MIT Proto Ventures | Fusion & Clean Energy

Coating for fouling resistance in heat transfer surfaces

4 min read

Description of capability

Mike Short has developed a coating that prevents fouling by metal oxides, aka “crud”, on hot surfaces in heat transfer applications.

  • Mike’s group developed a coating with the same optical properties as the surrounding fluid, which eliminates the van der waals forces. You can coat metals or ceramics with it.
  • The research sponsors waived their right to an exclusive license. EPRI and Exelon were the sponsors and have taken a license, but not exclusive. Equinor funded it but didn’t license it.
  • Mike is also working on a $600K, two-year sponsored research project with Deep Power and Wings Fund in collaboration with the University of Iceland to apply this technology to geothermal. Deep Power will have a non-exclusive license for the area of geothermal energy.
  • $600K total funded by Wings Fund, in collaboration with University of Iceland, for two years, regular sponsored research. No new science needed. This is a “cook and look” project now. It’s all about identifying new coatings that can last at low pH. Wings is funding work at Oklahoma and UCLA. The startup is called Deep Power.
  • Since the Langmuir publication, three materials identified that work even better, including tetrahedral amorphous carbon.
  • They have verified that these materials work at 150 atm at 350 ºC.
  • Testing has involved:
    • Flowing corrosion loop for 1-2 months, fast flowing water and boiling
    • Stuck them in the MIT reactor for 6 months (albeit no heat flux)
    • Some of the materials from the paper didn’t survey (e.g. zirconium nitride) didn’t survive in the nuclear environment.
  • The effect works primarily in regions where VdW forces dominate. These are typically high-temperature applications where the electrostatic interactions dissipate. So it’s perfect for nuclear and other applications where the water is high-temperature and high-pressure.
  • In other applications, if these specific coatings don’t work, others probably would.
  • They also did a study to investigate if you could coat every nuclear fuel rod in the country. It would cost 10 per rod.
  • Commercialization next steps:
    • For each potential market, estimate: how much value would this add?
    • We know it adds value in nuclear, but the testing is hard. You need to get a reactor owner to take a risk and put this new material into their reactor for several years (Mike has made some progress with the Constellation Energy and the Candu Owners Group in Canada). Constellation provided $4M of research
    • For geothermal, the water is much more acidic (pH ~ 3). We are closer to reaching a deal with the commercial partner.
    • Where else? Apparently oil & gas (see Mike’s conversation with Saudi Aramco)
  • Timeframes:
    • If a coating lasts 4.5 years, it meets the criteria. But even if staves off CRUD formation for ~300 days, you may still avoid the tipping point where it becomes a problem.
  • Applying the coating:
  • Who makes the nuclear fuel rods? Westinghouse and 2-3 other companies
  • How expensive is it to build the coating equipment?
    • The design study showed that the machine would cost $10-20M

Note: A company called Nanofilms does all the anti-stick coatings for all Apple products. It’s amorphous carbon. Mike believes you could use this technology to coat narrow-diameter components like heat exchanger pipes.

Key people

Mike Short

Technology Readiness Level (1-9)

  • Patents got granted a few weeks ago.
  • Mike is trying to convince a fission plant to put this in a reactor for testing.

Needs that this could potentially address

Tech specs

Works on any large heat exchanger above 200 ºC.

Estimated time & cost to commercialize

Outstanding risks

  • Durability of the coatings at low pH
  • Competition: according to Minhaj Malik, people have done versions of this with CVD and tubes, PVD, ion vapor and related techniques. Solutions exist in the market.
  • Suitability to surface heat exchangers, where the coating would presumably need to be applied inside cylindrical tubes

References

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