Puerto Coronel (Colbun) (Chile) - 1x1215 t/h
Project of new 1×370 MWe unit construction with dry bottom furnace boiler in Puerto Coronel Power Plant (Chile).
| Project Data: | |
| Client: | Colbún S.A., Las Condes Santiago |
| Operator: | Colbún S.A. |
| Location: | Puerto Coronel, VIII. Region |
| Country: | Chile |
| Contract: | 06/2007 |
| Handing-over: | 06/2010 |
| Suppliers – Members of Consortium: | |
| Head of consortium: | MAIREENGINEERING S.p.A. Torino (Italy) |
| Technical leader of consortium: | MAIREENGINEERING S.p.A. Torino (Italy) |
| Supplier of boiler house: | SES, a.s., Tlmače (Slovakia) |
| Supplier of turbine hall: | MAIREENGINEERING S.p.A. Torino (Italy) |
| Supplier of turbo-generator: | General Electric (USA) |
| Technical Parameters: | |
| Maximal continuous rate: | 1215 t/h |
| Superheated steam pressure: | 17,2 MPa |
| Superheated steam temperature: | 541 °C |
| Nominal temperature of feed water: | 292 °C |
| Inlet pressure of reheated steam: | 4,45 MPa |
| Outlet pressure of reheated steam: | 4,25 MPa |
| Inlet temperature of reheated steam: | 347 °C |
| Outlet temperature of reheated steam: | 541 °C |
| Fuel: | bituminous coal |
| Lower calorific value: | 23,96 – 28,89 MJ/kg |
Boiler Design
- Double-pass boiler with natural circulation and dry bottom furnace. Boiler walls are gas tight, membrane type with vertical tubes, formed by evaporator and wall superheaters.
- The whole pressure system is suspended on the ceiling of the boiler supporting structure.
- Feed water enters the economizer and then led to the boiler drum. It is led through downcomers into lower headers of the evaporator. The steam-water mixture from the upper headers of the evaporator is led back to the boiler drum.
- Saturated steam from the boiler drum is led to the steam superheater. The steam superheater is formed by a system of wall superheaters and three bundles of convectional and radiation heating surfaces.
- The superheated steam temperature is controlled by feed water injection.
- The steam reheater consists of two stages.
- The reheated steam temperature is controlled by means of so-called regulation pass by injection of feed water extracted from the intermediate stage of the feeding pump.
- For cleaning the combustion chamber walls there are used jet-spray blowers and for cleaning the other heating surfaces in the boiler convectional pass there are used long-retractable steam soot-blowers.
Combustion Equipment of Boiler
- Combustion equipment of the boiler consists of four milling loops. Each of the milling loops consists of a coal bunker, a coal feeder and a mill.
- In the front wall of the combustion chamber there are 16 swirler low-NOx pulverized fuel burners. The burners are arranged in four rows above each other. In each row there are 4 burners situated next to each other. In each burner row there is led pulverized coal from one mill. In the centre of each burner there is an oil burner used for starting-up the boiler and supporting combustion at low output.
- The air-flue gas system consists of two branches: two axial flow pressure air fans, two steam air heaters, Ljungströms, electrostatic precipitators of ash, ID fans. Combustion air is heated in two triple-section regenerative air heater of Ljungström type.
- The boiler is provided with four middle-run mills arranged in a row near the front wall of the boiler.