Low-temperature mixed-refrigerant for hydrogen precooling in large scale

A method of liquefying a feed gas stream, the method comprising:

• providing a feed gas stream comprising a gas wherein said gas is hydrogen or helium, and wherein said feed gas stream has an initial temperature,
• precooling said feed gas stream from said initial temperature to an intermediate temperature in a precooling step by a closed loop cooling cycle with a precooling refrigerant stream yielding a precooled feed gas stream,
• cooling said precooled feed gas stream in a cooling step from said intermediate temperature to a temperature below the boiling temperature or the critical temperature of said gas,
• wherein said preceding refrigerant stream comprises a refrigerant composition selected from the following compositions (a), (b), and (c):
• composition (a) consisting of:
• a first component, a second component, a third component, and a fourth component, wherein
• said first component is nitrogen in the range of 5 mol. % to 35 mol. %,
• said second component is argon in the range of 20 mol. % to 40 mol. %,
• said third component is ethane or ethylene in the range of 10 mol. % to 40 mol. %, and
• said fourth component is one of isobutane, isopentane or 1-butene in the range of 10 mol. % to 35 mol. %, or propane or propylene in the range of 10 mol. % to 45 mol. %,
• provided that the sum of the concentrations of the components does not exceed 100 mol. %;
• composition (b) consisting of:
• a first component, a second component, a third component, a fourth component, and a fifth component wherein
• said first component is nitrogen in the range of 5 mol. % to 35 mol. %,
• said second component is argon in the range of 20 mol. % to 40 mol. %,
• said third component is ethane or ethylene in the range of 10 mol. % to 45 mol. %, and
• said fourth component is one of isobutane, isopentane or 1-butene in the range of 10 mol. % to 35 mol. %, or propane or propylene in the range of 10 mol. % to 45 mol. %, and
• said fifth component is one of n-butane, isobutane, propane, propylene, n-pentane and isopentane, wherein said fifth component is different from said fourth component, provided that the sum of the concentrations of the components does not exceed 100 mol. %;
• and
• composition (c) consisting of:
• a first component, a second component, a third component, a fourth component, a fifth component, and a sixth component wherein
• said first component is nitrogen in the range of 5 mol. % to 35 mol. %,
• said second component is argon in the range of 20 mol. % to 40 mol. %,
• said third component is ethane or ethylene in the range of 10 mol. % to 40 mol. %, and
• said fourth component is one of isobutane, isopentane or 1-butene in the range of 10 mol. % to 35 mol. %, or propane or propylene in the range of 10 mol. % to 45 mol. %, and
• said fifth component is one of n-butane, isobutane, propane, propylene, n-pentane and isopentane, wherein said fifth component is different from said fourth component, and
• said sixth component is one of n-butane, isobutane, propane, propylene, n-pentane and isopentane, and wherein said sixth component is different from said fourth component and said fifth component,
• provided that the sum of the concentrations of the components does not exceed 100 mol. %.

A method for liquefying a feed gas stream, the method comprising:

• providing a feed gas stream comprising a. gas wherein said gas is hydrogen or helium, and wherein said feed gas stream has an initial temperature,
• precooling said feed gas stream from said initial temperature to an intermediate temperature in a precooling step by a closed loop cooling cycle with a precooling refrigerant stream yielding a precooled feed gas stream.
• cooling said precooled feed gas stream in a cooling step from said intermediate temperature to a temperature below the boiling temperature or the critical temperature of said gas,
• wherein said precooling refrigerant stream comprises a refrigerant composition consisting of a first component, a second component, a third component, and a fourth component, wherein:
• (a) said first component is nitrogen in an amount of 8 mol. % to 18 mol. %,
• said second component is methane in an amount of 30 mol. % to 36 mol. %,
• said third component is ethane or ethylene in an amount of 28 mol. % to 35 mol. %, and
• said fourth component is n-butane or isobutane in an amount of 22 mol. % to 28 mol. %, or n-pentane or isopentane in an amount of 15 mol. % to 25 mol. %;
• or
• (b) said first component is nitrogen in an amount of 15 mol. % to 25 mol. %,
• said second component is methane in an amount of 28 mol. % to 35 mol. %,
• said third component is ethane or ethylene in an amount of 23 mol. % to 36 mol. %, and
• said fourth component is isobutane in an amount of 21 mol. % to 28 mol. %, isopentane in
• an amount of 15 mol. % to 22 mol. %, or propane in an amount of 30 mol. % to 40 mol. %;
• or
• (c) said first component is nitrogen in an amount of 10 mol. % to 35 mol. %,
• said second component is methane in an amount of 20 mol. % to 40 mol. %,
• said third component is ethane in an amount of 5 mol. % to 35 mol. %, and
• said fourth component is 1-butene in an amount of 10 mol. % to 35 mol. %;
• or
• (d) said first component is nitrogen in an amount of 18 mol. % to 25 mol. %,
• said second component is methane in an amount of 28 mol. % to 34 mol. %,
• said third component is ethane in an amount of 20 mol. % to 27 mol. %, and
• said fourth component is 1-butene in an amount of 20 mol. % to 28 mol. %, or propane in an amount of 30 mol. % to 40 mol. %.