Pressure swing parametric pumping

The term parametric pumping was coined by Wilhelm et al. [Wilhelm, Rice, and Bendelius, Ind. Eng. Chem. Fundam., 5,141-144 (1966)] to describe a liquid-phase adsorption process in which separation is achieved by periodically reversing not only flow but also an intensive thermodynamic property such as temperature, which influences adsorptivity. Moreover, they considered the concurrent cycling of pressure, pH, and electrical and magnetic fields. A lot of research and development has been conducted on thermal, pressure, and pH driven cycles, but to date only gas-phase pressure-swing parametric pumping has found much commercial acceptance. 

This section outlines the basic pressure-swing parametric pumping process, which will be described below in the context of oxygen production from air. The preferred adsorbent for this separation can be either 5A or 13X zeolite. 

The key feature of pressure-swing parametric pumping is the unusual pressure versus distance and time feature of the bed. 

In PSA, pressure drop is purposely minimized, so that, although the pressure within a bed changes substantially during a cycle, the pressures at various points in a bed at a given time are virtually the same. In pressure-swing parametric pumping, large... 

Figure 3. Schematic of pressure-swing parametric pump...

Pressure-swing parametric pumping would seem to have many applications for separation of from very small to quite large gas streams. One area of promise is the production of oxygen from air. Union Carbide is currently marketing a small device for producing up to about six liters per minute of 90+ percent oxygen for medical use in homes. This device actually contains... 

COMPARISON OF PRESSURE-SWING ADSORPTION AND PRESSURE-SWING PARAMETRIC PUMPING FOR PRODUCTION OF OXYGEN FROM AIR... 

The adsorbent particles in pressure-swing parametric pumping are substantially smaller than those in PSA and produce rapidly fluctuating pressure profiles in the bed during a cycle. These profiles and the cycle times which influence them are responsible for the continuous product flow, the high productivities and the high product purities which can be attained in the process. 

The second process, called pressure-swing parametric pumping (PSPP), was developed to minimize process complexity... 

COMPARISON OF THE PERFORMANCES OF POLYBED PSA AND PRESSURE-SWING PARAMETRIC PUMPING WITH BASIC PSA... 

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