Modular pressure swing adsorption apparatus

A rotary module for implementing a pressure swing adsorption process having an operating pressure cycling between an upper pressure and a lower pressure for extracting a first gas fraction and a second gas fraction from a gas mixture including the first and second fractions, the rotary module comprising:

• a stator including a first stator valve surface, a second stator valve surface, a plurality of first function compartments opening into the first stator valve surface, and a plurality of second function compartments opening into the second stator valve surface;
• and
• a rotor rotatably coupled to the stator and including a first rotor valve surface in communication with the first stator valve surface, a second rotor valve surface in communication with the second stator valve surface, a plurality of flow paths for receiving adsorbent material therein, each said flow path including a pair of opposite ends, and a plurality of apertures provided in the rotor valve surfaces and in communication with the flow path ends and the function compartments for cyclically exposing each said flow path to a plurality of discrete pressure levels between the upper and lower pressures to provide substantially uniform gas flow through the first and second function compartments;
• wherein the first function compartments include a plurality of countercurrent blowdown compartments for subjecting the flow paths to a plurality of incremental pressure drops, and a heavy reflux return compartment communicating with at least one of the countercurrent blowdown compartments, and the stator includes a reflux compressor coupled between the countercurrent blowdown compartments and the heavy reflux return compartment for delivery gas removed from the countercurrent blowdown compartments at increased pressure to the heavy reflux return compartments.

A rotor for implementing a pressure swing adsorption process, the rotor comprising:

• an annular body including an inner valve surface and an outer valve surface;
• a plurality of flow paths provided within the body and extending between the inner valve surface and the outer valve surface;
• and
• a plurality of apertures provided in the valve surfaces in communication with the flow paths for allowing a gas flow through the flow paths, at least one of the valve surfaces being configured for maintaining the gas flow substantially uniform.

A pressure swing adsorption system for extracting a first gas fraction and a second gas fraction from a gas mixture including the first and second fractions, the pressure swing adsorption system comprising:

• a rotary module coupled to a gas feed manifold, a heavy product manifold, and a light product manifold, the rotary module comprising:
• a stator including a first stator valve surface, a second stator valve surface, a plurality of first function compartments opening into the first stator valve surface, and a plurality of second function compartments opening into the second stator valve surface;
• and
• a rotor rotatably coupled to the stator and including a first rotor valve surface in communication with the first stator valve surface, a second rotor valve surface in communication with the second stator valve surface, a plurality of flow paths for receiving adsorbent material therein, each said flow path including a pair of opposite ends, and a plurality of apertures provided in the rotor valve surfaces and in communication with the flow path ends and the function ports;
• compression expansion machinery coupled to the rotary module for maintaining the function ports at a plurality of discrete pressure levels between an upper pressure and a lower pressure for providing substantially uniform gas flow through the flow paths;
• wherein the function compartments include a plurality of gas feed compartments, and the compression/expansion machinery comprises a multi-stage compressor including a plurality of pressure output ports, each said pressure output port being coupled to a respective one of the feed compartments for delivering feed gas to the flow paths at a plurality of pressure increments;
• and
• wherein the multi-stage compressor comprises a multi-stage axial flow split stream compressor including a plurality of annular stator rings of progressively decreasing diameter, each said stator ring including an annular flow area and a plurality of stator blades, and a rotor having an axis or rotation and including a plurality of rotor blades cooperating with the stator blades for compressing gas flow through the flow area, at least one of the said stator rings further including a collector and a diffuser for apportioning the compressed gas flow between the collector and the flow area of a subsequent one of the stator rings.