Alfa Laval HX

[cammax]

I was wondering if anyone has had issues with Alfa Laval plate and frame HX when used with open cooling towers?
model used: M15-BFG

I seem to have lost capacity (flow) in a very short period of time, 6 months, and when looking into this I found the flow passages are very small, seems like a poor fit for this application.

 

[pmover]

yes, as you have now & correctly observed, plate frame exchangers are not suitable for fluids prone to fouling (i.e. cooling tower water; moreso if an open system). due to the small passages, the fluid must be clean at all times.

good luck!
-pmover

 

[Yorkman]

That's the trade off for a great approach, I've seen misinformed operators shut down the bleed system on the cooling tower because it wasted too much water!! In less than a month the syastem was so fouled we had to acid clean the condensers on chiller just to get a tube brush through the 5/8 tubes. Imagine what can happen to a Plate and Frame.

I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int.

 

[rmw]

PHE's make the best strainers in the world. If you don't put a good strainer in front of them, they will become your strainer.

Be sure to design your system so that the PHE velocities stay high. When velocities slow down in PHE's they foul. When they stay high, the tortuous paths have a 'self cleaning' effect.

rmw

 

[StoneCold]

cammax
You might be able to get some of your performanc back by flushing the exchanger backwards with clean water and then possibly with 10wt% hot citric acid.


Goodluck.
StoneCold

 

[cammax]

Thanks for the replies, In the past I have seen plate and frame HX used with brine cooling towers, but the plates where large 1"+ in thinkness, this is the first install I have seen with 277 .44mm plates on a open cooling tower design.

agian thanks for the replies

 

[plateheatexchangers]

Hi, I work in the heat exchanger business and have cleaned out many heat exchangers on cooling towers - the Alfa Laval M15B is very common on this application but as you have experienced if you don't have a decent filter the plates will foul up very quickly. With a decent filter fitted however they can run for years and years without any problems and because they are on a low temp application the gaskets last for years as well. I would say on average PHEs used in this application go about 10 years before they need servicing. So my advice would be not to blame the heat exchanger too much but get a decent filter fitted. Hope this helps in some way, good luck..

 

[plateheatexchangers]

sorry I forgot one thing - you should be very careful using acid to flush the heat exchanger as the acid will attack the plates (which are usually 304SS on this application). Also when washing the plates down do not use a wire brush as the scratched left increase the surface area for the scale to build up onto and the PHE will scale up quicker than it did before. Better to use a jet wash and a soft plastic brush, or better still have the plates chemically dipped in tanks by a specialist, there are plenty about....thanks