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LNG TERMINALS. VARIOUS PROCESSES FOR REGASIFICATION. Presentation Frame. Gas Scenario in India LNG Chain What is Regasification? Processes for Regasification of LNG Conclusion. GROWTH OF GAS DEMAND IN INDIA. Large supply deficit Industry using liquid fuels
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LNG TERMINALS VARIOUS PROCESSES FOR REGASIFICATION
Presentation Frame • Gas Scenario in India • LNG Chain • What is Regasification? • Processes for Regasification of LNG • Conclusion
GROWTH OF GAS DEMAND IN INDIA • Large supply deficit • Industry using liquid fuels • LNG import to reduce growing gap • LNG a viable fuel in Indian market Gas Demand (MMSCMD) Source: Report of Working Group (XI Plan) of Government of India
PROJECTED DEMAND - SUPPLY GAP FOR NATURAL GAS Source: Report of Working Group (XI Plan) of Government of India
WHAT IS LNG • LNG Is Natural Gas Liquefied at –160 oC. • NG is liquefied to make it suitable for transportation in LNG ships through sea routes where transportation of NG by pipeline route is not feasible / economical. • During the Liquefaction process NG is purified to very high level. • LNG is therefore environmentally friendly and efficient fuel. • LNG is subsequently regasified at receiving terminal for use by the End users. LNG MOVIE
Liquefaction Loading Transfer Storage Gas Field Transport (Ballasted) Transportation (Loaded) Vaporized LNG to Gas Consumers Pumping Unloading Transfer Regasification Storage LNG CHAIN
LNG TERMINAL BOG COMP. Metering RECONDENSOR UNLOADING/ VAPOR RETURN ARMS LNG Vaporizers LP PUMP HP PUMP SHIP LNG TANK
What is Regasification? It is the process of converting Liquefied Natural Gas in Liquid state to Gaseous state by adding heat.
Types of Vaporizers • Open Rack Vaporizers (ORV) • Submerged Combustion Vaporizers (SCV) • Intermediate Fluid Vaporizers (IFV) • Hydrocarbon Mixture (Rankine Cycle) • Glycol / Methanol Water System • Ambient Air Vaporizers (AAV)
Open Rack Vaporizers (ORV) RLNG Sea Water LNG To Sea The term "open rack" is used because the panels are suspended in a rack, facilitating access for maintenance.
Submerged Combustion Vaporizers Fuel Gas RLNG AIR LNG
Glycol-Water Intermediate Fluid Vaporizer RLNG Air Heater GW Pump Water Collection STV Water to different users Water Pump LNG Glycol Water Circulation
General Weather Conditions at Dahej • Generally warm & Humid Atmosphere • Average Maximum Temperature 37 deg C • Minimum Temperature 13 deg C • Average Temperature 25 to 30 deg C • Humidity 60 to 90 % (avg. 70%) • Sea Water • High Turbidity • High Copper • High Iron ion concentration
SELECTION OF REGASIFICATION SCHEME AT DAHEJ • Open Rack Vaporizers (ORVs) Not Feasible. • Submerged Combustion Vaporizers (SCVs) not desirable. • Advantage of using high ambient temperature.
LNG TERMINAL DAHEJ AIR HEATER Metering STV FUEL GAS SCV GW PUMP STV HW / GW EXCHANGER WATER PUMP FOR BACKUP BLOWER BOG COMP. RECONDENSOR UNLOADING/ VAPOR RETURN ARMS GTG LP PUMP HP PUMP SHIP LNG TANK
AIR HEATERS & STVs –AT DAHEJ 7 STVs / Air Heaters with 112 fans-16.4 MW each Use of SCVs only if ambient heat is in-sufficient (extreme winter months)
Design Issues • Recirculation of Cold air • Generation of Fog • Removal of condensed water
AIR HEATER COMPUTATIONAL ANALYSIS MODEL RESULTS - ORIGINAL CONCEPT
AIR HEATER COMPUTATIONAL ANALYSIS MODEL RESULTS - REVISED CONCEPT Ambient Temp 21 deg C Zero Wind
CONCLUSIONS • USE of STVs & Air Heaters offer most economical & Eco friendly regasification scheme for warm & Humid places • Cold Air Re-circulation cannot be avoided but effect can be minimized by Computational Analysis Modeling • Fogging can be considerably reduced by selecting a layout based on the above analysis