Condensers startup venting

Device used to vent non-condensable gases from a boiler during startup and shutdown procedures. 

When the plant is located in built-up areas, there might also be an atmospheric condenser that receives the steam, which is vented during the startup to decrease the noise level at the plant. The auxiliary circuits of the steam turbine are the lube oil, control fluid, and vacuum system for the condenser. 

Horizontal shell-and-tube condenser with liquid coolant in the tubes and vapor on the shell side (Figure 3.1). This is probably the most popular type in petroleum refineries. By comparison with the vertical design discussed below, it is much better suited to partially flooded operation. In addition, at startup time, column inerts are usually vented more easily (i.e., with less pressure drop) through condensers of this design. 

With a longer condensing path, it is also better suited to applications in which it is desired to absorb the maximum amount of low boilers in the condensate. This condenser commonly has at its lower end a vapor-liquid disengaging pot, which also serves as a condensate receiver. Because all vapors must pass through the tubes, the speed of venting inerts at startup time is limited. For the same reason, this type of condenser cannot be operated partially flooded. ... 

---