Primary-jet discharge pressure

The pressure in condenser A is greater than that in the surface condenser, and less than that in the final condenser (condenser B). This means that condenser A is operating at vacuum conditions. This prevents the condensed steam formed in condenser A from draining out to atmospheric pressure, unless the condenser is elevated by 10 to 15 ft. To avoid this problem, the condensate is drained back to the lower-pressure surface condenser. To prevent blowing the noncondensable vapors back to the surface condenser as well, a loop seal is required. The height of this loop seal must be greater than the difference in pressure (expressed in ft of water) between the surface condenser and the primary jet discharge condenser (condenser A). 

Let s refer to Fig. 16.2. As the cooling water warms, the temperature of condenser 1 increases. This also increases the condensing pressure. This raises the discharge pressure of the primary jet (jet 1), as well as the pressure in the diffuser throat (see Fig. 16.1). Higher pressure will result in a smaller vapor volume. And a smaller vapor volume will cause a reduction of the velocity in the diffuser throat. 

Although some early research did focus on introducing a pulsed external ion beam from a plasma jet into the acceleration region of the TOF-MS [12], it has not been until recently that continuous ion sources such as plasmas, electrospray devices, and other atmospheric-pressure discharges have been coupled with TOF-MS. Unfortunately, the inherently pulsed nature of the spectrometer can cause this marriage to be quite inefficient. The primary challenge in using the TOF-MS with... 

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