NGL Recovery Techonolgy at KBR

NGL RECOVERY TECHNOLOGIES Irfan Hussain March 29 - 2011

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What is Gas Processing Introduction to NGL Recovery NGL Recovery Technologies - Joule Thomson Process - Turbo Expansion Process - How Turbo Expander Works

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Licensed Technologies for C2 & C3 Recovery Process Economics for C2 and C3 Recovery Shaybah NGL Recovery Unit Critical Equipment (BAHE)

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Introduction to Gas Processing Acid Gas Removal

Feed from Wellhead

Sulphur Recovery Sulphur Product

Inlet Separation Dehydration Condensate Stabilisation

Gas / LNG Product

NGL Recovery

Condensate Product NGL Product

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Introduction to NGL Recovery What is NGL: • C2 + C3 + C4 mixture (liquefied from gaseous phase) LPG = C3+C4; CNG = C1; LNG = C1 NGL Recovery – Why? • Meet Hydrocarbon Dew Point of sales gas • Extract expansive product (C2/C3) from sales gas

NGL Use • Petrochemical Plants – Polypropylene & Ethylene • Domestic (fuel)

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NGL Recovery (basic schemes) J-T Cooling System

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NGL Recovery (basic schemes) J-T Cooling System – Advantages: - Low Capital Cost - Simplicity of design & operation (no rotating equipment) • Broad range of flow (valves have high turndown capacity) - Can achieve gas dew point by condensate recovery (high revenue) J-T Cooling System – Disadvantages: - NGL recovery may not be feasible if large ΔP is not available - Effectiveness lost as field pressure declines (may require additional equipment) Mechanical Refrigeration can also be used with J-T valve

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NGL Recovery (basic schemes) Turbo Expander Cooling System

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NGL Recovery (basic schemes) Turbo Expander Cooling System – Advantages: - Can be used with medium to high feed gas pressure - Produces work useable as power for sales gas compression - Low gas dew point achievable when low ΔP is available - High revenue with higher NGL recovery Turbo Expander Cooling System – Disadvantages: - Higher capital cost - Extensive gas pre-treatment required to prevent water freezing and solid CO2 formation - Variation in feed gas pressure & composition can reduce efficiency - Special metal alloys in cryogenic area

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How Turbo Expander Works First Law of Thermodynamics Internal Energy can be converted into heat and mechanical work Basic Parts: - Outer housing to contain the gas - Expander wheel connected with a shaft to spin Function: - High pressure (high temp) gas exerts pressure on wheel causing it to turn - Gas exits through a hole in the housing - As gas energy is used to turn the shaft, gas leaves at low temperature & low pressure - NGL is recovered from cold gas - Lean gas is recompressed by the same work (brake compressor) 9

How Turbo Expander Works Isentropic Expansion through Turbo Expander Point (1) is Inlet gas (after treating)

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Point (2) is After cooling by gas/gas exchanger/De-Methanizer side draw coolers 

Dotted Line is new 2 phase diagram after separation of heavier components in LTS 

Point (2) – (3) is Expansion via T.E (work is done by gas i.e. Isentropic Expansion) 

Point (2) – (4) is Expansion via J.T

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Gas can be expanded to lower pressure by T.E than J.T (will recover via B.C) 

At same DP, Lower Temp. is achieved via T.E 

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Licensed Technologies LICENSOR

PROCESS NAME

Gas Subcooled Process (GSP) Single Column Overhead Recycle (SCORE) Overhead Recycle Process (OHR) Cold Residue reflux Process (CRR) Ortloff Engineering Ltd. Recycle Split-Vapour Process (RSV) Recycle Split-Vapour with Enrichment Process Split Flow reflux Process (SFR) Improved Overhead Recycle Process Enhanced NGL Recovery Process IPSI LLC Split Feed Gas Compression Process High Ethane Recovery Process ABB Lummus High Pressure Absorber (HPA) Shell Global Solutions Shell Deep LPG (SHDL)

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Licensed Technologies – C2 & C3 Recovery C3 Recovery Technologies:

Single Column Overhead Recycle (SCORE) Shell Deep LPG Process (SHDL)

C2 Recovery Technologies:

Gas Subcooled Process (GSP) Cold Residue Reflux Process (CRR)

C2 & C3 Recovery using Licensed Technologies 100

96

95

90

100 97

85

80 Recovery, %

99

70 60 50 40 30 20 10

45

43 25 14

0 BTC

Shell SHDL

SCORE

C2 Recovery

C3 Recovery

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GSP

CRR

Licensed Technologies – C3 Recovery Shell Deep LPG

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Licensed Technologies – C3 Recovery Single Column Overhead REcycle (SCORE)

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Licensed Technologies – C2 Recovery Gas Subcooled Process (GSP)

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Licensed Technologies – C2 Recovery Cold Residue Reflux Process (CRR)

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Process Economics for C2 and C3 Recovery Propane Recovery Processes: SHDL & SCORE

95 90 85 80 75 1000

SHDL SCORE

Propane Recovery Processes: SHDL & SCORE 1500

2000

2500

3000

3500

4000 100

Column Pressure, kPa Propane Recovery, %

Propane Recovery, %

100

95 90 85 80

SHDL SCORE

75 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000

Booster Compressor Power, kW

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Process Economics for C2 and C3 Recovery Ethane Re cove ry Proce sse s: GSP and CRR

Ethane Recovery, %

100 90 80 CRR GSP

70 60 1500

2000

2500

3000

3500

4000

100 90 80 CRR GSP

70 60 100,000

110,000

Column Pressure, kPa

120,000

100 80 60 40

CRR GSP

20 0 40,000

130,000

140,000

Total Compression Power, kPa

Ethane Recovery Processes: GSP and CRR Ethane Recovery, %

Ethane Recovery, %

Ethane Re cov ery Processes: GSP and CRR

50,000

60,000

70,000

80,000

Refrigeration Compression Power, kW

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90,000

150,000

Economics – Higher NGL Recovery IS HIGH NGL RECOVERY ALWAYS THE BEST SOLUTION? High NGL Recovery means: Lower sales gas flow Lower gas heating value Higher capital investment Higher operating cost (residue gas compression, refrigeration compressor ) Extra gas treatment required i.e. CO2, moisture removal, Hg removal etc.

Recommendation:  

Detailed life cycle cost analysis to generate maximum revenue Sensitivity analysis for selected process: operating pressures, refrigeration requirement, flow split etc.

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NGL Fractionation

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Open Art NGL Recovery Unit (Pre-Treatment Section) Regen Gas Compressor

Regeneration Gas Separator

Free Water to Drain

Gas Mercury Removal Units

Gas Filter Separators Sweet Rich Gas

Dehydrated Gas to NGL

Gas Molecular Sieve Dehydrators

Feed Gas Chiller

Regen Gas Hot Oil Heater Condensate Mercury Removal Units

Feed Gas Chiller Separators Condensate Filter Separator Liquid Molecular Water Degassing Drum

Sieve Dehydrators

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Dehydrated Condensate to Demethaniser

Open Art NGL Recovery Unit (NGL Recovery Section)

FEED GAS

Demethanizer Overhead BAHE

Feed/Residue BAHE Feed/Side draw BAHE 2

Feed/Residu e BAHE 1 C3 out

To Residue Gas Compressor

Feed/ Residue BAHE 3

Gas Chiller 1

JT Valve

Demethanizer

JT Valve

C3 in From Condensate Mercury Removal Beds Chiller Separator

C3 out

Expander Feed Separator

Turbo Expander /Brake Compressors A/B

To BAHE 3 To BAHE 2

C3 out

Condensate Chiller 1

To BAHE 1

C3 in

heat out

C3 in Condensate Chiller 2 & Gas Chiller 2

Demethanizer Trim Reboiler

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To NGL Surge Spheres

heat in Demethanizer Bottoms Pumps

NGL Recovery Technologies

Shoaib is on Fire !

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QUESTIONS?