Silent Threat: Sulfuric Acid Corrosion in Combustion and Exhaust Systems
Did you know?
Did you know sulfuric acid can silently corrode carbon steel, leading to operational setbacks and costly repairs? Sulfuric acid formation poses a significant challenge in combustion and exhaust systems, particularly in those using fuels with sulfur content.
Photo showing sulphuric acid deposits in HRSG
The Hidden Culprit
During combustion, sulfur present in the fuel—either naturally occurring or added by suppliers for odorization (e.g., mercaptan in natural gas)—undergoes chemical conversion. This process produces sulfuric acid vapors, which condense under specific conditions, forming stubborn deposits.
Why It Matters?
In coal-fired plants and many HRSGs (Heat Recovery Steam Generators) firing liquid fuels, particulates typically carry the condensed sulfuric acid out with the flue gas. However, in natural gas systems, the absence of particulates means the acid condenses onto cooler components, creating sticky, hygroscopic deposits that:
Corrode tubes and other steel surfaces
Obstruct GT flue gas flow, increasing backpressure and reducing gas turbine power output
Accumulate over time, potentially weakening steel and causing tube bursts
How can Tetra Engineering help?
At Tetra Engineering, we specialize in identifying and mitigating the root causes of deposit formation. Our fouling assessments analyze critical parameters, including:
Acid dewpoint temperature
Fuel sulfur content
Exhaust gas temperature
Boiler inlet water temperature
Using advanced thermodynamic simulation software (PPSD), combined with industrial best practices and scientific methodologies, we provide actionable solutions tailored to your system. Whether immediate cleaning is required or operational adjustments can mitigate deposit buildup, our experts are here to help.
Protect Your Operations
Safeguard your equipment, optimize system efficiency, and prevent costly downtime. Tetra Engineering'’s mission is to ensure clean boilers, seamless operations, and uninterrupted power generation.
Contact us today to learn more about our fouling assessment services and keep your systems running at peak performance!
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Our goal is to protect the value of your investments and improve the performance of your assets.
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