High Pressure High Temperature Multiphase Subsea Cooling - A … Storvik - FMC Kongsberg... · Subsea Flow Line HPHT HPHT Choke XT Cooler • Subsea Cooling enables the use of low(er)

MCE Deepwater Development 2016

PAU, FRANCE • 5-7 APRIL 2016

High Pressure High Temperature

Multiphase Subsea Cooling - A Cost

Reducer for Greenfields, an Enabler for

Brownfields

Mattias Gillis Winge Rudh

FMC Technologies

http://www.google.no/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwi1lNH9y6TLAhVJDJoKHc4gBPUQjRwIBw&url=http%3A%2F%2Fwww.prnewswire.com%2Fnews-releases%2Ffmc-technologies-reports-second-quarter-2015-diluted-earnings-per-share-of-046-300116589.html&psig=AFQjCNFydCd9VXU0P41Q6KMs3bbWiRyO7w&ust=1457097139603954


Subsea Coolers

Hot Fluid In

Cold Fluid Out

Surrounding sea acts as heat sink

Manifold Cooler (Passive)

Typical U-value 600-900 W/m2K

New technology, first installed 2014, Åsgard

Active Cooler


Emerging Technology

Cooling Spool (Passive)

Mature Technology, first installation 1995 East Spar Development


http://www.google.no/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwipx9DmvqTLAhUqEpoKHY8HBFkQjRwIBw&url=http%3A%2F%2Fwww.amazon.com%2FLasko-1827-Adjustable-Elegance-Performance%2Fdp%2FB00FXOFM6U&bvm=bv.115339255,d.bGs&psig=AFQjCNGk7emC92reI-PPTv-E4IMYvmkWFw&ust=1457093579262509


Cooler Equipment

Manifold Cooler Qualification Specimen from the Åsgard Cooler TQP Cooling Loop

Passive Cooler • No moving parts • Robust • Pipe

Active Cooler

Active Cooler • Active transport of sea water (pumping) • Control System • Shell & Tube

http://www.google.no/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjl0bDjjvLLAhXGO5oKHbr8AuAQjRwIBw&url=http%3A%2F%2Fwww.weseng.com.au%2Fprojects%2F&bvm=bv.118443451,d.bGg&psig=AFQjCNHbsT6cB5d8er_tf10111hw8VKrYw&ust=1459760769218034

http://www.google.no/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjTp8SF8_LLAhUjYZoKHTjjAdMQjRwIBw&url=http%3A%2F%2Fwww.kongsberg.com%2Fen%2Fkogt%2Fproducts%2520and%2520services%2Fsubsea%2520products%2520and%2520systems%2Fcooler%2F&bvm=bv.118443451,d.bGg&psig=AFQjCNGay3POHBx8juZtrR9miByOes8pQw&ust=1459787651913406


Cooler Operation

An external flow of sea water is generated by the hot pipes.

From S. Grafsrønningen, PhD Dissertation 2012

Multiphase Flow

Passive Cooler

Msi Kenny Cooling Spool

Active Cooler

An external flow of cooling fluid (sea water) is generated by a pump.

Cooling Fluid (Sea Water)

Multiphase in Multiphase out


Subsea Gas Compression

Gas / Liquid Separation

Enabling lower temperature rated equipment

Subsea Cooler Applications

T

Multiphase Production

Subsea Flow Line

HPHT HPHT

Choke XT Cooler

Subsea Flow Line

T

HPHT HPHT

Cooler Choke XT


T

Subsea Flow Line

HPHT HPHT

Cooler Choke XT

Gas

Liquid

T

HPHT HPHT

Cooler Choke XT

Compressor

Cooler

Gas

Liquid

HPHT HPHT


Subsea Applications – Gas Dehydration

XT Choke

Cooler

T

Subsea Gas Dehydration • 2 Stage separation with in-between

cooling to maximize liquid removal • Gas dehydration (topside glycol

regeneration). • Cooling only on gas stream - > more

efficient cooling design. • Subsea gas export quality

FMC Patented Dehydration Process


Temperature Effect on Subsea Equipment Design

Low Corrosion Rate High Corrosion Rate

Corrosion Rate

Conditions P=40 bar, PCO2=2.7 bar, ID=800mm, QG=6843 Am3/h, QL=130 m3/h

Cathodic Protection

Data from: Schreiber, C.F. and R.W. Murray, "Effect of Hostile Marine Environments on the A1-Zn-In-Si Sacrificial Anode", paper no. 32 Presented at CORROSION/97, March 1988, St.

High temperature Low temperature

Material De-Rating

Source: T.W. Gibbs, W. Kyros, and C.L. Theberge, "Development of a Resistance Heating Facility for the Determination of Tensile Properties of Aircraft and Missile Alloys," RaD. TM-63-8, Avco Corp., Feb 1963. As published in Structural Alloys Handbook, Vol 2, CINDAS/USAF CRDA Handbooks Operation, Purdue University, 1994, p 33

https://icme.hpc.msstate.edu/mediawiki/index.php/File:B2.PNG


Hydrate Formation Some Literature Data Lv, X. F et al Oil and Gas Science and Technology 2015 High Pressure Flow Loop Induction Time 0.5 – 3 hrs F.S. Merkel et al Int. J. Chem. Eng. 2015 High pressure reactor Induction Time 1 – 50 h

Induction Time in a real system? Difficult to say Predictive model fair, Experimental testing required, however for a real subsea system the time scale is probably >> residence time in any subsea cooler!

Typical Hydrate Equilibrium Curve

«Equilibrium between hydrate formation and dissociation»

4CH4 + 23H2O 4CH4 23H2O

A

B

Kinetics of Hydrate Formation

«Driving Force» for hydrate formation

Induction Time Skovborg 1993, Monfort and Nzihou, 1993,

Yousif, 1994, Natarajan, Bishnoi and Kalogerakis, 1994

Lederhos J.P., Long J.P., Sum A., Christiansen R.L., Sloan E.D. Jr (1996) Effective kinetic inhibitors for natural gas hydrates, Chemical Engineering Science 51, 8, 1221-1229

B

A


Wax

R. Venkatesan, Chem. Eng. Sci 60 (2005)

Increasing Cooling rate [°C/s] Cooling Rate B>A • Wax forms when a phase change occurs in long chained

hydrocarbons. • Complex mechanism dependent on composition • Small «contaminants» can have significant impact on the

WAT • Predictive models generally poor, laboratory tests required. • High cooling rate leads to lower wax yield strength.

NIST. 1997. TRC Thermodynamic Tables—Hydrocarbons. College Station, Texas: Thermodynamics Research Center/NIST. Brandrup, J. and Immergut, E.H. ed. 1989. Polymer Handbook, third edition. New York: John Wiley & Sons. Marano, J.J. and Holder, G.D. 1997. General Equation for Correlating the Thermophysical Properties of n-Paraffins, n-Olefins, and

http://petrowiki.org/images/b/bb/Vol1_Page_406_Image_0001.png


Green Field - Case Study #1 – Hot Transport Development of a Gas Condensate HPHT well - Generic Gas Condensate Composition - P=700 bar, T=200°C - 1000m water depth - 5km subsea tie back to host

HPHT WellT=200°C (392°F)

P=700 bar (10152psi)

5km 1000m

XT

Choke15k, 300° F (149°C)

HIPPSCooler

T=149°C (300°F)P=40 bar(580 psi)

T=127°C (260°F)P=39.75 bar(580 psi)

Reducing the temperature upstream the choke enables lower temperature rated choke.

Case #1 – Hot Transport

Insulated flowline


Green Field - Case Study #2 – Cold Transport

Subsea Flowline

Riser

MEG

5km

1000m

Risers

Choke

CoolerHIPPS


P=700 bar (10152psi)

XT

T=31°C (86°F)P=700 bar(10152 psi)

T=4°C (39°F)P=40 bar(580 psi)

T=4°C (39°F)P=39.75 bar(576 psi) Case #2 – Cold Transport

What is most cost effective, continuos MEG injection or insulation?

MEG injection upstream cooler

No insulation, cold transport


Green Field - Case Study #3 – G/L Sep

Subsea Flowlines

Risers

MEG

G/LPump

5km

1000m


P=700 bar (10152psi)

XT

Choke

Cooler

HIPPS

T=31°C (86°F)P=700 bar(10152 psi)

T=4°C (39°F)P=40 bar(580 psi)

• MEG injection upstream cooler • Separating liquid and gas at ambient conditions • Cold transport of liquid and gas • Dedicated liquid and gas transport pipe • No further condensation will occur in the gas line


Comparison – Temperate Effects

The corrosion rate is dependent of the temperature, the CO2 content, wall shear stress and whether the system is saturated be FeCO3 and or the presence of corrosion inhibitors. The effect of adding MEG in Case II and III are incorporated in the corrosion rate calculation. Case I gives the highest corrosion rate.

Corrosion Rate

Case I

Case II / III

By using a higher design temperature the strength of the material needs to be de-rated=thicker pipe walls required for Case I.

De-Rating

Case II / III

Case I

CP design for Case I would require approximately 3 times as large anode mass as for Case II and III compared to Case I.

Cathodic Protection


Cooler Opportunities

Case Comparison When the temperature decrease, the gas volume is reduced and some components condensate. This leads to less frictional pressure drop or a possible increased production while maintaining the same pressure drop.

T

Subsea Flow Line

HPHT HPHT

Choke XT Cooler

Case I - Hot

ΔP, ID = Const

Case II - Cold ΔP, ID = Const

Case III – Cold G/L Sep

ΔP, ID = Const



Gas

Liquid


Favorable for: Corrosion, Mechanical strength, thermal stress, CP system, marine growth, scaling and production.

Favorable for: Hydrate and Wax inhibition

Summary

T


Subsea Flow Line

HPHT HPHT

Choke XT Cooler

• Subsea Cooling enables the use of low(er) temperature rated downstream equipment.

• Subsea Cooling enhance G/L separation. • Subsea Cooling enables subsea compression. • Subsea Cooling enhance gas dehydration. • A low(er) design temperature is favorable for the

hardware design.

http://www.google.no/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwiO5f7Rm67LAhWhJZoKHdUeDkQQjRwIBw&url=http%3A%2F%2Fwww.clipartpanda.com%2Fcategories%2Fthermometer-clip-art-black-and-white&psig=AFQjCNH5mLxt7VBwmu2bO9bOYnH5_5Jf-A&ust=1457427759448193

Documents

High Pressure High Temperature Multiphase Subsea Cooling - A … Storvik - FMC Kongsberg... · Subsea Flow Line HPHT HPHT Choke XT Cooler • Subsea Cooling enables the use of low(er)