Schroedahl Type DKT Steam-Atomizing Desuperheater
Product Features
- Suitable for difficult operating conditions, high quality temperature control and avoidance of temperature shocks (valve and piping)
- Allows cooling operation when all other systems typically fail
- For optimum temperature control close to saturation with a control ratio of up to 100:1
- Ultimate cooler for low-speed steam cooling applications, large bandwidth and small distance/separation to saturation
- The additional cooling water and atomizing steam control valve must be considered in the planning
Applications
- For low speed, highly adjustable desuperheater applications and low saturation separation.
Nominal diameter: DN 150-800 / NPS 6-32
Pressure Class: PN 25-250 / Class 150-1500
Product Features
- Suitable for difficult operating conditions, high quality temperature control and avoidance of temperature shocks (valve and piping)
- Allows cooling operation when all other systems typically fail
- For optimum temperature control close to saturation with a control ratio of up to 100:1
- Ultimate cooler for low-speed steam cooling applications, large bandwidth and small distance/separation to saturation
- The additional cooling water and atomizing steam control valve must be considered in the planning
Applications
- For low speed, highly adjustable desuperheater applications and low saturation separation.
Technical Data
| Nominal diameter | DN 150–800 / NPS 6-32 |
| Pressure class | PN 25–250 / Class 150–1500 |
| Temperature (max.) |
Up to 650°C / 1200°F |
| Housing material | 1.0460 / A105 1.5415 1.7335 / A182F12CI.2 1.7383 / A182F22CI.3 1.4903 / A182F91 |
| Housing type | Forged |
| Media | Superheated Steam, Gas |
| Flanges | EN 1092-1, ASME B16.5, ISO 7005, JIS, JPI, welding ends on request |
| Number of stages (max.) | 4 (water side) |
| Number of controlled stages (max.) | 4 (water side) |
| Operating range (max.) | 1:100 (water) |
| Other | Type DKT requires an injection pressure control valve AK or AV |
Function
Desuperheating (cooling) the steam can simply be achieved by injecting water into the steam flow. When injected, the water is evaporated by means of the desuperheater nozzles. Thereby the water absorbs heat and consequently the temperature of steam is reduced. The desuperheater is designed so that a very fine atomisation (mist) is achieved even when injecting very small amounts of atomising steam. This both minimizes the distance required for cooling and homogenizing the steam and guarantees reliable cooling until close to the saturation point.
The good homogenisation and rapid evaporation means that no additional protective pipes are required in the steam line.
Cooling medium is introduced into the nozzle head via an injection valve. In the nozzle chamber inside the nozzle head the medium is accelerated and rotated by a swirl insert, so that a spray mist develops when it exits into the steam line. The atomising steam is introduced into the steam line through holes arranged around the nozzle. This atomises the water droplets to a very fine mist that evaporates very rapidly.
