Fossil Power Plants
Fossil power plants account for under 70% of the installed capacity of the CEZ Power Company (map of power plants). Brown coal is fired at most fossil power plants. The North Bohemian fossil power plants are situated in direct neighbourhood of brown coal mines.
Over the past seven years (1992-1998), the CEZ Power Company has implemented what probably is the biggest and fastest environmental programme in Europe. Within the framework of the programme, we have installed the total of 28 desulphurisation plants and 7 fluidised-bed boilers at out power plants. Moreover, ash precipitators have been reconstructed and power plant control systems have been modernised. The overall investment in modernisation and desulphurisation of fossil power plants amounted to CZK 46 billion. Thanks to the effort, the SO2 and ash emissions have been cut by 90% and those of NOX by 50%. Our power plants are thus currently fully comparable to similar sources anywhere in Europe.
The programme of modernisation and desulphurisation of fossil units of CEZ a.s.
Before the modernisation and desulphurisation programme of fossil power plants of CEZ was launched, the total installed capacity of these plants was 8,482 MW. We decided to shut down the most obsolete plants and to modernise and desulphurise the remaining facilities so that they met the new emission limits in force from 1st January 1999. The total of 6,462 MW of installed capacity have been desulphurised. For 5,930 MW of this, the so-called flue gas scrubbing technology has been used (the wet and semi-wet lime washing technologies having been applied for 5,710 MW and 220 MW respectively), 497 MW have been desulphurised by the replacement of obsolete boilers by modern fluidised-bed units and, finally, in the case of 35 MW another fuel has been used. Simultaneously with the progress of works on the cleaning of the more modern coal-fired facilities the phase-out programme for the oldest units has been launched. By the end of 1998, the total of 2,020 MW will have been phased out (diagram).
The construction of desulphurisation units in CEZ fossil power plants
| Desulphurisation units have been used for the total of 5,930 MW of installed capacity | |||
|---|---|---|---|
| Power Plant | Capacity | Method | Date installed |
| Prunerov I | 4 x 110 MW | MVV | December 1995 |
| Prunerov II | 5 x 210 MW | MVV | August 1996 |
| Pocerady | 2 x 200 MW | MVV | November 1994 |
| Pocerady | 3 x 200 MW | MVV | November 1996 |
| Ledvice | 2 x 110 MW | PSV | December 1996 |
| Tusimice 2 | 4 x 200 MW | MVV | May 1997 |
| Tisova | 100 MW | MVV | December 1997 |
| Detmarovice | 4 x 200 MW | MVV | June 1998 |
| Melnik | 720 MW | MVV | November 1998 |
| Note: MVV - wet lime washing PSV - semi-wet lime method | |||
| Programme of construction of fluidised-bed boilers in CEZ a.s. | ||
|---|---|---|
| Power Plant | Capacity | Date installed |
| Tisova | 86 MW | December 1995 |
| Hodonin | 60 MW | September 1997 |
| Porici | 50 MW | October 1996 |
| Hodonin | 45 MW | October 1997 |
| Tisova | 86 MW | November 1997 |
| Ledvice | 110 MW | October 1998 |
| Tisova | 100 MW | December 1997 |
| Porici | 55 MW | September 1998 |
In the heat and power generating plants in Dvur Kralove and Nachod (the total of 35 MW), the modernisation and suppression of emissions was accomplished by change of fuel and reconstruction of ash precipitators.
Phase-out programme of fossil units of CEZ a.s.
The total of 2020 MW of installed capacity in older coal-fired plants have been phased out.
| Phase-out programme of fossil units of CEZ a.s. | ||
|---|---|---|
| Power Plant | Capacity | Phase-out date |
| Prunerov 1 | 110 MW | January 1991 |
| Tisova 2 | 100 MW | January 1991 |
| Tusimice 1 | 110 MW | June 1991 |
| Prunerov 1 | 110 MW | January 1992 |
| Tisova 2 | 100 MW | January 1992 |
| Tusimice 1 | 110 MW | March 1992 |
| Hodonin | 55 MW | January 1993 |
| Pocerady | 200 MW | January 1994 |
| Ledvice | 110 MW | February 1994 |
| Hodonin | 50 MW | January 1995 |
| Hodonin * | 50 MW | August 1996 |
| Tusimice 1 | 110 MW | September 1996 |
| Hodonin | 50 MW | April 1998 |
| Tusimice 1 ** | 110 MW | April 1998 |
| Ledvice | 200 MW | June 1998 |
| Porici | 55 MW | December 1998 |
| Tusimice 1 ** | 110 MW | December 1998 |
| Tusimice 1 ** | 110 MW | December 1998 |
| Tisova | 50 MW | December 1998 |
| Melnik 2 | 110 MW | December 1998 |
| Melnik 2 | 110 MW | December 1998 |
| Total | 2,020 MW | |
Formerly waste, now re-cycled materials
Roadbed material for roads and railways, refill material replacing coal in exhausted coal seams, landscaping material in recultivation projects, use in dry mortar mixes - these all are the possible ways how to utilise power plant gypsum or the mix of power plant gypsum and ash in some applications.
The production of gypsum plasterboard for the construction of interior walls in residential and other projects and the manufacturing of structural sections are perhaps the best known and most efficient methods of utilisation of desulphurisation products. Knauf Pocerady has been the pioneer in this field, with the joint venture of CEZ and Knauf, Germany, commissioned in full operation in February 1995 in direct neighbourhood of the Pocerady power plant. At about 50% share in the local market and with a smaller part of its output of about 10 million square meters of gypsum plaster boards being exported to some eastern European countries, the Knauf factory has been purchasing virtually the complete output of the power plant gypsum produced by the desulphurisation of five 200-MW units at the Pocerady plant. While the use of power plant gypsum for the production of gypsum plasterboard requires the extraction of limestone, the natural limestone deposits which would have to be extracted otherwise, as the construction industry would hardly do without gypsum plasterboard, are conserved thanks to the technology.
Other projects for the use of power plant gypsum have been under preparation. At the Chvaletice power plant, the use of high-grade power plant gypsum for the production of gypsum and gypsum bricks has been considered and the use of power plant gypsum for the production of gypsum chipboards has been contemplated at the Tusimice power plant. Nevertheless, the main project in the field includes the completion of another gypsum plasterboard factory, this time near the Melnik power plant and by the company Rigips.
Also ash, which formerly used to be flushed to ash dumps, has found new fields of application, such in recultivation of the existing ash dumps or exhausted mines. Mixed with power plant gypsum, ash forms an environmentally safe material allowing the landscape to be formed to bring it to its former shape. The ground so obtained can be re-forested or used to grow fast-growing plants (biomass) for further applications.