Liquid natural gas processing

A process of recovering hydrocarbons heavier than methane from liquefied natural gas (LNG) comprising,

• a) pumping liquid, low pressure LNG to a pressure of greater than 100 psia;
• b) splitting the pressurized liquid LNG from step a) into first and second portions;
• c) directing the first portion of pressurized liquid LNG from step b) to a cold box where it is heat exchanged to increase its temperature;
• d) bypassing the cold box and splitting the second portion of pressurized liquid LNG from step b) into a first reflux and a second reflux;
• e) directing the heat exchanged first portion of pressurized liquid LNG from step c) to a recovery tower where in combination with the first reflux without heat exchange generates a recovery tower overhead and a stabilizer feed;
• f) directing the stabilizer feed to a stabilizer where in combination with the second reflux without heat exchange generates a stabilizer overhead and NGL stream;
• g) directing the recovery tower overhead and the stabilizer overhead to the cold box where they are heat exchanged with the first portion of pressurized liquid LNG;
• h) compressing the heat exchanged recovery tower overhead;
• and
• i) mixing the heat exchanged stabilizer overhead and compressed heat exchanged recovery tower overhead.

A process of recovering hydrocarbons heavier than methane from liquefied natural gas (LNG) comprising,

• a) pumping liquid, low pressure LNG to a pressure of greater than 100 psia;
• b) splitting the pressurized liquid LNG from step a) into first and second portions;
• c) directing the first portion of pressurized liquid LNG from step b) to a cold box where it is heat exchanged to increase its temperature;
• d) bypassing the cold box with the second portion of pressurized liquid LNG and using it as an external reflux in a recovery tower, where in combination with the heat exchanged first portion of pressurized LNG from step c) generates a recovery tower overhead and a stabilizer feed;
• e) directing the stabilizer feed to a stabilizer to generate a stabilizer overhead and a NGL stream;
• f) compressing the recovery tower overhead to form a methane rich stream;
• g) directing the methane rich stream and the stabilizer overhead to the cold box where they are heat exchanged with the first portion of pressurized liquid LNG;
• and
• h) mixing the heat exchanged methane rich stream and stabilizer overhead.

A process of recovering hydrocarbons heavier than methane from liquefied natural gas (LNG) comprising,

• a) pumping liquid, low pressure LNG to a pressure of greater than 100 psia;
• b) splitting the pressurized liquid LNG from step a) into first and second portions;
• c) directing the first portion of pressurized liquid LNG from step b) to a cold box where it is heat exchanged to increase its temperature;
• d) bypassing the cold box with the second portion of pressurized liquid LNG from step b) and increasing the pressure of the second portion to form a stabilizer reflux;
• e) directing the heat exchanged first portion of pressurized liquid LNG from step c) to a separator to generate a separator overhead stream and a stabilizer feed;
• f) directing a first portion of the stabilizer feed to a stabilizer;
• g) heat exchanging a second portion of the stabilizer feed with a stabilizer overhead and feeding the heat exchanged second portion of stabilizer feed to the stabilizer where in combination with the reflux generates the stabilizer overhead and a NGL stream;
• h) heat exchanging the stabilizer overhead with high pressure LNG prior to heat exchanging with the second portion of stabilizer feed;
• j) directing the separator overhead stream and the twice heat exchanged stabilizer overhead to the cold box where they are heat exchanged with the first portion of pressurized liquid LNG;
• and
• i) mixing the heat exchanged separator overhead stream and the stabilizer overhead.

A process of recovering hydrocarbons heavier than methane from liquefied natural gas (LNG) comprising,

• a) pumping liquid, low pressure LNG to a pressure of greater than 100 psia;
• b) splitting the pressurized liquid LNG from step a) into first and second portions;
• c) directing the first portion of pressurized liquid LNG from step b) to a cold box where it is heat exchanged to increase its temperature;
• d) bypassing the cold box and splitting the second portion of pressurized liquid LNG from step b) into a first reflux and a second reflux;
• e) increasing the pressure of the second reflux prior to directing it to a stabilizer;
• f) directing the heat exchanged first portion of pressurized liquid LNG from step c) to a recovery tower to generate a recovery tower overhead and a stabilizer feed;
• g) directing a first portion of the stabilizer feed to the stabilizer;
• h) heat exchanging a second portion of the stabilizer feed with a stabilizer overhead and feeding the heat exchanged second portion of stabilizer feed to the stabilizer where in combination with the second reflux generates the stabilizer overhead and an NGL stream;
• i) heat exchanging the stabilizer overhead with high pressure LNG prior to heat exchanging with the second portion of stabilizer feed;
• j) directing the recovery tower overhead and the twice heat exchanged stabilizer overhead to the cold box where they are heat exchanged with the first portion of pressurized liquid LNG;
• and
• k) mixing the heat exchanged recovery tower overhead and stabilizer overhead.