Research Team Creates Steam Condenser Coating
Researchers at the University of Illinois Urbana-Champaign have reportedly developed a coating for steam condensers used in fossil fuel steam-cycle generation.
According to the a release from UIUC's Grainger College of Engineering, this innovation to the steam cycle for fossil fuel power generation could help achieve 460 million fewer tons of carbon dioxide released, as well as 2 trillion fewer gallons of water used during the process.
Researchers stated in the journal Nature Communications that this coating, made with fluorinated diamond-like carbon (F-DLC), could boost the overall process efficiency by 2%. Additionally, they reportedly demonstrated the coating’s suitability for industrial use by performing the longest durability test ever reported.
Steam condenser coating could save 460 million tons of carbon dioxide annually https://t.co/yMhWb9w6XZ— Forum Futur (@forum_futur) August 24, 2023
"The reality is that fossil fuels aren't going away for at least 100 years," said Nenad Miljkovic, a professor of mechanical science and engineering at UIUC and the project lead.
"A lot of CO2 is going to be emitted before we get to a place where we can lean on renewables. If our F-DLC coating were adopted globally, it would noticeably curtail carbon emissions and water usage for the existing power infrastructure."
The researchers explain that their new F-DLC coating can improve heat transfer since the material is hydrophobic. When the steam condenses into water, it does not form a thin film that coats the surface in the way water does on many clean metals and their oxides.
Instead, according to the release, the water will form droplets on the F-DLC surface, putting the steam into direct contact with the condenser and allowing heat to be directly transferred. Researchers stated that this improved the heat transfer properties by a factor of 20, translating to a 2% overall process boost.
"It's remarkable that we can achieve this with F-DLC, something that just uses carbon, fluorene and a little bit of silicon," said Muhammad Hoque, a postdoctoral research associate and the study's lead author. "And it can coat pretty much any common metal, including copper, bronze, aluminum and titanium."
To demonstrate F-DLC’s durability, the researcher said that they subjected coated metals to steam condenser conditions for 1,095 days, the longest test reported in the literature.
The coated metals reportedly maintained their hydrophobic properties for the entire length of time. Additionally, the researchers found that the coated metals maintained their hydrophobic properties after 5,000 scratches in an abrasion test.
According to the release, the research team is now collaborating with UIUC’s Abbott Power Plant to study the coating’s performance for six months of “steady condensation exposure under industrial conditions.”
"If all goes well, we hope to show everyone that this is an effective solution that is economically viable," Miljkovic said. "We want our solution to be adopted, because, although the development of renewable energy should absolutely be a priority, it's still very worthwhile to continue improving what we have now."
Other Pipe Coatings
Earlier this month, researchers from the National Energy Technology Laboratory (NETL) developed a new self-healing cold-spray coating for internal pipeline corrosion protection.
According to the release, the invention can help protect against corrosion in natural gas, hydrogen and carbon dioxide pipelines, preventing failure events such as explosions and methane emissions.
NETL’s Ömer Dogan, who worked on the innovation, stated that internal pipeline corrosion is a common problem. Dogan worked alongside NETL researchers Joseph Tylczak, Margaret Ziomek-Moroz and Zineb Belarbi.
The release explains that traditional approaches to fighting pipeline corrosion include the use of inhibitors or organic coatings such as fusion-bonded epoxy and polyurethane. However, the challenge with the injection of inhibitors in natural gas or carbon dioxide pipelines is reportedly the difficulty of transporting the inhibitor along the pipelines.
Dogan stated that another approach would be to use sacrificial coatings, or anodes, to protect the pipelines and equipment from internal corrosion. The anode reportedly undergoes oxidation more than the metal surface it protects, essentially stopping oxidation on the metal. However, Dogan said that these anodes tend to dissolve too fast in natural gas pipelines.
According to the release, cold spray is a high-energy solid-state coating and powder consolidation process for applications of metals, metal alloys and metal blends. Cold spray reportedly uses an electrically heated high-pressure carrier gas, similar to nitrogen or helium, to accelerate metal powders through a supersonic nozzle for particle adhesion.
The coating can reportedly be applied to the interior of a pipeline through the use of a robotic cold spray device attached to a pipeline pig.
The report adds that some of the features of the zinc-rich coating include: