As the contribution of renewable energy sources grow on electrical power grids, so does the cycling its intermittency creates for power producers. This cycling affects steam used to drive the generators.
For power stations where the electric generators are steam-driven, this steam is created by coal, nuclear, geothermal, solar thermal, waste incineration and sometimes natural gas. Boiler tube leaks caused by frequent cycling affect reliable operations.
In this 2:46 YouTube video, Overcome Tube Leak Problems with Better Steam Temperature Control, Emerson’s Mike Painter describes how boiler tube leaks and temperature excursions can be minimized with a better approach to controlling attemperation and steam temperature.
Mike highlights three areas on which to drive reliability improvements:
- Ensure temperature measurement accuracy
- Implement model-based temperature control
- Improve steam attemperation
One approach for improve accuracy is using a temperature transmitter which senses both thermocouple degradation and drift.
With model-based control, the response time of the overall process can be captured to be able to apply a precise control strategy to reduce variability and valve actuation, and operate closer to constraints and not exceed thermal limits.
Without the proper spray valve performance, the superheater and reheater loop is more prone to variability. This condition risks impingement damage to the heat exchanger and steam turbine. Severe-service valves and regular attemperator inspections can help improve reliable and efficient operations.
You can connect and interact with other temperature measurement experts in the Temperature group in the Emerson Exchange 365 community and at the October 1-5, 2018 Emerson Exchange conference in San Antonio, Texas.