Regenerative Pumps

FIG. 10-47 Characteristic curves of a regenerative pump. To convert gallons per minute to cubic meters per hour, multiply by 0.2271 to convert feet to meters, multiply by 0.3048 and to convert horsepower to kilowatts, multiply by 0.746. 

Impeller wheels for regenerative pumps, pump rotors, laundry system wheels, submersible pump insulation, dry transformer insulation. .. 

To meet the supercritical conditions more suitable a mixer-settler unit has been developed by Schaffner [2], A regenerative pump was used as mixer to achieve an intense contact between the two phases and to create a large mass transfer surface area. This type of pump is capable of conveying gases as well as liquids and creates a high pressure difference which is used to separate the phases in the following fluid cyclone (fig. 1). 

Figure 2. Simplified schematic drawing of the extraction plant (1 regenerative pump, 2 fluid cyclone, 3 storage tank, 4 gear pump, 5 circulation gas condensator, 6 diaphragm pump, 7 heat recovery, 8 preheater, 9 heat exchanger, 10 cyclone separator, 11 feed pump, 12 feed preheater, 13 thermostatic chamber)...

The regenerative pumps (1) consist of two double-suction impellers, each with a diameter of 0.036 m in series to increase the total pump head. All pumps are equipped with speed control and differential pressure sensors. The mixed phases enter the fluid cyclone (2) of 0.020 m diameter with a tangential tube entry. The underflow of the cyclones is connected to a small storage tank (3) with level con-... 

Measurements for the singe stage module [2] showed that the regenerative pump is able to create a mass transfer surface area between 2000 and 3500 m2/ m3 at liquid phase ratios of about 5 %. The drop size distribution was determined and varied between 30 and 200 pm. The measurements were taken at the outlet of the regenerative pump with a photo camera. The calculated surface area was very high compared to conventional packing as shown in table 3. 

The specific surface area created by the regenerative pump was 3-7 times higher than that in a packed column. In addition to this, it should be noted that the column packing very often is not completely wetted. 

EFFECT OF LIQUID VISCOSITY ON REGENERATIVE PUMP PERFORMANCE 6.57... 

FIGURE 6.34 Regenerative pump performance when handling water and oil. (Aurora Pump Division, The New York Air Brake Co.)... 

Evaluate the effect of viscosity on pump performance. Study Fig. 6.34 to determine the effect of increased liquid viscosity on the performance of the pump. Thus at a given head—say 100 ft—the capacity of the pump decreases as the liquid viscosity increases. At 100-ft head, this pump has a water capacity of 43.5 gal/min (Fig. 6.34). The pump capacity for the various oils at 100-ft head is 36 gal/min for 400 SSU, 32 gal/min for 600 SSU, 28 gal/min for 900 SSU, and 26 gal/min for 1000 SSU, respectively. There is a similar reduction in capacity of the pump at the other heads plotted in Fig. 6.34. Thus, as a general rule, it can be stated that the capacity of a regenerative pump decreases with an increase in liquid viscosity at constant head. Or conversely, at constant capacity, the head developed decreases as the liquid viscosity increases. 

Turbine or regenerative pumps, which resemble centrifugal pumps but because of a quite different impeller design can produce much larger pressure rises than centrifugal pumps of the same size and speed... 

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