Efficient Heat Transfer
Superheated steam is pressurized water that is at a temperature higher than the saturation. Although process steam is typically throttled and superheated for efficient distribution, it must be cooled before it is condensed and therefore it is less efficient than saturated steam for a majority of heat transfer operations. The most efficient way to reduce the superheat value of steam is to “desuperheat” it. This involves direct introduction of water into the steam stream.
Turbine bypass desuperheaters play a major role in power plant applications. Within a period of twenty-four hours, a Power Plant may be required to operate at minimum load, increase to maximum capacity for major part of the day, immediately cut back to minimum load and then back to maximum capacity. Bypass Systems permit unit-start up and unit-shutdown for critical heavy components in boilers and turbines. Bypass Valves are supplied with hydraulic, electric or pneumatic actuators as per the process requirements, along with complete control systems as an option.
There are two basic applications for bypass desuperheaters:
- When bypass systems are intermittently in operation to include startup and shutdown conditions and emergency conditions
- When bypass systems are permanently in operation, for example for process steam or heating applications.