Client: Super Major Refinery (Baytown, USA)
Equipment: Waste Water Stripper Feed Heater 163-32-504
Curran Products: Curran 1500, Curran 1000T, Viton topcoat
The Challenge: Fouling and Corrosion in Critical Heat Exchangers
Heat exchangers are vital components in petroleum refineries, power plants, and chemical processing facilities. However, these assets are constantly exposed to harsh operating conditions, leading to persistent challenges such as fouling and corrosion. These issues directly impact thermal efficiency, reduce throughput, increase energy consumption, and necessitate frequent cleaning and maintenance, ultimately shortening the service life of equipment and impacting operational reliability.
For Super Major Refinery, a Waste Water Stripper Feed Heater (163-32-504) presented a typical scenario of age-related wear, exhibiting pitting on the tube sheet surface. Such degradation compromises the integrity of the heat exchanger and, if left unaddressed, can lead to premature failure, unplanned downtime, and significant repair or replacement costs. Addressing these issues effectively and proactively is crucial for maintaining continuous, efficient plant operations.
The Solution: Curran’s Advanced Coating System
Curran International was engaged to repair and protect the tube sheet of the client’s heat exchanger using a multi-layer coating system. The objective was to mitigate further corrosion, enhance surface durability, and extend the operational lifespan of the unit.
The scope of work included:
- Surface Preparation: The tube sheet surface was prepared to white metal cleanliness with an appropriate anchor profile to ensure optimal coating adhesion.
- Pitting Repair: Pitted areas on the tube sheet and gasket surfaces were rebuilt using Curran 1500, then ground flush to grade.
- Base Coat Application: Curran 1000 was applied to the entire tube sheet at a dry film thickness (DFT) of 30-40 mils over the Curran 1500.
- Topcoat Application: A Viton topcoat was applied to the coated surface at 4-8 mils DFT, extending into the tube ends (1″-2″).
- Quality Control: A 100% holiday test was performed on the coated surface, and the coating application was force cured in a shop oven.
The following images illustrate the condition of the exchanger as received, after blasting, and after the initial application of Curran 1500:
As-Received Condition
After Blasting
After Curran Coating Application
Results and Operational Impact
The application of Curran 1500 and 1000T coatings provided this Gulf Coast Refinery with a robust solution to enhance the reliability and extend the service life of their critical heat exchanger. While specific long-term operational data for this particular unit is still being gathered, previous applications of Curran’s coating systems in similar industrial environments have consistently demonstrated significant improvements:
- Extended Run Lengths: Curran coatings have enabled heat exchangers to operate for extended periods beyond their previous runtimes, significantly reducing the frequency of maintenance shutdowns.
- Reduced Fouling: The smooth, durable surfaces created by Curran 1000T mitigate fouling accumulation, maintaining thermal efficiency and reducing the need for intensive cleaning.
- Corrosion Protection: Curran 1500 and 1000T provide exceptional resistance to aggressive chemical environments, protecting the underlying metallurgy from corrosion and erosion.
- Enhanced Reliability: By addressing pitting and preventing further degradation, the coatings enhance the overall mechanical integrity and reliability of the heat exchanger.
- Cost Savings: The reduction in cleaning cycles, extended service life, and minimized risk of unplanned outages translate into substantial operational cost savings.
This comprehensive repair and coating strategy by Curran International reinforces the value of proactive maintenance and the application of advanced protective coatings to critical process equipment. By leveraging Curran’s expertise, Baytown Refinery can anticipate improved asset performance and a stronger return on investment from their heat transfer equipment.