Multi-stage gas compression system

An apparatus, comprising:

• a hydraulic actuator comprising:
• a hydraulic cylinder extending about a central axis;
• and
• a hydraulic piston configured for reciprocating movement within and in sealing engagement with the hydraulic cylinder along the central axis responsive to an application of pressurized hydraulic fluid against opposing sides of the hydraulic piston;
• a central shaft having a medial portion and opposing first and second ends, the central shaft aligned with the central axis, the hydraulic piston affixed to the medial portion of the central shaft;
• a first compression stage affixed to a first end of the hydraulic cylinder and comprising:
• a first compression cylinder extending about the central axis and having a first sidewall thickness;
• and
• a first compression piston configured for reciprocating movement within and in sealing engagement with the first compression cylinder responsive to the reciprocating movement of the hydraulic piston, the first compression piston having a first overall diameter;
• a second compression stage affixed to an opposing second end of the hydraulic cylinder and comprising:
• a second compression cylinder extending about the central axis and having a second sidewall thickness greater than the first sidewall thickness;
• and
• a second compression piston configured for reciprocating movement within and in sealing engagement with the second compression cylinder responsive to the reciprocating movement of the hydraulic piston, the second compression piston having a second overall diameter less than the first overall diameter, wherein the hydraulic actuator, the first compression stage and the second compression stage form an cylindrical compression stack of a multi-stage compressor assembly, the cylindrical compression stack having a nominally constant outermost diameter along an overall length thereof;
• and
• a conduit assembly comprising:
• a first conduit section connected to an inlet port of the first compression cylinder to facilitate a first flow of a gas at a first pressure into an interior of the first compression cylinder;
• a second conduit section connected between an outlet port of the first compression cylinder and an inlet port of the second compression cylinder to facilitate a second flow of the gas at a second pressure higher than the first pressure from the interior of the first compression cylinder to an interior of the second compression cylinder responsive to advancement of the hydraulic piston in a first direction along the central axis to compress the gas within the first compression cylinder;
• and
• a third conduit section connected to an outlet port of the second compression cylinder to facilitate a third flow of the gas at a third pressure higher than the second pressure responsive to advancement of the hydraulic piston in an opposing second direction along the central axis to compress the gas within the second cylinder, wherein a difference between the third pressure and the second pressure is determined in relation to a difference between the first sidewall thickness and the second sidewall thickness.