptimizationWorkshopWorkshop

Gas Lift OptimizationGas Lift OptimizationWorkshopWorkshop

Gas-Lift ObjectivesGas-Lift ObjectivesGas-Lift ObjectivesGas-Lift Objectives

Maximize the oil production today and Maximize the oil production today and tomorrowtomorrow

Systematic Analysis of individual production Systematic Analysis of individual production system components (well, fluid description, system components (well, fluid description, reservoir response, valve response, pipe line reservoir response, valve response, pipe line behaviour)behaviour)

Allocate the available gas lift volume in a Allocate the available gas lift volume in a multi-well system by taking into account the multi-well system by taking into account the entire network response: entire network response: a non-linear a non-linear optimization problemoptimization problem

Maximize the oil production today and Maximize the oil production today and tomorrowtomorrow

Systematic Analysis of individual production Systematic Analysis of individual production system components (well, fluid description, system components (well, fluid description, reservoir response, valve response, pipe line reservoir response, valve response, pipe line behaviour)behaviour)

Allocate the available gas lift volume in a Allocate the available gas lift volume in a multi-well system by taking into account the multi-well system by taking into account the entire network response: entire network response: a non-linear a non-linear optimization problemoptimization problem

Gas-Lift Design: ObjectivesGas-Lift Design: ObjectivesGas-Lift Design: ObjectivesGas-Lift Design: Objectives

Optimized Gas Lift Design for individual wells:Optimized Gas Lift Design for individual wells:

– Finding the optimum design rate per wellFinding the optimum design rate per well

– Finding the required gas lift gas injection rate and Finding the required gas lift gas injection rate and injection depthsinjection depths

– Finding unloading valves depths, valve trim sizes and Finding unloading valves depths, valve trim sizes and dome setting pressuresdome setting pressures

– Ensuring required design flexibility to changing operating Ensuring required design flexibility to changing operating conditionsconditions

– Check of third party Design (Existing mandrels)Check of third party Design (Existing mandrels)

Optimized Gas Lift Design for individual wells:Optimized Gas Lift Design for individual wells:

– Finding the optimum design rate per wellFinding the optimum design rate per well

– Finding the required gas lift gas injection rate and Finding the required gas lift gas injection rate and injection depthsinjection depths

– Finding unloading valves depths, valve trim sizes and Finding unloading valves depths, valve trim sizes and dome setting pressuresdome setting pressures

– Ensuring required design flexibility to changing operating Ensuring required design flexibility to changing operating conditionsconditions

– Check of third party Design (Existing mandrels)Check of third party Design (Existing mandrels)

Gas-Lift Design: ExampleGas-Lift Design: ExampleGas-Lift Design: ExampleGas-Lift Design: Example

The QuickLook plot: The QuickLook plot: ExampleExample

The QuickLook plot: The QuickLook plot: ExampleExample

Quicklook Example: Quicklook Example: Calibrated ModelCalibrated Model

Quicklook Example: Quicklook Example: Calibrated ModelCalibrated Model

Gas Lift Optimisation in a Gas Lift Optimisation in a multi-well systemmulti-well system

Gas Lift Optimisation in a Gas Lift Optimisation in a multi-well systemmulti-well system

Gas Lift is to be allocated in order to maximise Gas Lift is to be allocated in order to maximise oil productionoil production

Wells, Pipelines and overall System Wells, Pipelines and overall System constraints are to be honouredconstraints are to be honoured

Impact of network response on individual well Impact of network response on individual well performance is to be accounted forperformance is to be accounted for

Gas Lift is to be allocated in order to maximise Gas Lift is to be allocated in order to maximise oil productionoil production

Wells, Pipelines and overall System Wells, Pipelines and overall System constraints are to be honouredconstraints are to be honoured

Impact of network response on individual well Impact of network response on individual well performance is to be accounted forperformance is to be accounted for

Multi-Well SystemMulti-Well SystemMulti-Well SystemMulti-Well System

Gas Injection Rate

Liqu

id R

ate

Gas Injection rate

Liqu

id ra

te

Optimization Techniques in Optimization Techniques in a multi-well systema multi-well system

Optimization Techniques in Optimization Techniques in a multi-well systema multi-well system

The “Equal Slope” MethodThe “Equal Slope” Method

Linear ProgrammingLinear Programming

The The SSequential equential QQuadratic uadratic PProgramming rogramming techniquetechnique

The “Equal Slope” MethodThe “Equal Slope” Method

Linear ProgrammingLinear Programming

The The SSequential equential QQuadratic uadratic PProgramming rogramming techniquetechnique

GL#1: Actual well ResponseGL#1: Actual well ResponseGL#1: Actual well ResponseGL#1: Actual well Response

300

200

100

Gas Lift Gas

Q

First Calculation

Convergence

Starting Point

True Response

Comparison EQ-SLP-LP-SQPComparison EQ-SLP-LP-SQPComparison EQ-SLP-LP-SQPComparison EQ-SLP-LP-SQP

Gas Lift Gas

Q

ES – LP - SLP

SQP Response

∆Q Gas Inj

∆Q Oil

CRITERIAS FOR A CRITERIAS FOR A SUCCESSFUL OPTIMIZATIONSUCCESSFUL OPTIMIZATION

CRITERIAS FOR A CRITERIAS FOR A SUCCESSFUL OPTIMIZATIONSUCCESSFUL OPTIMIZATION

Wells PC must have the network feedback embedded in Wells PC must have the network feedback embedded in their expression (1their expression (1stst and 2 and 2ndnd Derivative) Derivative)

Ability to respect constraints by realistic means Ability to respect constraints by realistic means

Ability to handle mixed systems (NF wells, ESP-wells, Ability to handle mixed systems (NF wells, ESP-wells, gas lifted wells)gas lifted wells)

SQP: SQP:

– non-linear optimization method which accounts for non-linear optimization method which accounts for the entire network response: GAPthe entire network response: GAP

Wells PC must have the network feedback embedded in Wells PC must have the network feedback embedded in their expression (1their expression (1stst and 2 and 2ndnd Derivative) Derivative)

Ability to respect constraints by realistic means Ability to respect constraints by realistic means

Ability to handle mixed systems (NF wells, ESP-wells, Ability to handle mixed systems (NF wells, ESP-wells, gas lifted wells)gas lifted wells)

SQP: SQP:

– non-linear optimization method which accounts for non-linear optimization method which accounts for the entire network response: GAPthe entire network response: GAP

VARIOUS OPTIMIZATION VARIOUS OPTIMIZATION TECHNIQUESTECHNIQUES

VARIOUS OPTIMIZATION VARIOUS OPTIMIZATION TECHNIQUESTECHNIQUES

Equal Slope:Equal Slope:

– works only if no pipeline response is to be accounted for works only if no pipeline response is to be accounted for

– cannot handle constraints in optimized fashioncannot handle constraints in optimized fashion

LP/SLP: LP/SLP:

– can handle constraints but can handle constraints but

– can not optimize non-linear systems like gas lifted systemscan not optimize non-linear systems like gas lifted systems

SQP: SQP:

– Optimization method for Gas Lift Allocation accounting for the Optimization method for Gas Lift Allocation accounting for the entire network responseentire network response

Equal Slope:Equal Slope:

– works only if no pipeline response is to be accounted for works only if no pipeline response is to be accounted for

– cannot handle constraints in optimized fashioncannot handle constraints in optimized fashion

LP/SLP: LP/SLP:

– can handle constraints but can handle constraints but

– can not optimize non-linear systems like gas lifted systemscan not optimize non-linear systems like gas lifted systems

SQP: SQP:

– Optimization method for Gas Lift Allocation accounting for the Optimization method for Gas Lift Allocation accounting for the entire network responseentire network response

SUMMARYSUMMARYSUMMARYSUMMARY

Solid, Consistent and Flexible Gas Lift Design Solid, Consistent and Flexible Gas Lift Design using PROSPERusing PROSPER

Ability to analyse, troubleshoot and quantify Ability to analyse, troubleshoot and quantify the benefit of work-over using PROSPERthe benefit of work-over using PROSPER

Optimize the gas lift allocation in a multi-well Optimize the gas lift allocation in a multi-well system with an optimizer which accounts for system with an optimizer which accounts for the entire network response: GAPthe entire network response: GAP

Solid, Consistent and Flexible Gas Lift Design Solid, Consistent and Flexible Gas Lift Design using PROSPERusing PROSPER

Ability to analyse, troubleshoot and quantify Ability to analyse, troubleshoot and quantify the benefit of work-over using PROSPERthe benefit of work-over using PROSPER

Optimize the gas lift allocation in a multi-well Optimize the gas lift allocation in a multi-well system with an optimizer which accounts for system with an optimizer which accounts for the entire network response: GAPthe entire network response: GAP