HRSGs operate under unique conditions that demand a carefully planned and executed steam blowing program. Since HRSGs are connected to gas turbines, pre-commissioning and maintenance cleaning methods must balance effectiveness with operational constraints.
What Are HRSGs?
The acronym “HRSG” stands for heat recovery steam generator. When an HRSG’s gas turbines generate electricity, they discharge a large amount of hot gases. As the name suggests, heat recovery steam generators then recover the heat energy from the hot gases to create steam, which can be used to drive a steam turbine, utilized in cogeneration or serve another purpose.
Where Are HRSGs Used?
HRSGs can be found in a variety of facilities, including:
- Chemical plants
- Combined-cycle power plants
- Refineries
- Universities
- And more
Why Do HRSGs Require Steam Blowing?
Steam blowing is performed on steam systems commonly found in power plants in order to remove mill scale, a natural part of new piping systems, weld slag and other construction-related debris prior to startup.
Steam Blowing Procedure for HRSG in Action
B&W Energy Services was contracted to perform a boiler steam blowing procedure at a 1×1 HRSG combined-cycle power plant. The client requested we perform exhaustive steam blowing for an expected duration of 30 days.
However, gas turbines aren’t well-suited for exhaustive steam blowing, as this process requires gas turbines to be stopped and started repeatedly, which can take a toll on a turbine’s lifespan. Instead, our team performed low-pressure and high-velocity continuous steam blows—the steam blowing method of choice for HRSG power projects we’ve contributed to all over the world.
Due to the newly selected steam blowing method, the estimated completion window for this project was reduced from 30 days to 7 days.
Estimated 30 Day Project
Actual Completion in 7 Days
With decades of experience performing steam blowing services on HRSG systems around the world, B&W Energy Services understands the unique challenges associated with HRSGs. Contact our team to see how customized boiler steam blowing procedures and innovative cleaning methods can help you reduce downtime, protect critical equipment and achieve faster, safer startups.
FAQs
How long does steam blowing take for a typical power plant?
Steam blowing duration varies significantly based on system size, piping complexity, chosen method and required cleanliness levels. Modern continuous steam blowing in combined-cycle power plants typically takes 1-3 weeks, while older exhaustive steam blowing methods could require several months.
B&W Energy Services has reduced HRSG steam blowing projects from estimated 30-day timelines to just 7 days by using low-pressure continuous steam blows instead of exhaustive methods that repeatedly start and stop gas turbines.
Our engineering approach segments piping systems intelligently—what might require 50 individual steam blows can often be reduced to just 5 through proper planning. Performing AquaLazing services before steam blowing further accelerates timelines by removing mill scale upfront, reducing the number of steam blow cycles needed.
Project duration also depends on available steam capacity, the number of systems requiring cleaning and whether operations can run continuously or only during specific shifts.
Do HRSGs require different steam blowing procedures than boilers?
Yes, heat recovery steam generators (HRSGs) require specialized steam blowing procedures because they’re connected to gas turbines that aren’t well-suited for traditional exhaustive steam blowing.
Exhaustive blowing requires repeatedly starting and stopping equipment to build and release pressure, significantly reducing gas turbine lifespan and increasing wear on expensive turbine components.
B&W Energy Services developed continuous steam blowing specifically to address HRSG challenges. Instead of stop-start cycles, continuous low-pressure steam blowing allows gas turbines to run steadily while achieving effective cleaning velocities through proper engineering and flow management.
This approach protects turbine investments while dramatically shortening timelines. B&W has completed HRSG steam blowing projects in 7 days that were originally estimated at 30 days using exhaustive steam blowing methods. HRSG systems also feature complex piping configurations with multiple pressure levels requiring coordinated blowing sequences.
Our team has performed steam blowing on HRSGs worldwide in combined-cycle power plants, chemical facilities, refineries and universities. Proper HRSG steam blowing requires understanding both steam system hydraulics and gas turbine operational constraints.