Vertical condensate pump

The vertical condensate pumps are located just to the south of the condenser and should straddle the centerline of the hot well outlet nozzle. The distance between the condenser and the pumps is dictated by pump operation and maintenance requirements as well as piping flexibility. 

Vertical condenser (when required to liquefy the fluid prior to recycling by pumping) with one pass on the tube side and downward flow of process fluid so as to avoid plugging by extract entrained from the separators... 

Two 50% capacity condensate pumps operate in parallel during normal operation. A third 50% capacity condensate pump is provided and maintained in standby for automatic starting if required. Each pump is electric -motor driven, vertical and installed at an elevation that allows operation at low condensate level in the main condenser hotwell. 

Condensate pump The condensate pump (Exhibit 4-7), which is usually vertical, removes the condensate from the hot well in the surface condenser. Condensate forms during liquefaction in the condenser and is coUeaed in the hot well. 

An additional problem with condensate temperature control, via cooling-water manipulation, relates to column safety. In an instance with which one of the authors is painfully familiar, an atmospheric column with such a control system was running at a very low feed rate. Condensate temperature became too low, so the controller closed the cooling-water valve located in the exit line from a vertical condenser. The water in the shell b an to boil, the valve could not pass the required volume of steam, the cooling-water pump stalled, and product vapor issued in great quantities fix>m the vent. Fortunately, an alert operator shut the column down before any damage occurred. 

A common form of turbine pump is the vertical pump, which has the pump element mounted at the bottom of a column that serves as the discharge pipe (see Fig. 10-46). Such units are immersed in the liquid to be pumped and are commonly used for wells, condenser circulating water, large-volume drainage, etc. Another form of the pump has a shell surrounding the pumping element which is connected to the intake pipe. In this form, the pump is used on condensate service in power plants and for process work in oil refineries. 

An innovation is a direct-contact condenser mounted on the vapor body. A short piece of vertical pipe connects the vapor body with the condenser to minimize piping and pressure drop. This design also eliminates structural steel for support of a separate condenser. For cooling tower applications, the hotwell is elevated to permit gravity flow of water from the hotwell to the top of the cooling tower, thus eliminating the need for a pump. 

Figure 6,1-2 is a simplified illustration of a BWR. The pressure of the moderator-cooling water at about half the pressure in a PWR forms steam as it flows upward through the core. Steam passes through a moisture separator (shown as vertical lines just above the core) exits the containment through Main Steam Isolation Valves (MSIV) drives the turbine and generates electricity. After the steam is cooled by the turbine, it is condensed, and pumped back to the reactor by the feedwater pump. 

The so-called hydro-vac pump, shown in Fig. II, 22, 2 (the upper half of the mercury reservoir and the column above it are insulated by a layer of asbestos), is an inexpensive, all-glass, mercury diffusion pump, which can be used in series either with an oil piunp or with a water filter pump (compare Fig. II, 21,1) capable of producing a vacuum of at least 2 mm. It is accordingly of particular value in the organic laboratory for vacuum distillations, fractionations, sublimations and pyrolyses as well as for molecular distillations (see Section 11,26). The hydro-vac pump, unlilce an oil pump, may be used in operations which evolve moisture and non-condensable or corrosive vapoius. In use the piunp is clamped in a vertical... 

The water is then conveniently discharged at atmospheric pressure, without the aid of a pump, by allowing it to flow down a vertical pipe, known as a barometric leg, of sufficient length for the pressure at the bottom to be slightly in excess of atmospheric pressure. For a jet condenser with a barometric leg, a chart for determining the water requirement has been prepared by Arrowsmith(49), and this is shown in Figure 14.27. 

Condensation Outside Vertical Tubes. This arrangement requires careful distribution of coolant to each tube, and requires a sump and a pump for return to a cooling tower or other source of coolant. Advantages are the high coolant side heat transfer... 

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