220 likes | 843 Views
?. LIQUEFIED NATURAL GAS CARRIER (LNG). What is LNG ?. Lique Natural Gas. fied. O. Natural Gas. Natural Gas. At Minus 260 Fahrenheit (-162 C). O. Reduces to 1/600 of its original volume. Vessel insulation is crucial !. Membrane type LNG carrier tank layers of insulation.
E N D
? LIQUEFIED NATURAL GAS CARRIER (LNG)
What is LNG ? Lique Natural Gas fied O Natural Gas Natural Gas At Minus 260 Fahrenheit (-162 C) O Reduces to 1/600 of its original volume Vessel insulation is crucial !
Membrane type LNG carrier tank layers of insulation Then 4 layers of insulation BALLAST WATER The membrane is where there have been “gluing” problems OUTER HULL INNER HULL 1.8 metres (6 feet) 2nd layer Insulation 2nd Membrane 1st Membrane 1st layer Insulation
So where are all the reserves of natural gas then ? Known reserves at 1 Jan 2011 Source: http://www.aneki.com/countries2.php?t=Countries_with_the_Largest_Natural_Gas_Reserves&table=fb167&places=*=*&order=desc&orderby=fb167.value&decimals=--&dependency=independent&number=all&cntdn=asc&r=-67-68-69-70-71-72-73-74-76&c=&measures=Country--proven%20reserves%20of%20gas%20%28cu%20m%29&units=--&file=gas
There are 2 methods for transporting the gas ….or a combination of both… …. by pipeline … ….or by sea…
..and the ships get bigger and bigger MEMBRANE TYPE PRISMATIC (Q - Max) TYPE MOSS-ROSENBURG TYPE Tanks fully incorporated into the ship’s hull Tanks independent of the ship’s hull
Loading, carriage and discharging LNG carriers Cryogenic hose Natural gas is cryogenically liquefied into LNG on-shore Transferred from shore to vessel LNG PLANT 1) Directly at the terminal 2) Offshore at a buoy mooring On board, LNG kept at boiling point (-162°C) to deliberately allow some “boil off” Discharging is done EITHER :- as LNG using cryogenic hoses (as with loading) “Boil off” TEMPERATURE ….. or by allowing LNG to vaporise on board (and then pumping as a gas) Heat Heat STORAGE TANK
What is L G ? P Liquefied Petroleum Gas Liquefies at Odour added Propane (C3H8) -42 ºC Ethanethiol (CH3CH2SH) Butane (C4H10) -0.5 ºC The greater the % of propane in the LPG, the more pressurized (or lower temperature) it needs to be, to remain liquefied % of butane in the LPQ Pounds per square inch pressure required Temperature (C) Source: http://www.engineeringtoolbox.com
Carriage of LPG Semi-pressurized, semi-refrigerated ships have a cargo carrying capacity of 5,000 cubic metres under temperature and pressure condition of -10 degree Centigrade and 8.5 kg/ cm2 respectively. Larger vessels can carry at temperature of -48 degree Centigrade. As the boiling point of LPG is much higher than LNG, a re-liquefaction plant on the ship can load the cargo as gas and liquefy it onboard. Heating and cooling facilities are also provided for smooth discharging of the cargo
LNG CARRIER INSURANCE ISSUES Current cost to build between $180,000,000 - $290,000,000 (152,000 cu.m.) (270,000 cu.m.) BILL $22,000,000 + “Sloshing” Damage Claims BILL $35,000,000 + Containment Systems Claims Has led to Total Loss Insulation adhesive weakness claims The only yards with repair capability……. ……are too busy building new ones !
L.N.G. Carriers Just one of 10 vessel types covered by Steve Harris during the Marsh Marine Insurance Weeks For more information or a brochure, contact Marion J. Paul, Marsh Norwich U.K. Tel: + Intl 44 (0)1603 207098 E-mail: Marion.J.Paul@marshoperations.co.uk