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LNG Measurement

LNG Measurement. Jim Gray Flow Solutions Advisor. Some LNG History. The world’s first large shipment of LNG occurred in1964 in Algeria Prior to 1964, natural gas in Algeria was deemed a waste product

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LNG Measurement

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  1. LNG Measurement Jim Gray Flow Solutions Advisor Emerson Confidential

  2. Some LNG History • The world’s first large shipment of LNG occurred in1964 in Algeria • Prior to 1964, natural gas in Algeria was deemed a waste product • LNG is now exported from locations such as: Qatar, Algeria, Egypt, Nigeria, Angola, Oman, Yemen, Russia, Trinidad and Tobago, Australia, Malaysia, and Indonesia …..

  3. Key cost impacts in the LNG market • Many technical innovations in LNG liquefaction and shipping • 67% reduction in the cost of liquefaction component and 42% reduction in construction costs of ships are key components • Substantially lower shipping cost by replacing traditional steam turbine engines by gas powered propulsion systems resulting in reducing fuel costs and increased cargo capacity • Huge additional cost reduction with utilizing a “Common LNG” operating philosophy by Qatar Gas Plant • One cubic metre of LNG has a typical sales value of $342 which has the impact shown below Emerson Confidential

  4. LNG Measurement • The primary measurement of LNG is Energy value • Also required are Volume, Mass, Density, and Gross Calorific Value • For correct overall measurement Boil Off Gas (BOG) requires metering during all LNG movement, except latest Q Max tankers which have their own BOG recovery system • With modern LNG tankers gas consumed as fuel source for the LNG tanker engines is also required to validate the correct LNG mass balance Emerson Confidential

  5. Two Primary Approaches to LNG Volume Measurement • Static Measurement (Current Approach) • Tank Gauging (Shipboard and Onshore Storage) • Dynamic Measurement (New Approach) • Flow Metering • Both approaches have potential scope for improvement • Tank Gauging - More research is required with regard to the true uncertainty of method of previously widely used historical tank gauging systems • Flow Metering - Establishment of an international measurement standard is required to support the higher performance solution of dynamic metering of LNG Emerson Confidential

  6. LNG Overview • LNG is predominantly methane that has been cooled to below -160°C at atmospheric pressure whose volume contracts by about 620 times. • Generally processed from Lean Natural Gas • Natural gas is liquefied at an export terminal and is then transported to import terminals in large purpose built ships. The LNG is then regasified at a plant at the import terminal for supply to the national distribution network • Measurement of the quantity of LNG delivered to or received from a ship’s tanks is currently made in the form of energy transferred* The G.I.I.G.N.L. (International Group of Liquefied Natural Gas Importers) Handbook reports inaccuracies involved in the measurements of the parameters given in equation (1) above and the overall inaccuracy in determining the LNG energy transferred. *Source: Flow Measurement Guidance Note No. 53 Liquefied Natural Gas Flow Measurement Technologies. NEL, East Kilbride, UK

  7. Evaluation of Dynamic Flow Measurement • A jointly funded evaluation project was launched by 3 of the major IOC’s prior to detail engineering for a LNG project • The qualification tests were performed at a LNG plant located in Kenai, Alaska 11 years ago • The basic pre-qualification requirements that resulted in choosing Ultrasonic and Coriolis meter technologies for evaluation were as follows: • No wetted or rotating parts • No external tubing required • Improved surveillance via advanced diagnostics • Proven reliability • Documented accuracy in liquid custody transfer applications • Reduced annual maintenance • Operational Expenditure savings • Results from these tests demonstrated repeatability of better than ±0.125% for both USM and Coriolis measurement technologies. A key result from this research was the agreement of the two technologies calibrated in different ways to < 0.1%, (3 times better than the on-site validation method) • Above represents a significant improvement in uncertainty of method relative to Tank Gauging for LNG measurement Emerson Confidential

  8. International Oil Co.’s Uncertainty Review of GIIGNL LNG level standard

  9. Overcoming The Challenges of LNG Tank Gauging • Emerson is one of very few companies in the world that can supply complete LNG tank gauging inventory solutions. The Raptor LNG storage management system from Emerson provides you with highly reliable inventory and rollover prediction data including: • Level • Liquid temperature • Density • Temperature profiles • High-level alarm • Skin temperature measurement • Cool down control and leak detection Emerson Confidential

  10. LNG Export Facility-Conventional Measurement Configuration Legend • L/T – radar/level based instrumentation + sampling • m – allocation meters • M – fiscal meters • BOG – Boil Off Gas • S – Sample point BOG FLARE P FUEL m LNG Tanker m L/T LNG Plant BOG LNG Tank L/T M S

  11. LNG Export facility - In-line Measurement Configuration Legend • L/T – level/temperature instrumentation + sampling • m – allocation meters • M – fiscal meters • BOG – Boil Off Gas • S – Sample point BOG m FLARE P FUEL m m L/T LNG Tanker BOG LNG Plant m LNG Tank L/T M S m M

  12. Upstream LNG Ultrasonic Meters Emerson Confidential

  13. Approach to Dynamic LNG Measurement • Dynamic measurement is the determination of volumes using a flow meter at a designated metering point; typically loading / offloading / rundown lines • Measuring the flow rate of LNG volume requires • Primary element flow meter • Upstream meter runs • P&T instrumentation • Calibration or proving methodology

  14. Emerson 3818 LNG Ultrasonic Flowmeter 3818 LNG Cryogenic Flow Meter • For custody transfer or check measurement • Lower uncertainty than level measurement • Negligible pressure drop • Full bore non-intrusive ultrasonic • Minimal risk of liquid flashing • Low maintenance • No moving parts • Can repair on site • Inherent design redundancy • Remote diagnostics • Correction for changes in meter geometry due to temperature Isolated Electronics Insulation Package Welded Transducer Holders Low temperature transducers for cryogenic applications to -190ºC

  15. Zero Flow Testing on Liquid Nitrogen Emerson Confidential

  16. NMI Custody Certification • Model 3814 and 3818 approved for accuracy class 0.3 • Temperature range -200ºC to +150ºC • For measurement of: • Liquid petroleum and related products • Chemical products in liquid state

  17. Gorgon LNG Plant End User: Chevron Partners: Exxon Mobil Destination: Australia Project: Gorgon LNG Scope: 2 x 30” Model 3818 (LNG loading) 6 x 30” Model 3812 (Amine Treater) 9 x 20” Model 3414 (Raw Gas Inlet) Overview: LNG plant, condensate handling facilities, carbon dioxide injection facilities and associated utilities

  18. LNG Coriolis Meters Emerson Confidential

  19. LNG Measurement Philosophy • LNG is traditionally traded on the basis of long-term contracts. Volume measurement relies on tank gauging • Calibration tables • Corrections for list, trim, tank contraction, level device … • In future, LNG will also be traded on short term (spot) contracts typically representing smaller volumes • Dynamic measurement in transfer lines per typical custody transfer systems can provide accurate volume measurement of these smaller quantities Emerson Confidential

  20. Micro Motion for LNG Custody Transfer • 20+ years of experience in flow metering of cryogenic and LNG applications • Existing CT Approvals and Proven Track Record • 3rd Party NIST and CERN Certified performance on cryogenic flows • Existing ATEX approvals for -194C • Numerous installed references on LNG Custody Transfer including APA/GasNet loading application in Australia • Micro Motion Patented Temperature Coefficient Curves for cryogenic applications • Only Coriolis meter with 3rd Party verified water calibration transferability of flow calibration factor to cryogenic fluids. (Uncertainty < ± 0.3%) • Direct correlation of Energy to Mass • Vapor Entrainment measurement capability Emerson Confidential

  21. Micro Motion, NMI Evaluations to OMIL R117, R137, and R81 • Certificates of Approval • Gases • Liquids (oil, oil products, alcohol, chemicals, potable liquids, liquefied gases under pressure (NGL and LPG) • Ethylene • Cryogenic fluids • Class 0.3 on liquids 1/10” to 10” flow area • Conditions of Conformity Assessments • Water Calibration • Meter zero, Flow Cal Factor, Density Cal • Field Startup • Meter zero check • Density check • “Procedure is justified because tests on Micro Motion Meters have proven that mass accuracy on water is representative for mass accuracy on other liquids”

  22. Determining LNG Density and Gross Calorific Value • Direct measurement using densitometers is not normally used on LNG • Density is derived from gas composition and equations of state (e.g. Modified Klosek – McKinley model) • Sampling LNG for a reliable sample is the key component in deriving calorific value • Taking a representative sample • Vaporization of the fluid • Conditioning of the gas • Transportation to the analyzer • Sampling and determination using a GC is common to traditional and new methods of measuring LNG. Emerson Confidential

  23. LNG Metering Skid Design Challenges Due to the High Thermal Expansion from ambient to -161°C operating temperature, means “conventional” skid layout designs cannot be used. Side entry and exit points at opposite corners Stream expansion loops Skid mounted inlet and outlet headers with meter runs on special pipe supports Special multi layer / material on the insulation required Remote vents and drains

  24. New LNG Terminal in Stockholm/Nynäshamn Year 2011 • Storage capacity: • 20.000 m3 • 9.260 ton • 126 GWh • Energy capacity/year: 3 TWh Emerson Confidential

  25. Ship Unloading Micro Motion HC3 meter

  26. Blending Micro Motion CMF200 meters

  27. Truck loading Micro Motion CMF300 meters

  28. CRYO STAR in BOC Tassie Australia – LNG off Loading Emerson Confidential

  29. LNG Dispensing Solution • Calibration Independent of fluid properties and operating conditions • High error immunity to installation effects and flow disturbances • Robust compact design with no moving parts and on-line diagnostics • On-line density and temperature Results • Long-term performance trends between +/- 0.1 to 0.05% • On-line diagnostics • Safety – mechanical integrity • Vapor / two phase detection Emerson Confidential

  30. Conclusion • Improved total system uncertainty on LNG by utilising dynamic measurement • Comparison between TG & dynamic measurement highlights the improved performance that can be achieved with dynamic measurement, especially if both are provided as a fully integrated solution on this high value product • A large capacity LNG calibration facility, together with the release of a new ISO standard for dynamic measurement, will further accelerate the adoption of dynamic measurement • We intend to increase our investment on all measurement aspects of LNG measurement • We look forward to the opportunity of sharing our experience and knowledge of LNG metering Emerson Confidential

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