Pressure swing adsorption process

• US 4,234,322 A
• Filed: 05/23/1979
• Issued: 11/18/1980
• Est. Priority Date: 05/27/1978
• Status: Expired due to Term

• Current Assignee: Linde AG (Linde Plc)
• Original Assignee: Bayer AG
• Inventors: De Meyer, Herman, Doclo, Roland, Seynaeve, Jan
• Primary Examiner(s): Spitzer, Robert H.
• Application Number:
  US06/041,662
• Time in Patent Office: 545 Days
• Field of Search: 55/18, 55/21, 55/25, 55/26, 55/58, 55/62, 55/74, 55/75
• US Class Current: 95/19
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2257/102 Nitrogen
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2259/40007 Controlling pressure or temperature swing adsorption
• CPC Class Codes: B01D 2259/4003 with two sub-steps
• CPC Class Codes: B01D 2259/40041 with more than three sub-steps
• CPC Class Codes: B01D 2259/40052 Recycled product or process gas
• CPC Class Codes: B01D 2259/40075 More than ten
• CPC Class Codes: B01D 2259/40081 Counter-current
• CPC Class Codes: B01D 2259/4065 using eight beds
• CPC Class Codes: B01D 53/047 Pressure swing adsorption
• CPC Class Codes: C01B 2203/043 Regenerative adsorption process in two or more beds, one for adsorption, the other for regeneration
• CPC Class Codes: C01B 2203/0465 Composition of the impurity
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 3/56 by contacting with solids; Regeneration of used solids C01B3/508 takes precedence
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/151 Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

An adiabatic pressure swing adsorption process for the separation of gas mixtures by adsorbing at least one gas component in each of at least eight phase staggered operated adsorbent beds, which can be continued to be operated without any stoppage of installation even if one adsorbent bed is removed from operation due to a defective valve.

Claims

1. In an adiabatic pressure swing adsorption process for separation of gas mixtures by adsorbing at least one gas component in each of at least eight phase staggered operated adsorbent beds;

wherein each of the adsorbent beds is cyclically operated in subsequent operation steps including adsorption, at least two depressurization steps, countercurrent purging, and at least two;

repressurization steps;

depressurization and repressurization being established by pressure equalization with another adsorbent bed being operated in the operation step repressurization depressurization respectively of adjacent pressure range by means of a number of connecting tubes and valves opening from said adsorbent beds to said connecting tubes;

the valves being switched according to a predetermined first valve operation pattern;

switching of valves being initiated when a first characteristic physical quantity has reached a predetermined value;

the improvement comprising periodically compairing measured actual values with predetermined corresponding nominal values of a second physical quantity characteristic for each operation step;

in the case of deviations of the actual values from the nominal values, identifying any valve being potentially defective and therefore potentially responsible for said deviations in any of subsequent operation steps after the first occurence of deviation;

identifying the actual defective valve as being the sole valve being identified as potentially defective in any of a sufficient number of operation steps to exclude other valves being also identified as potentially defective in said operation step of first occurance of a deviation;

excluding the adsorption bed to which the defective valve belongs from operation by continuing operation of the remaining adsorption beds according to a second valve operation pattern predefined for a such reduced number of adsorption beds.

2. The process according to claim 1 wherein the first physical quantity is a predetermined time interval and the second physical quantity is pressure, the actual values thereof are measured in at least one of the adsorbent beds and the connecting tubes, the nominal values thereof being predetermined according to the valve characteristics.

3. The process according to claim 1 wherein the first physical quantity is pressure, switching being initiated when the predetermined value is reached in any of the adsorbent beds and connecting tubes, and the second physical quantity is time, the actual values thereof being the time interval until a particular switch-initiating pressure is reached, the nominal values thereof being predetermined according to the valve characteristics.

4. The process according to claim 3 wherein the first physical quantity is the pressure in the repressurized adsorbent bed.

5. The process according to claim 1 wherein the first physical quantity is a predetermined time interval, during which a predetermined pressure in at least one of the adsorbent beds and connecting tubes is realized by valve operation control, and the second physical quantity is the valve setting, the nominal values of the valve setting being predetermined according to the valve characteristics.

6. The process according to one of claims 1 to 5 wherein if during operation according to the second valve operation pattern a defective valve is identified the adsorbent bed to which the defective valve belongs is excluded from operation by continuing operation of the remaining adsorbent beds according to a third valve operation pattern predefined for a such reduced number of adsorbent beds.