For as long as heat exchangers have existed, industrious engineers have been seeking ways to overcome fouling’s negative impact on efficiency.
The standard response to fouling is to flush the exchanger with aggressive chemistries or scour the unit with pressurized water or steam. While these approaches often restore performance to some degree, they also cause serious difficulties. For instance, cleaning a heat exchanger is disruptive, and the results are frustratingly temporary even after heavy cleaning.
An alternative technology worth considering is Exchanger Industry Limited’s proven antifouling coatings.
Fluoropolymer coating applied to the tube-side of a heat exchanger decreases the unit’s susceptibility to fouling – in essence, preventing material deposition before it happens. This solution eliminates the need for aggressive cleanings; however, there are a few things to consider before committing to the upgrade.
The Ongoing Costs of Heavy Fouling
The direct costs to resolve heat exchanger fouling are evident, as they’re either related to cleaning or prevention. It’s the indirect costs—the inefficiencies, quality impacts and safety implications—that, while every bit as real, are more challenging to nail down.
These indirect costs include, but are not limited to, the following:
- Inconsistent or unstable exchanger duty
- Increased fuel costs tied to elevated pressure drop
- Quality impacts on downstream processes
- Safety & environmental considerations for both cleaning and disposal activities
- Wear and tear on the unit (due to frequent cleaning and maintenance)
- Inflated capital costs from oversized or redundant units
Determining the total cost of exchanger fouling for your heat transfer process isn’t straightforward. However, partnering with an industry specialist makes calculating both direct and indirect costs easier.
Working hand-in-hand with your engineering, operations or maintenance team, Exchanger Industries Limited will help quantify the return on investment (ROI) for your solution.
Cleaning as a solution
A wide variety of industries, including oil production, food processing and desalination, regularly deal with heavy fouling. The typical response is to clean-in-place (CIP) with diminishing returns or forego CIP altogether in favor of regular mechanical cleaning.
Mechanical Cleanings
Hydroblasting or wire brushing physically removes scale, algae, solids and salts from heat exchanger tubes and generally returns the unit to a near-clean condition. The downside, of course, is that the unit must be opened up to access the tubes, meaning heavy equipment and extended downtime. On top of this, there’s the inherent risk of equipment damage, inevitable tube wall loss and accelerated wear and tear on the unit that all act to shorten the expected life of your assets.
Chemical Cleanings
Chemical cleanings dissolve and flush foulant from heat exchanger tubes. The solvents span the extremes of the pH spectrum, with both highly caustic (ex. sodium hydroxide) and highly acidic (ex. hydrochloric or hydrofluoric acids) solutions seeing common use. This type of cleaning involves aggressive chemicals with their associated safety risks and hefty disposal costs, not to mention downtime.
As long as fouling is addressed with cleaning (which only eases the severity of the problem), the issue will never be truly “solved.” Instead, consider a strategy that prevents the situation in the first place.
Antifouling Coating as a Solution
Exchanger Industries’ leading-edge antifouling coating is effective, long-lasting and – thanks to its unique fluoropolymer chemistry – imparts antifouling properties to the heat exchanger itself by repelling substances at the molecular level.
This proprietary technology has proven itself over multi-year testing in heavy-fouling oil sands applications, allowing heat exchangers to function at their initial efficiency from day one onward.
Additional advantages include:
