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MIT/NTNU/StatoilHydro PhD Program in Energy and Gas Technology MIT, Boston/Cambridge, 28 29 October 2008 New LNG Proce

MIT/NTNU/StatoilHydro PhD Program in Energy and Gas Technology MIT, Boston/Cambridge, 28 29 October 2008 New LNG Processes & LNG Chains require new Design Methodologies for Subambient Processes by Paul I. Barton Truls Gundersen Chemical Engineering Energy and Process Engineering

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MIT/NTNU/StatoilHydro PhD Program in Energy and Gas Technology MIT, Boston/Cambridge, 28 29 October 2008 New LNG Proce

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  1. MIT/NTNU/StatoilHydro PhD Program in Energy and Gas Technology MIT, Boston/Cambridge, 2829 October 2008 New LNG Processes & LNG Chains require new Design Methodologies for Subambient Processes by Paul I. Barton Truls Gundersen Chemical Engineering Energy and Process Engineering MIT, Boston NTNU, Trondheim USA Norway Paul I. Barton & Truls Gundersen

  2. Brief Outline • Motivation • Project Proposal • History • Prior collaboration MIT/NTNU • Results so far • Publications • The Liquefied Energy Chain (LEC) • The ExPAnD Methodology • Combining Thermodynamics & Optimization • Optimization Formulations and Algorithms Paul I. Barton & Truls Gundersen

  3. Motivation • Increased importance of Natural Gas and LNG in the World and in Norway • A Number of Current and Future Challenges in LNG (and Natural Gas) • Significant Limitations in Existing Design Methodologies and Tools for LNG and Subambient Processes Paul I. Barton & Truls Gundersen

  4. Coal Natural Gas Oil Natural Gas increases in Importance Paul I. Barton & Truls Gundersen

  5. LNG increases even more Ref.: http://www.cedigaz.org/Fichiers/PREstimates2006.pdf Paul I. Barton & Truls Gundersen

  6. Challenges for the LNG Industry • New ways to utilize Stranded Natural Gas • Trend towards (flexible) Floating LNG Chains • Will need CCS from fossil based Energy Systems • Capturing CO2 will drastically change Heat/Power ratio • Future Large Scale use of Amines has a considerable Economic Penalty; it may have an Environmental Penalty • How to deal with larger H2S and CO2 fractions? • Could Cryogenic Distillation (Ryan-Holmes) be used? • Effects of breakthroughs in Equipment Design • Synergies in co-localization with Industrial Cluster  Need new Process Concepts and Chain Configurations Paul I. Barton & Truls Gundersen

  7. Limitations of Existing Methodologies • Pinch Analysis (PA) has been extensively used in the Process and Energy Industry for 25 years to Design: • Heat Exchanger Networks with focus on • Heat and Power Systems Energy Efficiency • Distillation Systems, etc. and Economy • Major Limitations of PA in Subambient Processes • Only Temperature is used as a Quality Parameter • Exergy Considerations are made through the Carnot Factor • Pressure and Composition are not Considered • Exergy Analysis and 2nd Law of Thermodynamics • Considers Temperature, Pressure and Composition • Focus on Equipment Units, not Flowsheet (Systems) Level • No strong Link between Exergy Losses and Cost • Often a Conflict between Exergy and Economy Paul I. Barton & Truls Gundersen

  8. Why is Pressure important Subambient? • Pressure is significant in Process Integration efforts to reduce Energy Requirements above Ambient • Defines the Level ( T) of large Heat Duties ( Q ) • Often defines the Heat Recovery Pinch • Pressure is even more important below Ambient • In Phase changes, Temperature is linked to Pressure • In Pressure Changes, Temperature is linked to Power • Subambient Cooling (Refrigeration) is provided by Compression, thus Pressure is again important • Pressure can be ”traded” against Cooling • A pressurized Cold Stream below Ambient can be expanded to provide Additional Cooling (and some Power) • Pressure Exergy can be converted to Temperature Exergy Paul I. Barton & Truls Gundersen

  9. Project Proposal • ”Optimal Design of LNG Processes and Production Chains  Developing new Methodologies and Tools for Subambient Processes”  (2009-2012) • Supported by StatoilHydro (LoI) • Application pending with the RCN • Budget and Manpower • 8 mill. NOK total over 3 years (1.3 mill. USD) • 2 PhD’s (3 years) & 2 Post.doc’s (2 years) • Existing Groups & Related Topics • Paul I. Barton & 2 PhD’s (A. Selot & E. Armagan) • Truls Gundersen & 2 PhD’s (A. Aspelund & R. Anantharaman) • Research Strategy: Simultaneous Development of new Process Concepts and Design Methodologies Paul I. Barton & Truls Gundersen

  10. History of Collaboration  Barton / Gundersen • Informal collaboration since 2005 • Joint Project Proposal for the 1st Call MIT/NTNU October 2005 • PhD Student Audun Aspelund at MIT Fall 2006 & Spring 2007 • Four Results have emerged in Parallel • A Liquefied Energy Chain (LEC) for Stranded Natural Gas • An Extended Pinch Analysis and Design (ExPAnD) Procedure • A Math Progr. Model for Optimizing Temperatures and Pressures • A Simulation-Optimization Approach for Entire LNG Chains • Publications • 1 Patent on the LEC (industrialization attempted through TTO) • Journal Papers: • 1 published (ExPAnD), 4 (series) accepted (LEC), 1 drafted (Opt. P/T) • Conference Contributions: • CHISA/PRES 2006, ESCAPE 2007, AIChE Mtg 2007, INFORMS 2007 • 1st Gas Symposium, Qatar, 2009 (2 papers accepted) Paul I. Barton & Truls Gundersen

  11. OXYFUEL Process CO 2 LNG LNG LNG Water NG Power S Process NG LNG LNG t Electricity The o The Offshore r Onshore O 2 N 2 LIN LIN Process a Process g CO 2 LCO 2 LCO 2 N 2 e ASU Argon LIN LCO 2 LCO 2 AIR The Liquefied Energy Chain (LEC)- Utilize Stranded Natural Gas for Power Production- Combined with CO2 Capture and Storage- Enhanced Oil Recovery using CO2- Combined Liquid Carrier Paul I. Barton & Truls Gundersen

  12. The ExPAnD Methodology • Extended Pinch Analysis and Design • Currently focusing on Subambient Processes • A new Problem Definition has been introduced: • ”Given a Set of Process Streams with a Supply and Target State (Temperature, Pressure and the resulting Phase), as well as Utilities for Heating and Cooling  Design a System of Heat Exchangers, Expanders and Compressors in such a way that the Irreversibilities (or later: TACs) are minimized” • Limitations of the Methodology (at present) • Relies Heavily on a Set of (10) Heuristics, 6 different Criteria (Guidelines) and suffers from a rather Qualitative Approach • Strong need for Graphical and/or Numerical Tools (Optimization) to replace or assist Heuristic Rules and Design Procedures • Using the Concept of Attainable Region is a small Contribution towards new Graphical and Quantitative ExPAnD Tools Paul I. Barton & Truls Gundersen

  13. Target State Supply State Temperature/Enthalpy (TQ) ”Route”from Supply to Target State is not fixed The Route/Path from Supply to Target State is formed by Expansion & Heating as well as Compression & Cooling a) Hot Streams may temporarily act as Cold Streams and vice versa b) A (Cold) Process Stream may temporarily act as a Utility Stream c) The Target State is often a Soft Specification (both T and p ) d) The Phase of a Stream can be changed by manipulating Pressure The Problem is vastly more complex than traditional HENS Paul I. Barton & Truls Gundersen

  14. Heating before Expansion Expansion before Heating Heating only How can we Play with Pressure? Given a ”Cold” Stream with Ts = - 120ºC, Tt = 0ºC, ps = 5 bar, pt = 1 bar Basic PA and the 2 ”extreme” Cases are given below: 159.47ºC -176.45ºC Paul I. Barton & Truls Gundersen

  15. How can we Play with Pressure? Given a ”Cold” Stream with Ts = - 120ºC, Tt = 0ºC, ps = 5 bar, pt = 1 bar Attainable Region with One Expander: Paul I. Barton & Truls Gundersen

  16. O2 Air Separation ASU Oxyfuel Power Plant W Air NG LNG LIN H2O NG LNG Natural Gas Liquefaction CO2 Liquefaction CO2 LCO2 Sub-processes in the LEC Illustrate how ExPAnD is used to design the Offshore Process Paul I. Barton & Truls Gundersen

  17. Base Case for the Offshore Process- using basic Pinch Analysis Heat Recovery first, Pressure Adjustments subsequently Paul I. Barton & Truls Gundersen

  18. Seawater NG CO2 ex = 49.7 % LNG N2 Base Case Composite Curves External Cooling required for Feasibility External Heating is ”free” (Seawater) Paul I. Barton & Truls Gundersen

  19. ex = 85.7 % After several Process Modifications The Composite Curves have been ”massaged” by the use of Expansion and Compression Paul I. Barton & Truls Gundersen

  20. N 2 - 7 EXP - 101 K - 101 N 2 - 8 N 2 - 9 N 2 - 4 EXP - 102 N 2 - 5 N 2 - 10 N 2 - 12 N 2 - 11 N 2 - 6 N 2 - 3 CO 2 - 4 N 2 - 2 N 2 - 1 CO 2 - 3 CO 2 - 2 NG - 5 NG - 2 NG - 3 NG - 4 NG - PURGE P - 101 P - 102 NG - 1 NG - 6 K - 100 V - 101 LIQ - EXP - 101 LIQ - EXP - 102 CO 2 - 1 P - 100 LNG A novel Offshore LNG Process Self-supported w.r.t. Power & no flammable Refrigerants Paul I. Barton & Truls Gundersen

  21. The Nitrogen ”Path” Paul I. Barton & Truls Gundersen

  22. ex = 71.2 % The Onshore Process (Regasification) Paul I. Barton & Truls Gundersen

  23. More new Process Concepts? • The LNG Industry is facing several Challenges • We will Challenge established ”Truths” about LNG • The Trend has been to shift from Cascaded Single Component Refrigerants to Mixed Refrigerants • Cascade Liquefaction Processes • Mixed Refrigerants • Mixed Refrigerants cause Flow Distribution Problems in Heat Exchangers Onshore, even more so Offshore • We have shown that Multicomponent Behavior can be achieved by Single Components playing with Pressure • Expansion & Compression Paul I. Barton & Truls Gundersen

  24. Cascade Liquefaction Process Paul I. Barton & Truls Gundersen

  25. Combining Mixed and Pure Refrigerants APCI’s C3-MR dominates (≈ 87%) Paul I. Barton & Truls Gundersen

  26. N 2 - 7 EXP - 101 K - 101 N 2 - 8 N 2 - 9 N 2 - 4 EXP - 102 N 2 - 5 N 2 - 10 N 2 - 12 N 2 - 11 N 2 - 6 N 2 - 3 CO 2 - 4 N 2 - 2 N 2 - 1 CO 2 - 3 CO 2 - 2 NG - 5 NG - 2 NG - 3 NG - 4 NG - PURGE P - 101 P - 102 NG - 1 NG - 6 K - 100 V - 101 LIQ - EXP - 101 LIQ - EXP - 102 CO 2 - 1 P - 100 LNG Pure Refrigerants & Expansion/Compression Paul I. Barton & Truls Gundersen

  27. ex = 85.7 % Pure Refrigerants & Expansion/Compression Q: Can these Results from the Offshore Process be utilized in Onshore LNG Applications ? Paul I. Barton & Truls Gundersen

  28. Why do we need Optimization? • The Heuristics of ExPAnD coupled with Domain and Engineering Insight can produce Thermodynamically “sound” and “near-optimal” Processes, however . . . • Multiple Economic Trade-offs requires Optimization • Optimization can be used in a number of Ways • At the total Energy Chain Level (including Ship Utilization) • At the Level of the individual Processes of the Chain • Optimize Decisions at the Flowsheet Level (structure) • Optimize Operating Conditions (flows, compositions, P and T) • Different Optimization Algorithms can be used • Deterministic Methods (Mathematical Programming) • Stochastic Methods (Simulated Annealing, Genetic Algorithms, etc.) Paul I. Barton & Truls Gundersen

  29. and by that it is time to introduce my Project Partner Prof. Paul I. Barton Paul I. Barton & Truls Gundersen

  30. Paul I. Barton & Truls Gundersen

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