SINTEF Energy Research Compact LNG Heat Exchangers Seminar for NFR sitt Olje og gass program 3 - 4 april 2003 Mona J. Mølnvik SINTEF Energy Research

Compact LNG Heat Exchangers Outline of presentation LNG in general The project Conclusions Spiral Wound LNG heat Exchanger

LNG TRADE Map of major gas trade movements (BP Amoco, 2002)

LNG LNG – Natural gas at –162oC A base-load LNG plant usually comprises the following elements: Inlet facilities CO2 removal Dehydration Natural gas liquefaction LNG storage LNG loading facilities Fractionation

Base Load Plants Existing Baseload LNG plants APCI = Air Products and Chemicals Inc C3/MR = Propane precooled/ mixed refrigerant Cascade = Combined Propane, Ethylene, Methane refrigeration system DMR = Dual mixed refrigerant SMR = Single mixed refrigerant MTPA = Million tonnes per annum

Base Load Plants Current LNG projects MFCP = Mixed Fluid Cascade Process

The coil-wound heat exchanger Produces by: Air Products and Chemicals Inc. in USA Linde in Germany The heat exchangers are made in aluminum. Dimensions of a the main LNG coil-wound heat exchanger is as follows: Height 10-50 m Diameter 3-5 m Core tube diameter 1 m Tube length 70-100 m Tube diameter 10-15 mm The Statoil/Linde MFCP is a more flexible mixed fluid process with two main coil-wound heat exchangers.

The Statoil - Linde Proprietary - Liquefaction Technology MFCP - The Mixed Fluid Cascade Process Novel LNG liquefaction technology Concept based on well known elements Linde fabrication of heat exchangers Plate fin heat exchangers in the precooling Spiral wound heat exchangers in the liquefaction and subcooling

Prosess Barge Hammerfest, Melkøya 2006 4,3 MTPA CO2 reinection

Breakdown of Liquefaction Plant Capital Costs (Finn et al. 1999)

Compact LNG Heat Exchangers Project: 156662/210 Objective: to develop the next generation heat exchanging technology for LNG plants, which compared to heat exchangers used today is: more compact having higher efficiency reduced costs Applicants: SINTEF Energy Research, Norsk Hydro and Statoil (project responsible/manager) Total budget: 14 MNOK (2003-2006), 50% from NFR The project shall lead to a strong international LNG technology position for the project partners by combining: Norsk Hydro’s experience in aluminium multiport extruded tubes and components SINTEF’s experience in gas liquefaction and development of compact automotive refrigeration heat exchangers Statoil’s experience in heat exchanger development and the development of the Hammerfest LNG plant Spiral Wound LNG heat Exchanger

Compact LNG Heat Exchangers Necessity for new technology The propane pre-cooled mixed refrigerant process is the most common refrigerant cycle for base-load natural gas liquefaction plants. Both for future projects and for improvements and replacements on existing plants this configuration will be central. Heat exchange equipment is applied in several parts of a LNG plant. Especially in the liquefaction section, large and expensive equipment is needed. For the liquefaction section the following heat-exchange equipment is of special interest and importance: Condensation of natural gas in the multistream main cryogenic heat exchanger, in heat exchange with evaporating mixed refrigerant Seawater or air cooling of refrigerant in pre-cooling section and mixed refrigerant in the compressor train Cooling of mixed refrigerant and natural gas by evaporating pre-cooling refrigerant Spiral Wound LNG heat Exchanger

Compact LNG Heat Exchangers R&D-challenges The first part of the project will be used to identify which heat exchangers in the LNG process that has the largest potential for improvements regarding size and cost reduction. Material selection - aluminum will put restrictions on possible design due to manufacturing costs and challenges related to corrosion. Performance of enhanced heat exchanger surfaces, heat transfer and pressure drop. Important test data are missing within the field of applications that will be addressed here. Distribution of the two-phase flow in the heat exchanger cores and header systems, an area with major challenges, especially for compact heat exchangers, which is the focus for this project. Spiral Wound LNG heat Exchanger

Compact LNG Heat Exchangers R&D-challenges ... Heat exchanger manufacturing is a challenge since new concepts are to be developed. In this project laboratory heat exchangers will be manufactured and tested based on the experience Hydro inherits from other application areas. Also, two PhD studies are planned; one will be focusing on experimental measurements and new heat exchanger design development. The second PhD will be focused on heat exchanger modeling software development. The project is expected to give results that may contribute to a technological shift within the area of heat exchanger technology for LNG applications. Spiral Wound LNG heat Exchanger

Compact LNG Heat Exchangers R&D-methodology Experimental work Skewed distribution in two-phase flows Heat transfer and pressure drop in advanced compact heat exchangers with enhanced surfaces for improved performance. SINTEF Energy Research and NTNU have large and advanced laboratory facilities and relevant experimental rigs and equipment. Modeling, simulation and software development Based on heat-transfer and pressure drop measurements on advanced heat-exchangers, correlations for use in design and simulation tools will be developed. Development of a design tool for compact heat exchangers for LNG heat exchangers Based on the experimental and modeling activities. An important feature is the wide geometric flexibility in definition and simulation of new designs, both regarding tube configuration and tube and fin geometry. Spiral Wound LNG heat Exchanger

Compact LNG Heat Exchangers Conclusions Coil VV DH = 10 – 15 mm MPE VV DH = 0.8 mm Snøhvit 2? Snøhvit 1