Condensate drainage

Provide horizontal cut 1.75 in. deep on a Hower baffles to allow for condensate drainage. Remove the 9 tubes in this cut area to allow free drainage, see Figures 11-52A and B. 

Condensate drainage devices, 70 148 Condensate polishing ion exchange in, 74 417 in steam-generating systems, 23 227 water softening method for, 26 122-123 Condensate return, in heat pipes, 73 226 Condensate return systems, 70 147-148 Condensate systems, in industrial water treatment, 26 136-137 Condensation, 9 281-282. See also Polycondensation control of VOCs by, 26 679-680 ketone, 74 570... 

The reason is condensate backup. The condensate backup causes subcooling that is, the liquid is cooled below its bubble point, or saturated liquid temperature. Perhaps a rat has lodged in the condensate outlet pipe. The rat restricts condensate drainage from the shell side. To force its way past the dead rat, the propane backs up in the condenser. The cold tubes in the bottom of the shell are submerged in liquid propane. The liquid propane is cooled below its bubble-point temperature. 

Finally, the condenser drainage tube is joined on and annealing should follow the procedure described in Chapter 6, p. 120. The drainage tube is cut off at about 45 to the centre line and fire-polished. 

I. D. R. Grant and B. D. J. Osment, The Effect of Condensate Drainage on Condenser Performance, National Engineering Laboratory Report No. 350, East Kilbride, Glasgow, 1968. 

Flow maldistribution problems in condensers may be severe and should not be underestimated [146], Most problems with flow maldistribution in condensers, though, can be resolved through good venting and condensate drainage [2],... 

Steam headers should drain to the steam separator for more effective condensate collection. Branch connections to steam headers usually connect to the top to avoid excessive condensate drainage to equipment. 

Automatic condensate drainage from gas lines shall be provided. 

Remove harmful chemical sources when they exceed recognized limits Remove dirty air filters in HVAC systems Empty all condensate drainage trays... 

Air-cooled condensers are normally sloped toward the outlet to provide for better condensate drainage in the tubes. It is extremely important that air-cooled condensers be installed so that the outlet of the tubes in a pass is at least at the same elevation as the inlet to avoid condensate flooding preferably it should be a few inches lower. This is even more important when the freezing point of the condensate is higher than the lowest possible air temperature. Multipass condensers may be sloped in more than one direction at a fairly nominal cost. In some instances, the condensate outlet header is provided with a sump" by making the outlet header deeper. This prevents the bottom row of tubes from being flooded by condensate and avoids problems associated with Improper venting. 

Butrymowicz, D., Trela, M. and Karwacki, J. (2003). Enhancement of condensation heat transfer by means of passive and active condensate drainage techniques. International Journal of Refrigeration, Vol. 26, pp. 473 84. 

The reactor installation has two heat removal channels each is able to remove up to 3% of the nominal reactor power. Each channel consists of a cooling condenser connected with a separator and cooled by water, and a condensate drainage pipeline with a direct-acting control valve, which opens if the pressure in the separator exceeds the nominal value. 

FIGURE 18-11 Variable-channel head pressure promotes uneven condensate drainage. 

As shown in Figure 13-6, ihe seal legs function to drain oil and water from the shell side of the condenser. The inability to maintain condenser drainage will severely reduce ejector efficiency by backing liquid up in the condenser shell. With experience, one can find the liquid level inside the condenser shell by feeling for the temperature gradient by hand. Condenser tubes submerged in liquid are effectively out of service. 

FIGURE 18-10 Steam reboiler condensate drainage system is improperly designed. 

The steam trap neither aids nor retards condensate drainage, unless it is mechanically malfunctioning, meaning it is sticking either open or closed. Also, replacing the steam trap with a condensate drum and LRC also neither retards nor aids drainage. Condensate drainage is a function of system hydraulics, as discussed in subsequent sections. 

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