System and Method for Producing LNG from Contaminated Gas Streams

A system for producing liquefied natural gas (LNG) from methane gas comprising other gaseous components, the system comprising:

• a source of methane gas disposed proximally to a processing site, the source being accessible to the site without transport through an external pipeline;
• a first processing section configured to remove oxygen gas from the methane gas;
• a second processing section configured to remove carbon dioxide from the methane gas;
• a third processing section configured to dehydrate the methane gas;
• a fourth processing section configured to remove nitrogen gas from the methane gas and to liquefy a substantial portion of the methane gas to produce LNG without use of a recirculated refrigerant;
• an LNG subcooler section disposed downstream of the fourth processing section;
• wherein the LNG subcooler section is configured to further cool LNG received from the fourth processing section without use of a recirculated refrigerant;
• conduits through which the methane gas received from the source can flow into and out of the first, second, third and fourth processing sections and the LNG subcooler section;
• and
• a receptacle for LNG received from the LNG subcooler section.

A method for producing liquefied natural gas (LNG) from methane gas containing other gaseous components, the method comprising:

• providing a source of methane gas disposed proximally to a processing site, the source being accessible to the site without transport through an external pipeline;
• introducing the methane gas into a first processing section configured to remove oxygen gas from the methane gas;
• introducing the methane gas into a second processing section configured to remove carbon dioxide from the methane gas;
• introducing the methane gas into a third processing section configured to dehydrate the methane gas;
• introducing the methane gas into a fourth processing section configured to remove nitrogen gas from the methane gas and to liquefy a substantial portion of the methane gas to produce LNG without use of a recirculated refrigerant;
• introducing the LNG received from the fourth processing station into an LNG subcooling section to further cool LNG received from the fourth processing section without use of a recirculated refrigerant;
• and
• introducing LNG received from the LNG subcooler section into a receptacle.