Horizontal Gas Flow Arrangement Drum Type
The typical STF design for HRSG is based on the horizontal exhaust gas flow arrangement, cold casing sealed walls, vertical heat exchanging bundles with finned tubes.
The HRSG recovers the waste heat from hot combustion gas discharged from the gas turbine and produces the steam by natural circulation.
The main features of STF horizontal Heat Recovery Steam Generators include:
- Range of HP steam production from 40 t/hour to 320 t/hour.
- One to three levels of pressures up to a maximum steam operating pressure of 150 barg and 575 °C temperature.
- Casing internally insulated (cold casing) with external ribs and stiffeners.
- Top supported heating elements, with finned tubes in staggered configuration to optimize thermal design, free to expand downward at any load and transient condition of the HRSG.
- Efficient natural circulation of the water/steam fluids, streamlined by small diameter of the finned tubes to minimize level fluctuations of the drum.
- Steam de-superheating systems, with temperature controlling, before super-heater and re-heater final sections.
- Provision of features to allow fast start-up, easy operation and maintenance of the unit, tailored to Client requirements.
- Option for post firing system with suitable burners, with or without fresh air and associated fresh air fans.
- Option for de-NOX Selective Catalyst Reduction system (SCR), including ammonia injection and distribution system and its accessories.
- Design and installation/optimization of any other provision for achieving of contractual technical requirements and performances of the HRSG, in full accordance to Client’s requests.
- Full assistance to the Client during and after the warranty period, in terms of quick response to technical queries, site intervention, upgrading of technology.


