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There are a lots of air finned coolers and condensers in our refinery. The size of air finned H/X is around 10M*12M, 5-7 layers.
We had tried water jet cleaning, chemical foam cleaning, liquid nitrogen cleaning method to clean the air fins, but not satisfied to operation teams.
Could you please advise?
 
Answers
23/09/2009 A: Marcello Ferrara, ITW SrL, mferrara@itw.it
What type of fouling are you expecting in those AFCs ?
Which Unit they belong to ?
We might study the case and, if applicable, proposing you our Online Cleaning technique.
23/09/2009 A: Mike Watson, Tube Tech International Ltd, mike.watson@tubetech.com
Tubetech has experience in using all systems you mention.
Water Jet Cleaning (on up / down draft fin fans)
Can be cleaned from above but must be with low pressure and relatively high volume water BUT cannot penetrate between the fins more than 2 rows deep due to deflection.
Hence limited in its success.
If the lower rows of fins are not too fouled then cleaning is recommended from below, ie isolate and access the plenum from below with scaffolding BUT downside is that the unit must be isolated.
Chemical Foam (From top only)
Relies on foam spread evenly across top of fins to permeate through the fins. BUT if fins too fouled i.e. too restricted and deposit bridging it will not clean sufficiently after water flush.
Pressurising the foam can sometimes assist BUT is normally used when fins are lightly fouled
Liquid Nitrogen
Operates much the same as Ultra High Water Pressure, while more costly and bulky equipment wise, it has no secondary waste, BUT such pressure will buckle or cut the fins if you get too close. Close proximity is required with Liquid N hence the danger to the fins.
We would recommend our patented new build Fin Fan. Fins are cleaned ONLINE thereby maintaining cleanliness, avoiding downtime, no fin damage/corrosion, improving production, reducing internal tube surface hot spotting, reducing CO2 by reducing overall fuel consumption.