Pressure swing adsorption for concentration of a gas component

Apparatus for concentrating a first component from a feed gas mixture containing the first component and a second component, and separating the feed gas mixture into a product gas enriched in the first component and a depleted gas mixture enriched in the second component and depleted in the first component;

• one of the first and second components being more readily adsorbed under increase of pressure relative to the other component which is less readily adsorbed under increase of pressure over an adsorbent material, such that a mixture of the first and second components contacting the adsorbent material is relatively depleted in the first component at a first pressure and is relatively enriched in the first component at a second pressure when the pressure is cycled between the first pressure and the second pressure at a cyclic frequency;
• and the apparatus including:
• (a) an adsorbent bed of the adsorbent material within a working space, the adsorbent bed having a flow path through the adsorbent material, and the flow path contacting the adsorbent material between first and second ends of the flow path,
• (b) feed supply means for introducing the feed gas mixture to adjacent the first end of the flow path,
• (c) product delivery means for withdrawing the product gas from adjacent the second end of the flow path,
• (d) exhaust means for exhausting the depleted gas mixture from the apparatus,
• (e) a second space within the working space communicating with the second end of the flow path,
• (f) cyclic volume displacement means for cyclically changing the volume of the working space at the cyclic frequency, so as to change the working pressure in the flow path cyclically between the first pressure and the second pressure,
• (g) means to generate flow in the flow path in a first direction from the first end to the second end of the flow path, when the working pressure is substantially the second pressure, so that gas enriched in the first component will flow out of the adsorbent bed from the second end of the flow path,
• (h) means to generate flow in the flow path in a second direction reverse to the first direction, when the working pressure is substantially the first pressure, so that depleted gas mixture will flow out of the adsorbent bed from the first end of the flow path,
• (i) means to change the volume of the second space at the cyclic frequency, so that the volume of the second space is expanding when the pressure is substantially the second pressure, and the volume of the second space is contracting when the pressure is substantially the first pressure,
• (j) means to exchange depleted gas mixture for feed gas mixture, so as to restrict reintroduction of the depleted gas mixture to the flow path,
• (k) means to restrict mixing of depleted gas mixture about to be exhausted with feed gas mixture that will be introduced to the flow path.

Apparatus for separating a more readily adsorbed component and a less readily adsorbed component from a gas mixture;

• the apparatus including a first cyclic volume displacement means communicating with first and second adsorbent beds and also communicating with feed supply means to introduce the gas mixture to the adsorbent beds adjacent the first cyclic volume displacement means;
• with a flow path through the first adsorbent bed connecting the first cyclic volume displacement means to a second cyclic volume displacement means, and a flow path through the second adsorbent bed connecting the first cyclic volume displacement means to a third cyclic volume displacement means;
• the apparatus having product delivery valve means connected to each of the second and third cyclic volume displacement means;
• and the apparatus having drive means so that the three cyclic volume displacement means cycle at the same frequency and with relative phase so that the flow through the adsorbent beds is directed toward the second cyclic volume displacement means when the pressure is relatively elevated, and the flow through the adsorbent beds is directed toward the third cyclic volume displacement means when the pressure is relatively lowered;
• so that gas enriched in the first component is withdrawn form the product delivery valve adjacent the second cyclic volume displacement means, while gas enriched in the second component is withdrawn from the product delivery valve adjacent the third cyclic volume displacement means.

Apparatus for separating a product gas substantially purified in a first component from a feed gas mixture containing the first component and a second component;

• one of the first and second components being more readily adsorbed under increase of pressure relative to the other component which is less readily adsorbed under increase of pressure over an adasorbent material under the working conditions of the apparatus;
• the apparatus enclosing a working space including a flow path through an adsorbent bed of the adsorbent material, and the working space including a second space communicating with one end of the flow path;
• the apparatus including cyclic volume displacement means to change the total volume of the working space and thus to change the working pressure within the working space at a cyclic frequency, and also to change the volume of the second space at the same frequency;
• the apparatus further including means to generate flow in the flow path with the direction of flow reversing at the cyclic frequency and with a phase relation to the changes of working pressure, so as to provide in one part of the cycle flow enriched in the first component directed into the second space from the adsorbent bed during part of the cycle, and in a subsequent part of the cycle flow in the opposite direction from the second space back into the flow path in order to purge the adsorbent bed of gas enriched in the second component;
• the apparatus further characterized by:
• (a) flow distribution means cooperating with the adsorbent bed and the second space to maintain within the second space substantial uniformity of the instantaneous flow velocity relative to the adsorbent bed in the transverse dimension to the flow direction, so as to establish substantial stratification of gas in the second space according to the time of entry from the adsorbent bed, in order to improve the effectiveness of the purge step and thus improve the purity of the product.

Apparatus for separating first and second components of a gas mixture, one of the first and second components being more readily adsorbed under increase of pressure relative to the other component which is less readily adsorbed under increase of pressure over an adsorbent material under the operating conditions of the apparatus;

• the apparatus including an adsorbent bed of the adsorbent material with a flow path through the adsorbent bed;
• the apparatus further including means to introduce the gas mixture to the flow path, means to generate cyclic flow in the flow path with the direction of flow reversing at a cyclic frequency, and means to generate cyclic pressure variations of the gas in the flow path at the cyclic frequency and with phase coordinated so that the pressure is relatively increased when the gas is flowing in a first direction in the flow path through the adsorbent bed, and the pressure is relatively decreased when the gas is flowing in the reverse direction in the flow path;
• the apparatus further characterized as follows:
• (a) the flow path comprises a plurality of narrow and substantially identical parallel passages, said passages being provided as gaps defined by spacer means between adjacent layers of a spirally wound ribbon of sheet material on which the adsorbent material is supported.

Apparatus for separating a gas mixture including a first component and a second component, one of the first and second components being more readily adsorbed under increase of pressure relative to the other component which is less readily adsorbed under increase of pressure over an adsorbent material under the working conditions of the apparatus;

• the apparatus including first and second working spaces respectively enclosing first and second adsorbent beds of the adsorbent material, means to generate cyclically reversing flow at a cyclic frequency in a flow path through each adsorbent bed, first and second cyclic volume displacement means respectively communicating with the first and second working spaces so as to change the volumes thereof, and drive means cooperating with the first and second cyclic volume displacement means and the means to generate cyclically reversing flow in the flow paths so that the cyclic volume displacement means are cyclically actuated in opposite phase;
• the drive means further characterized by:
• (a) means to exchange energy between the first and second cyclic volume displacement means, so that work of compression to reduce the volume of one working space is in part provided by the work of expansion to increase the volume of the other working space,
• (b) means to change the volume of each working space relatively rapidly when the pressure difference between the working pressure in that working space and the external pressure contacting the drive means is relatively small, and to change the volume of each working space relatively slowly when the pressure difference between the working pressure and the external pressure is relatively large, so as to reduce peak power demand of the drive means by approximately balancing power between the first and second cyclic volume displacement means.