English to Italian Tech/Engineering Energy / Power Generation desuperheater

grazie, Ilde.


PARAGRAFO DI CONTESTO E UN'OCCORRENZA
A desuperheater is often installed into the plant steam piping at a location downstream of the main steam stop check valve and located before the automatic vent valve. The first steam produced by the once through steam generator is at gas temperature and often cannot be accepted by the steam turbine or process. The steam is usually vented until the desuperheater *minimum turndown* is reached and spray can be initiated to cool the steam temperature to set point. The desuperheater will provide the ability to bring the OTSG steam production into temperature control for steam line warm-up.

ALTRE OCCORRENZE
Logic is required to open the valve only after the *minimum turndown* of the desuperheater has been attained.
Limit feedwater flow to < safety valve capacity and > *minimum turndown limit*.
If flow drops below *minimum turndow*, trip desuperheater block and control valve closed
As the OTSG feedwater is ramped, the steam flow will approach the *minimum turndown capability* of the HP desuperheater.

For this project the desuperheater *turndown* will require a minimum inlet flow of 15656 lb/hr (7100 kg/hr.
The vent is used to discharge steam until the steam temperature reaches set point or until the desuperheater *minimum turndown* has been reached and the spray can commence.