Case study: Help solving a severe corrosion issue in a refinery boiler
Knovel helps an oil and gas company address corrosion, optimize boiler efficiency and avoid a $90,000 retrofitting
A large oil and gas company encountered a corrosion problem in the boilers at one of its refineries. A company process engineer used Knovel’s interactive graphing tool to discover that increasing the alkalinity of the water solution used in the boilers will inhibit corrosion. By altering the solution, the engineer was able to increase boiler efficiency, avoid condensate return issues and save $90,000 in retrofitting expenses.
The discovery of boiler corrosion created concern because worsening corrosion could increase the risk of health, safety and/or environmental incidents. Corrosion could also result in reduced boiler efficiency due to poor heat transfer, causing problems in the condensate return system that could lead to extended downtime.
The process engineer tasked with solving the problem needed to identify the root cause of the corrosion and devise a change in the process that would reduce corrosion in the refinery’s three boilers — without resorting to an expensive retrofitting of the boilers’ piping and instrumentation.
The engineer chose Knovel in his discovery process, building foundational knowledge on topics relevant to the corrosion issue and uncovering data-rich insights. He used Knovel’s Graphic Digitizer to understand the corrosive properties of metals with respect to pH and water solution speed. He also referred to alkalinity charts to find a stable pH range for the boiler’s condensate. The engineer learned that an acidic water solution will accelerate corrosion in boilers and he quickly zeroed in on a viable resolution for the refinery’s boiler corrosion problem. Operating the water solution used in the boilers at a slightly higher pH (8-9) would create an oxide layer that would serve as protective coating and minimize the formation of eroding particles.
"Steam is a substantial expense in a refinery, rising as high as $7 million annually in an average-size refinery."
By incorporating the insights he found in Knovel, the process engineer successfully inhibited corrosion in the refinery’s boilers. The new water solution optimized boiler performance and significantly reduced the risks of health, safety and environmental incidents, as well as the risks of condensate return issues and boiler stoppages. Knovel helped the engineer discover best practices with respect to water solution pH quickly, informing a critical business decision. The company avoided having to implement a retrofitting of the boilers’ piping and instrumentation, which would have cost up to $30K per boiler and $90K in total for the refinery.
"Using the information from Knovel, the engineer learned that an acidic water solution will accelerate corrosion in boilers."