Desuperheater Application Best Practices
An ever-increasing need for steam at specific temperatures and pressures exists in many modern plants. Fortunately, significant improvements have been made to increase operational thermal efficiency and heat rates by the precise, coordinated control of the temperature, pressure and quality of this steam. But, much of the steam produced in power and process plants today is not at the required conditions for each application, so conditioning is required, often by a desuperheater system.
The sizing, selection, application, installation and maintenance of the proper desuperheating and steam-conditioning equipment, including control valves, is therefore critical to optimum performance. This article will discuss superheaters and associated control valves in detail, but first I will look at common applications and issues in affected industries.
Competing in the modern power market requires a heavy emphasis on the ability to utilize multiple operating strategies. Increased cyclical operation, daily start-stop and faster ramp rates are required to ensure full-load operation, particularly at daily peak hours, and to maximize profit and plant availability. Changes resulting from environmental regulations and economics also are combining to alter the face of power production.
At the same time, these changes are affecting the operation of existing power plants and the design of future plants. Advanced plant designs include requirements for increased operating temperatures and pressures along with stringent noise limitations in urban areas. Steam is used throughout power plants in many ways, from driving to turbines to feedwater heaters.