“Innovation distinguishes between a leader and a follower.” – Steve Jobs
Introduction: The ACC are an integral part of power plants, and their effective passivation directly impacts plant efficiency and operation. Traditionally, ACC’s posed a challenge due to their large surface area and associated contamination. But with innovative approaches such as SigmaCommissioning™ protocols by BEST Energy Services, Inc., these challenges are being addressed head-on.
The ACC Challenge: ACCs have a significantly more extensive surface area than their water-cooled counterparts, attributed to air’s poor heat transfer properties. Consequently, these condensers have proportionately higher surface contamination, including debris and surface oxidation. Even with factory cleaning, the post-construction phase leaves ACCs with a substantial contamination footprint, leading to complications like fouling of condensate suction strainers and contamination of deaerators and collection tanks.
Conventional Cleaning Limitations: Traditional cleaning methods for ACCs often lead to extended periods on bypass post-steam blow restoration. This not only means extended wait times to meet steam turbine admission requirements for chemistry but also substantial economic implications in terms of gas costs and lost capacity/generation payments.
Enter SigmaCommissioning™ Protocols: BEST Energy Services, acknowledging the limitations of conventional methods, innovated the SigmaCommissioning™ protocols. This three-phase protocol ensures a comprehensive ACC preparation:
- High Velocity Water Flush: This initial phase involves a rigorous water flush of each ACC street, tube, duct, condensate collection headers, and return piping using specialized BEST flush nozzles. The aim is to remove gross debris in preparation for steam admission. By recycling water with filters and collection tanks, water usage is minimized, ensuring environmentally conscious operations.
- Positive Pressure Test: Instead of the conventional vacuum approach, BEST employs a positive pressure test. This method proves far more effective in identifying vacuum leaks due to the reduced background noise and evident leak indicators, ultimately saving crucial schedule days.
- Steam Wash & Passivation during SigmaBlow™: The crowning phase involves steam washing and passivating the ACC. By allowing for closed cycle operation during the steam blow, the SigmaBlow™ process supports varying load ranges, including baseload operation. Steam treated with agents such as Carbohydrazide, Ammonia, and Monoethanolamine is directed to the ACC, promoting the formation of passive magnetite on carbon steel surfaces. As a result, post-restoration time to achieve steam chemistry is drastically shortened from weeks to mere days.
Conclusion: By adopting BEST Energy Services’ SigmaCommissioning™ protocols, power plant operators can significantly improve their ACC passivation process, ensuring efficient operations and substantial economic benefits. The comprehensive approach ensures thorough cleaning and passivation, setting a new standard for the industry.
Contact: For further information and deep dives into BEST Energy’s solutions, visit www.bestenergyservices.com or contact at +1 603-227-5200
Reference: Technical Application Note – 022, R20220628, BEST Energy Services, Merrimack, N.H. 03054.