Feed pumps pump curves

Variable-Pressure, Variable-Rate Filtration The pattern of this categoiy comphcates the use of the basic rate equation. The method of Tiller and Crump (loc. cit.) can be used to integrate the equation when the characteristic curve of the feed pump is available. 

The power-generating potential of a water-dominated resource depends on the geothermal fluid temperature and production flow rate (Fig. 2). The figure gives the net power output, which accounts for parasitic loads caused by the condenser and feed pump power requirements. The output power from two-phase water-steam or steam alone is much greater than the curves shown for liquid in Fig. 2. 

The feed pump is a centrifugal with a characteristic curve represented by the equation... 

Related Calculations. Use this procedure for any condensate or boiler-feed pump handling water at an elevated temperature. Consult the Standards of the Hydraulic Institute for capacity curves of... 

Figures 10 and 11 show transient conversion data for MMA experiments. As one can easily see, the shapes of these curves are quite different. The major difference in the experiments was the start-up procedure. The data in Figure 10 resulted when the reactor was started empty. In this run the feed stream pumps were started at t = 0 and the reactor overflow first occurred at t = 0. As one can readily see, the conver-. sion oscillates widely in an apparently undamped fashion.

The start-up procedure for the experiments shown in Figure 11 involved filling the reactor with distilled, deionized water prior to starting the feed stream pumps. In these runs the conversion seems much more stable. The top curve, however, demonstrates that these apparently stable steady states may be subject to rapid change perhaps the seeking of a new, more stable, steady state or the beginning of oscillations. ... 

Downstream restriction. At the maximum obtainable flow, check the feed of head (as described previously) on the pump curve. If the pump is putting up the head indicated on the curve, do not pull the pump. Ask the instrument mechanic to check the control valve on the discharge line. Perhaps it is not opening all the way or the downstream pressure requirement has increased due to a lunch bucket lodged in an exchanger inlet. 

Reverse osmosis feed pumps are sized using the required flow rate and operating pressure. Pump curves, as shown in Figure 6.4, are then consulted to determine the number of stages, impeller diameter, and horsepower (hp). 

In case of pumped feed, the feed rate may decrease because of increased column pressure. If possible and if the pump curve is available, the reduced feed rate can be estimated. In most cases, this involves complex calculation, which can be avoided with a little sacrifice of accuracy. 

Figure 15.4 A plant for the production of animal feed. The heat pump encroaches into a pocket in the gremd composite curve. (From Smith and Linnhojf, Trans. IChemE, ChERD, 66 195, 1988 reproduced by permission of the Institution of Chemical Engineers.)...

The reactor in Fig. 5 operates as follows. A feed solution containing a given concentration of pollutant is pumped to the adsorbent module at a fixed volumetric flow rate. The module is kept isothermal by a temperature control unit, such as a surrounding water bath. Finally, the concentration of the outlet solution is measured as a function of time from when the feed was introduced to the adsorbent module. These measurements are often plotted as breakthrough curves. Example breakthrough curves for an aqueous acetone solution flowing... 

Assume that a boiler feed water is being pumped at 180 °F. Read the chart in Figure 3-46 and the water vapor pressure curve, and follow over to read NPSH reduction = 0.45 feet. A pump selected for the sertice requires 6 feet cold water service NPSHr ... 

Using the example of Reference [6], assume a pump with characteristic curve and added temperature rise data as showm on Figure 3-59 is to handle boiler feed water at 220°F, with a system available NPSH = 18.8 feet. The v apor pressure of w ater at 220°F is 17.19 psia from steam tables and the SpGr = 0.957. Correcting the 18.8 feet NPSHa psia = 18.8 (l/[2.31/0.957)] = 7.79 psia at 220°F. 

The volume of reactor without beads was 1.4 1. The column was loaded with the solidified uniform beads of S. cerevisiae. The void volume of the reactor was 660 ml when it was packed with immobilised beads. The growth of beads with different proportions of column packing is shown in Figure 8.9. A fresh feed of 10 g l 1 glucose solution was pumped from the bottom of the reactor. The optimum amount of packing obtained was 65-70% of the reactor volume. The trend of the collected data resembles the growth curve of yeast in... 

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