Heat Recovery Steam Generator (HRSG) engineered solutions

GE’s HRSG engineering team can perform a variety of assessments to help you understand the current condition of your HRSG and the impacts of your current operating regime. We can also perform additional material assessments through our site services’ metallurgical lab.

In many countries around the globe, combined-cycle plants are currently required to quickly change load and / or to operate at loads other than base load. GE’s flexibility solutions can help you meet these requirements while minimizing damage to your HRSG.

Combined-cycle power plants are increasingly required to quickly change loads based on the availability of renewable power sources. Adding a final stage attemperator to an HRSG system that only has an inter-stage attemperator will improve your ability to respond to transient load conditions.

Benefits of HRSG Attemperator:

• Decrease time to full GT load by decoupling GT and ST starts (use a combination of steam turbine bypass and HRSG attemperator spray to control the temperature to the steam turbine while it is warming up)
• Rapidly achieve minimum operating load required for emissions compliance
• Better control steam outlet temperatures during start-up and low load operation

HRSG Make Warm / Keep Warm

Maintaining metal temperature of critical pressure part components while your HRSG is shut down will help reduce stresses and life consumption on these components during transient operation.

GE offers the following options to help keep the HRSG warm during shutdown:

• Steam sparging: use steam to maintain temperature of critical components such as Drum downcomers while the CCPP is shut down
• Stack damper retrofit: Add a damper to your main stack

Addition of CO Catalyst

If you are unable to operate at lower loads because of CO emission restrictions, installing a CO catalyst may be the required solution A. CO catalyst converts CO to carbon dioxide (CO2), allowing you to further reduce CO emissions. The catalyst can be installed as a retrofit in the space available between pressure part modules.

GE’s engineers can determine the best location for the HRSG catalyst, select the appropriate catalyst for your needs, check / modify ductwork as necessary to accept the catalyst. GE can supply and install the new catalyst system.

HRSG Purge Credit

Reduce start up time by purging your HRSG during shut down instead of during start up. GE can supply hardware and installation services to modify your duct burner fuel and SCR ammonia supply systems to be NFPA 85 purge credit compliant.

HRSG purge credit is provided in conjunction with gas turbine purge credit and can be offered regardless of HRSG OEM.

Yes. GE will listen to your concerns and work with you to develop a custom, site specific solution. Since GE is a leading OEM of combined cycle power plants, we are able to develop an optimized solution for your HRSG while maintaining a holistic plant view.