Fouling factor

[Joget005]

Hi,

I am handling a fin fan cooler and 1 of the potential bidders I have states that they will not confirm fouling factor for the tube side as it is by process licensor so they say. I find this quite unusual. Can someone help me, please?

 

[SNORGY]

I would say that they have a point, but that they should take a guess at it based on their experience and on what they consider to be a fouling service. All you should need to tell them is whether it is wax, coking, residue or corrosion that drives the fouling on the process side.

Regards,

SNORGY.

 

[rmw]

Then tell them that you can't evaluate their bid and are going to have to toss it. See if they come clean then.

rmw

 

[TD2K]

I would say they have a point. I've never left the fouling factor up to the vendor to set. They don't know the process other than what you put on the data sheet.

A fouling factor is a double edged sword. Yes, it does give you additional area which will compensate for the loss of heat transfer due to fouling. However, the increase in area also comes at the cost of reduced velocity (because more area = more tubes) which directionly isn't what you want to reduce fouling, depending of course on the type of fouling.

 

[Joget005]

Thanks guys for all your answers. I have however indicated the fouling factor in the datasheet.

 

[Latexman]

You gave the fouling factor. They will not confirm it, i.e. they will use your value. That's all.

Good luck,
Latexman

 

[speco]

If the vendor doesn't show what fouling factor they have used in their design, they probably aren't a very reliable vendor. Generally, the more complete their data sheet is, the better. I would be suspicious of any vendor that doesn's show it on their data sheet.

Regards,

Speco

 

[rmw]

Additional area could come at the expense of pressure drop in that instead of adding tubes, they might just lengthen the Hx.

rmw

 

[rakuday]

Hi,

Since you have not given the details of the process, when you specify the fouling factors, have a mental note of how the FF affects the cooler design as a whole (in addition to the increased area).
1. Increases pressure drop of the process fluid
2. Will have to increase the velocity of the process fluid to compensate the increased cooler length
3. With an increased area, chances are the fan motor will fall into the higher range, thereby leading to bigger fans and higher energy consumption
4. So be judicious in selecting the value of the FF
5. Also, in view of the location of the coolers (for any airborne particles), evaluate the option of using air side fouling factors too.

Thanks