Helping you prepare for tomorrow

HRSG Assessments

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.

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Assessment for gas turbine (GT) upgrade

If you increase the energy input to your HRSG as a result of a GT upgrade, you may need to make certain modifications to remain compliant with the boiler code requirements and the local regulations, while also ensuring proper function of affected components.

GE’s engineers can model the performance of your HRSG along with the new GT exhaust conditions to identify any areas of concern. HRSG components that typically require modification in conjunction with a GT upgrade are feedwater control valves, desuperheaters and safety valves. GE can also provide a turnkey solution for the recommended modifications.

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Assessment for Change in Operation

Do you have an HRSG that was originally specified to operate at base load but you are now being asked to cycle your GT and operate for extended time at low loads? GE’s engineers can model the performance of your HRSG at the new operating conditions and identify any areas of concern. GE can also provide material and field services for any recommended modifications.

Helping you make the most of your plant

HRSG flexibility solutions

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.

Final Stage Attemperator (Desuperheater)

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

Additional HRSG solutions

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.

I need to resolve an HRSG issue that isn’t mentioned above. Can GE help?

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.