System and method for liquefaction of natural gas

A method for producing liquefied natural gas from a natural gas source, comprising:

• fluidly coupling a source of natural gas to an inlet of a heat exchanger;
• feeding natural gas from the source of natural gas to and through the inlet of the heat exchanger;
• feeding a first portion of a single mixed refrigerant from the heat exchanger to a first stage of a first compressor;
• compressing the first portion of the single mixed refrigerant in the first compressor;
• feeding a second portion of the single mixed refrigerant from the heat exchanger to an intermediate stage of the first compressor;
• compressing the second portion of the single mixed refrigerant in the first compressor;
• combining the first portion of the single mixed refrigerant with the second portion of the single mixed refrigerant in the first compressor to produce the single mixed refrigerant;
• condensing at least a portion of the single mixed refrigerant in a first cooler fluidly coupled with the first compressor to produce a first liquid phase and a gaseous phase;
• separating the first liquid phase from the gaseous phase in a first liquid separator fluidly coupled with the first cooler;
• compressing the gaseous phase in a second compressor fluidly coupled with the first liquid separator;
• cooling the compressed gaseous phase in a second cooler fluidly coupled with the second compressor to produce a second liquid phase and the second portion of the single mixed refrigerant;
• separating the second liquid phase from the second portion of the single mixed refrigerant in a second liquid separator;
• pressurizing the first liquid phase in a pump fluidly coupled with the first liquid separator;
• combining the first liquid phase from the pump with the second liquid phase from the second liquid separator to produce the first portion of the single mixed refrigerant;
• feeding the first portion of the single mixed refrigerant and the second portion of the single mixed refrigerant to the heat exchanger to cool at least a portion of the natural gas fed to the heat exchanger from the source of natural gas to produce the liquefied natural gas;
• fluidly coupling a storage tank to an outlet of the heat exchanger;
• and
• feeding the liquefied natural gas into the storage tank through the outlet of the heat exchanger.

A liquefaction system, comprising:

• a heat exchanger including an inlet and an outlet, the heat exchanger configured to receive natural gas through the inlet and cool at least a portion of the natural gas to produce liquefied natural gas;
• a first compressor fluidly coupled with the heat exchanger and configured to compress a first portion of a single mixed refrigerant and a second portion of the single mixed refrigerant from the heat exchanger, and combine the first portion of the single mixed refrigerant with the second portion of the single mixed refrigerant to produce the single mixed refrigerant;
• a first cooler fluidly coupled with the first compressor and configured to cool the single mixed refrigerant from the first compressor to produce a first liquid phase and a gaseous phase;
• a first liquid separator fluidly coupled with the first cooler and configured to separate the first liquid phase from the gaseous phase;
• a second compressor fluidly coupled with the first liquid separator and configured to compress the gaseous phase from the first liquid separator;
• a second cooler fluidly coupled with the second compressor and configured to cool the compressed gaseous phase from the second compressor to produce a second liquid phase and the second portion of the single mixed refrigerant;
• a second liquid separator fluidly coupled with the second cooler and the heat exchanger, and configured to separate the second liquid phase from the second portion of the single mixed refrigerant, and discharge the second portion of the single mixed refrigerant to the heat exchanger;
• and
• a pump fluidly coupled with the first liquid separator and the heat exchanger, and configured to pressurize the first liquid phase from the first liquid separator to combine the first liquid phase with the second liquid phase from the second liquid separator to produce the first portion of the single mixed refrigerant, and
• wherein the outlet of the heat exchanger is connected to feed the liquefied natural gas produced in the heat exchanger into a storage tank.