Process Condensers- orientation

[MJCronin]

One of our clients has posed a question to us about replacement of some leaking process condensers. The condensers service part of a distillation process. The existing units are of shell & tube design, horizontal axis -(TEMA AJM) with the process vapors on the shell side and cooling water-tubeside.

The client has been asking about possible replacement of these units with vertical axis condensers having process vapors on the tubeside.

My question is this:

By what criteria does the process designer choose between a horizontal and vertical HX design ? Are there any texts or reference books that discuss this ? Any websites with this discussion ?

Thank You all in advance.....


MJC

 

[MortenA]

Just a input in another direction: Why not a spiral HX. They should be great for condensing service. Alfa Laval makes them.

Best Regards

Morten

 

[BillBirch]

I would say that space would be the basic criterion for selecting a horizontal or vertical orientation. If the bundles are not too long (requiring substantial support), it may be economical to support off the column. As the process flow will be from the column, savings in piping can be achieved.
Next comes the choice between tube and shell side fluids. Does your process vapour have a tendency to foul, corrode or exist at a high pressure. In any of these cases, the process vapour should be considered in the tube side, provided sufficient residence time is available for condensing to occur (sufficient tube length).
The vertical configuration lends itself to thermosyphon action in the cooling water (which is where your client may be coming from). As the cooling water is heating through the exchanger, pumps are assisted by the buoyancy of the warm water rising.
The degree of maintenance anticipated may be your deciding factor, if exchangers are expected to be cleaned regularly, it would be easier to clean horizontal exchangers on the ground, rather than vertical exchangers in the air.
Finally, I assume that you will be pumping the condensed process fluid - what about NPSHA? Will the available head of a vertical exchanger improve this?
Frankly, in my opinion, you client may have a good idea, if tested against the above criteria.
Regards,
Bill Birch
Seasons Greetings to all

 

[BillBirch]

Further to the above, the vertical configuration would only be useful for a single tube pass configuration.

Regards,
Bill Birch