Preserve Heat Exchanger Efficiency with SilcoTek's Anti-Fouling Coatings

Fouling is one of the biggest threats to heat exchanger performance. Whether it’s mineral scaling, corrosion byproducts, hydrocarbons, or biological buildup, fouling acts like a thermal blanket by adding unwanted resistance between your metal surface and the process fluid. The result? Lower thermal conductivity, higher pressure drop, and reduced energy efficiency.

At SilcoTek, we offer chemical vapor deposition (CVD) coatings that protect against fouling and corrosion without compromising heat transfer performance. Backed by data from both our internal studies and an EPRI/DOE evaluation, our coatings have proven to maintain exceptional thermal conductivity and surface integrity across even the most challenging applications.

Why Fouling Hurts Thermal Conductivity

In a typical heat exchanger, clean metal walls efficiently transfer heat between process streams. But when a fouling layer forms, it adds a new barrier with poor thermal conductivity (often 10–100× lower than the metal itself).

This added resistance slows heat transfer, forcing the system to work harder to achieve the same results. Over time, the effects cascade:

• Reduced heat-transfer coefficient: The total thermal resistance increases.
• Higher pressure drop: Deposits constrict flow, increasing energy demand.
• More frequent cleanings: Downtime and chemical cleaning costs rise.
• Accelerated corrosion: Trapped deposits can create localized attack points.

Preventing or minimizing fouling is the key to preserving a system’s thermal efficiency and that’s where our coatings excel.

How SilcoTek Coatings Help: Conformal, Thin, and Thermally Efficient

Our CVD coatings - including Dursan^®, Notak^®, and SilcoNert® 2000 - create a conformal, bonded layer that is both chemically inert and ultra-thin. This means:

• Zero measurable effect on heat transfer efficiency: The coating adds minimal thermal resistance compared to the base metal, preserving its conductivity.
• Uniform, conformal coverage: Even in complex geometries, such as tubes, fins, internal passages, the coating fully and evenly covers every surface, preventing localized fouling or corrosion.
• Durable adhesion: The CVD process chemically bonds the coating to the substrate, preventing flaking or delamination under thermal cycling.
• Surface energy control: Hydrophobic or hydrophilic properties can be used to reduce adhesion of deposits or promote dropwise condensation.

In short, our coatings don’t just resist fouling, they prevent it from sticking in the first place while maintaining pristine heat-transfer pathways.

Dursan-coated 20 foot heat exchanger tubes that were perfectly coated with our new 24-foot processing chamber, which was designed for coating new heat exchanger, condenser, and cooler tubes. 

Data-Backed Results: EPRI Study Confirms Thermal and Adhesion Performance

Independent validation from the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE) further underscores the effectiveness of SilcoTek coatings.

In the project “Investigation of Technologies to Improve Condenser Heat Transfer and Performance in a Relevant Coal-Fired Power Plant” (DE-FE0031762), EPRI evaluated nine coating technologies on titanium condenser tubes. Each was tested for:

• Thermal conductivity (ASTM E1461)
• Adhesion strength (ASTM C1624)

Results:
SilcoTek’s Dursan and Notak 2000 achieved a perfect performance rating, demonstrating both excellent thermal conductivity and superior adhesion.

These findings confirm that SilcoTek coatings:

1. Maintain high thermal conductivity, adding virtually no barrier to heat flow.
2. Exhibit strong adhesion, ensuring long-term durability under steam and condensation cycling.
3. Provide complete, conformal coverage that is critical in tube bundles and internal passages where uniformity drives consistent heat transfer.

Real-World Example: Fouling Reduction = Efficiency Gains

In laboratory fouling tests using synthetic seawater with calcium sulfate, an aluminum sample coated with Dursan demonstrated a 74% improvement in pressure-drop performance compared to uncoated aluminum.

That means less fouling buildup, smoother flow, and sustained thermal efficiency over time. For operators, this translates into:

• Longer cleaning intervals
• More stable process temperatures
• Reduced energy costs
• Extended equipment life

Where SilcoTek Coatings Make the Most Difference

Our coatings enhance performance across a wide range of heat-transfer applications, including:

• Power generation: Steam condensers and feedwater heaters
• Chemical processing: Shell-and-tube and plate exchangers in corrosive media
• Oil & gas: Fouling-prone crude and amine exchangers
• Pharmaceuticals & food processing: Clean-in-place systems where inert surfaces prevent cross-contamination
• HVAC and waste heat recovery: Aluminum or stainless coils exposed to humid or corrosive gases

Wherever fouling and corrosion threaten system performance, SilcoTek coatings help maintain long-term thermal conductivity and equipment reliability.

Conclusion

Fouling is inevitable but performance loss doesn’t have to be. By combining conformal, ultra-thin CVD coatings with proven anti-fouling and corrosion-resistant properties, SilcoTek helps our customers preserve high thermal conductivity and extend operational life of their heat-transfer equipment.

The EPRI study confirms what we’ve seen in the field: SilcoTek coatings perform where others fail, delivering measurable thermal and operational advantages.

Ready to improve your system’s thermal performance?

Contact our technical team to discuss how SilcoTek coatings can be applied to your heat exchanger or condenser surfaces.

Reference: 

Howell, Andrew. 2021. DE-FE0031762 Status Report. Investigation of Technologies to Improve Condenser Heat Transfer and Performance in a Relevant Coal-Fired Power Plant. Electrical Power Research Institute. https://netl.doe.gov/sites/default/files/netl-file/21TPG_Howell.pdf.