Air

 

Air Protection

In 1998, the CEZ, a. s. successfully completed implementation of an air pollutant reduction program, an outline of which may be briefly described in the following:

  • selection of boilers for a reconstruction and an installation of new emission reduction equipment,
  • gradual and permanent decommissioning of boilers not selected for the reconstruction,
  • construction of desulphuring equipment for existing boilers, with an objective to reduce significantly sulphur oxide emissions
  • construction of new fluidized bed boilers, with an objective to reduce significantly gaseous emissions,
  • renewal of precipitators of solid substances polluting the air, with an objective of increasing their efficiency in cases of not decommissioned boilers ("existing" boilers further on) and new fluidized bed boilers,
  • implementation of primary measures in combustion process control (DENOX), with an objective of reducing nitrogen oxide emissions in case of existing boilers,
  • supplementing all coal power plant production units with I&C technology for continuous monitoring of emission quantities,
  • replacement of bunker oil pilot burners for natural gas pilot burners.

Technical specifications of technologies providing for a reduction of air polluting substances correspond with the level of the best technologies available, as recommended by the European Union, and enable the CEZ, a.s. to comply with all the requirements of Czech Republic new legal regulations concerning the atmosphere protection

The production of pollutant emissions released into the air from CEZ Group sources is continually monitored. In 2012, emission limits were complied with at all CEZ Group combustion sources, as was the ČEZ-wide emission sum ceiling along with all other technical conditions for operation relating to air protection, as imposed upon said sources in the operation permits issued by the relevant administrative authorities. In operating coal-fired power plants and power-heating plants, CEZ Group conducts long-term, systematic monitoring of their impact on air pollution through its own in-house network for measuring ground-level concentrations. In 2012, 14 measurement stations were in operation, all located in the vicinity of coal-fired power plants and power-heating plants. The stations measure gaseous pollutants (SO2, NOX) and five of the stations also measure suspended dust particles (PM10, PM2.5). The public is kept informed of the results of emissions and ground-level concentration monitoring conducted in conjunction with the operation of combustion sources through the website, where the results of emissions and ground-level concentration measurements are published, along with figures calculated for individual sources expressing the proportion of the air pollution in their vicinity attributable to them.
All ČEZ, a. s. coal-fired power plants, with the exception of the Dvůr Králové Power-Heating Plant, have implemented continuous measurement of dust, NOX, SO2, and CO2 concentrations.

Orientation survey of principal measures aimed at reducing the emission output of air pollutants

Prunérov power plants (EPR I, EPR II)

  • re-constructing electric separator
  • simplementing a primary measure aimed at reducing the emission output of nitrogen oxides
  • building up desulphurisation unit 

Tusimice power plants (ETU I, ETU II)

  • phasing out ETU I
  • building up a desulphurisation unit in ETU II
  • implementing a primary measure aimed at reducing the emission output of nitrogen oxides in ETU II

Tisová Power Plant

  • building up a desulphurisation unit for one boiler
  • putting 8 boilers out of action
  • building up two new fluid boilers

Melník Power Plant (EME I, EME II)

  • implementing a primary measure aimed at reducing the emission output of nitrogen oxides and carbon monoxide in the combustion products generated by EME II a III
  • building up a desulphurisation unit v EME II a III

Porící Power Plant (including heating plants in Dvur Králové – TDK and in Náchod – TNA)

  • building up two new fluid boilers
  • putting four boilers out of action; the remaining were reconstructed with the aim of making them comply with the prescribed emission limits for nitrogen oxides and for carbon monoxide

Pocerady Power Plant

  • implementing a primary measure aimed at reducing the emission output of nitrogen oxides and carbon monoxide
  • building up a desulphurisation unit
  • putting one boiler unit out of action

Ledvice Power Plant

  • reconstructing electric separators, conditioning generated combustion products
  • building up a new fluid boiler
  • putting one boiler unit out of action

Detmarovice Power Plant

  • implementing a primary measure aimed at reducing the emission output of nitrogen oxides and carbon monoxide
  • building up a desulphurisation unit

Hodonín Power Plant

  • replacing six granulation boilers
  • building up two fluid boilers 

 

Emission limits as determined in the law

Power plant name Heat power input SO2 limit NOx limit CO limit Solid substances limit
Detmarovice 2 180 500 650 250 100
Hodonin 291 1 236 600 250 100
Ledvice 2 610 1 700 650 250 100
Ledvice 3 291 1 236 600 250 100
Melník 2 623 1 200 600 250 100
Melník 3 1374 350 650 250 100
Pocerady 2 831 500 650 250 100
Porici 1 215 1 700 650 250 100
Porici 2 392 832 600 250 100
Prunerov 1 1 233 1 700 650 250 100
Prunerov 2 2 956 500 650 250 100
Tisova K9 292 1 700 650 250 100
Tisova FK11 287 1 252 600 250 100
Tisova FK12 285 1 260 600 250 100
Tusimice 2 2 356 500 650 250 100

 

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.

 

Identification of a coal power plant share at the overall air pollution

The share of particular CEZ coal power plants at the air pollution is evaluated in mathematical models. Even abroad, computation models are routinely used for simulation, of anticipated effects of technical measures at pollution sources on air pollutant quantity changes, and in many cases their use is required.

For an evaluation of a single air pollutant source share at the overall air pollution, a mathematical model is usually the only option available, for a performance of such an analysis. An air pollution computation, in comparison with air pollutant measurements, brings both advantages and disadvantages.

The advantages include the fact, that a computation model may not perfectly describe specifics of a reference point particular location. Additionally, a description of meteorological conditions implemented in such a computation model is a mere generalization, making use of both long-term and short-term information. Consequently, computed average air pollutant concentration values at a specific reference point may often differ from the average air pollutant concentration quantity provided by a measuring station.

The computation model advantages include the fact, that a computed concentration value is a sum of partial concentration values as provided from particular air pollutant sources, which makes possible to identify a share of a particular air pollutant source at the overall air pollution, for a given reference point. Equally, locations and quantity of reference points for the computation may be easily be selected. A collection of such information is significantly less costly, in contrast to the air pollutant measurement itself, where additional problems with its both quality and usability may be encountered.

When the computations are performed each year, however, some of the above mentioned disadvantages change to advantages, because a mutual comparison of computed air pollutant concentration quantities in particular years does not suffer from fluctuations in weather conditions, which in case of a higher occurrence of inversion situations may significantly affect measured concentration quantities.

Into the computation of air pollution in the vicinity of CEZ coal power plants, the following input data were included as the air pollutant sources :

  • all the REZZO 1 monitored sources (in particular, large sources and sources of extensive pollution), located on the whole Czech Republic territory,
  • REZZO 2 sources (medium size pollution sources) and REZZO 3 (local pollution sources), registered in districts within a distance of 60 km from CEZ, a. s. power plants

The air pollution computations were performed for sulphur dioxide, nitrogen dioxide, and airborne dust. The computation itself was performed as follows: in the vicinity of particular CEZ, a.s. power plants, (evaluated area as a square 60 x 60 km, in the centre of which a particular power plant is situated), computation reference points were selected, in a uniform network of 2 x 2 km density. For these 900 reference points, approximately, air pollutant concentration values were computed. From these data, using dedicated topographic software, isolines of equal concentration, i. e. of equal shares at the total air pollution, were created, and then converted into schematic maps of area being evaluated.

A computation of nitrogen oxide air pollution did not include pollution caused by traffic, which in towns, in particular, is quite significant.

The airborne dust concentration computation did not include secondary-dust effects, occurring with higher wind speed causing turbulences of dust settled on the ground. The airborne dust concentration values computed, therefore, display effects of solid substances (particles) brought to the air by sources, which are active and only active during the evaluated period.

Objective determination of the share of CEZ, a.s. coal power plant operation at the air pollution, through model computations, may only be performed if official data are utilized, as included in the "Air Pollutants & Pollution Sources Registry" (REZZO) national system. The mechanism of processing REZZO data and making them available is such, that official current data for each year are available, as a rule, with a year delay (e. g., air pollutant data for the year 2002 would be available not earlier than in the first year-quarter of the year 2004).

On the web page, computed shares of CEZ, a.s. coal power plants are presented, at the total air pollution, provided for particular years of the 1991 to 2001 period (data for dust concentration since 1992). The data are updated annually, towards the end of the second year-quarter. In June 2004, the presentation of shares shall be updated with data processed in computations for the year 2002

 

Summary of key measures aiming to reduce air polluting emissions

Between 1992 and 1999, important measures were implemented in CEZ, a.s. power plants, aiming to ensure operation conditions corresponding with requirements stipulated in the Czech Republic legislation.

In Power Plant Tisova, the following projects were implemented:

  • K 9 (B 6) boiler equipment with new three-section electrostatic precipitators, in the year 1992,
  • K 5, K 6 boilers decommissioned in the year 1992, and subsequently disassembled, 
  • K 4 boiler decommissioned in the year 1993, and subsequently disassembled,
  • 1st fluidized bed boiler (K 11) constructed and introduced into operation, in the year 1996,
  • K 2, K 3 boilers decommissioned in the year 1995, and subsequently disassembled,
  • 2nd fluidized bed boiler (K 12) constructed, and in the year 1998 introduced into operation,
  • K 3, K 4, K 5, and K 6 boiler desulphurization equipment constructed,
  • K 1 boiler decommissioned in the year 1997, and subsequently disassembled,
  • K 7, K 8 boilers decommissioned in the year 1998.

In Power Plant Prunerov 1, the following projects were implemented:

  • K 3, K 4, K 5, and K 6 boiler electrostatic precipitators reconstructed,
  • K 3, K 4, K 5, and K 6 boilers - replacement of burners and combustion space adjustments aiming to reduce nitrogen oxide and carbon oxide emissions (primary measures),
  • K 3, K 4, K 5, and K 6 boiler desulphurization equipment constructed,

In Power Plant Prunerov 2, the following projects were implemented:

  • K 21, K 22, K 23, and K 24 boiler electrostatic precipitators reconstructed,
  • K 21, K 22, K 23 , K 24, and K 25 boilers - replacement of burners and combustion space adjustments aiming to reduce nitrogen oxide and carbon oxide emissions (primary measures),
  • K 21, K 22, K 23, K 24, and K 25 boiler desulphurization equipment constructed,
  • K 25 boiler reconstructed, for a reduction of emissions of nitrogen oxide and solid state contaminating substances,
  • installation of natural gas pilot burners, as a substitution for environmentally unfriendly heavy oil (mazut) burners in K 21, K 22, K 23, K 24, and K 25 boilers.

In Power Plant Tusimice 1, the following projects were implemented: 

  • operation discontinuation of B 6 unit in 1991, B 1 unit in 1992, and B 2 unit in 1993,
  • Power Plant Tusimice I boilers - sealing of electrostatic precipitators and reconstruction of electrostatic precipitator control boxes,
  • Power Plant Tusimice I boilers - APOLLO burnt gas conditioning system introduced, in order to reduce emissions of solid state pollutants,
  • B 3, B 4, and B 5 boiler decommissioning in the year 1998.

In Power Plant Tusimice 2, the following projects were implemented:

  • K 21, K 22, K 23, and K 24 boilers - reconstruction of burnt gas flow distribution in electrostatic precipitators; sealing and optimizing of boiler electrostatic precipitator cleaning systems,
  • K 21, K 22, K 23, and K 24 boilers - substitution of heavy oil (mazut) burners for natural gas burners,
  • K 21, K 22, K 23, and K 24 boilers - desulphurization equipment constructed and put into operation in the year 1997,
  • K 21, K 22, K 23, and K 24 boilers - reconstruction of pulverized fuel burners, modifications of burn-out air burners, and boiler sealing, in order to reduce nitrogen oxide emissions,
  • K 21, K 22, K 23, and K 24 boilers - implementation of measurements of emission output into the desulphurization control system, in the year 1997.

In Power Plant Pocerady, the following projects were implemented: 

  • B 1 unit operation discontinued, in the year 1994,
  • B 2 boiler electrostatic precipitator replaced for a new one, with a guaranteed concentration of solid state pollutants behind the precipitator, of 50 mg.m-3,
  • B 2, B 3, B 4, B 5, and B 6 unit - unit control verification system reconstructed and combustion air control implemented, in order to reduce nitrogen oxide and carbon oxide emissions,
  • B 3, B 5, and B 6 unit boiler electrostatic precipitator replaced
  • B 2, B 3, B 4, B 5, and B 6 unit boiler desulphurization equipment constructed, 
  • B2, B3, and B4 unit boiler modifications, in order to reduce carbon oxide and nitrogen oxide emissions down to 500 mg/m3.

In Power Plant Ledvice, the following projects were implemented: 

  • K 2 and K 3 boilers - electrostatic precipitators reconstructed, (mechanical separators replaced by the electrostatic precipitators, meeting the demands of the Act no. 309 / 1991 Coll., applicable to emission limitations for new (energy) sources),
  • K 1 boiler - implementation of Apollo burnt gas conditioning system, in order to reduce concentration values of solid state pollutants,
  • B 1 unit - attainable power output reduced from 200 MW to 185 MW, in the year 1996,
  • K 2 and K 3 boilers - desulphurization equipment constructed and put into operation in the year 1996, 
  • K 1 boiler operation discontinued in December 1998; a fluidized bed boiler constructed at the location of the disassembled K 4 boiler, and introduced into operation in the year 1998.

In Power Plant Melnik 2, the following projects were implemented:

  • K 9 and K 10 boilers - measures implemented, in order to reduce nitrogen oxide and carbon oxide contents in boiler burnt gas,
  • K 9 and K 10 boilers - desulphurization equipment constructed, 
  • K 7 and K 8 boilers disassembly preparation, in the year 1999.

In Power Plant Melnik 3, the following projects were implemented:

  • K 11 boiler - electrostatic precipitator power supply control boxes replacement
  • K 11 boiler - measures implemented, in order to reduce nitrogen oxide and carbon oxide contents in boiler burnt gas, 
  • Desulphurization equipment for K11 boiler constructed.

In Power Plant Porici, the following projects were implemented: 

  • K 3 and K 4 boilers - semi-pulse electrostatic precipitator power supply installed,
  • FK 7 atmospheric fluidized bed boiler constructed (1994 -- 1996),
  • K 5 and K 6 boilers removed, and  FK 8 fluidized bed boiler constructed in their location, instead,
  • K 1 and K 2 boilers - APOLLO burnt gas conditioning system introduced, in order to reduce solid state pollutants and nitrogen oxide emissions,
  • K 3 and K 4 boiler reconstruction implemented in the year 1997, in order to achieve required emission limitations applicable to nitrogen oxide and carbon oxide quantities,
  • K 1 and K 2 boiler operation discontinued towards the end of 1998.

In Heat Plant Nachod, the following projects were implemented: 

  • K 4 boiler - cloth filter and dual fuel burners (natural gas auxiliary heating) installed,
  • K 5 and K 6 equipped with dual fuel burners (heating oil and natural gas),
  • K 12 boiler converted to natural gas.

In Heat Plant Dvur Kralove, the following projects were implemented: 

  • K 3 boiler - cloth filter installed,
  • K 1 and K 2 boilers reconstructed, including natural gas branch line construction.

In Power Plant Detmarovice, the following projects were implemented: 

  • K 1, K 2, K 3, and K 4 boilers - primary measures adopted, in order to reduce nitrogen oxide and carbon oxide emission quantities
  • desulphurization equipment for all the power plant boilers constructed.

In Power Plant Hodonin, the following projects were implemented: 

  • replacement of six dry bottom boilers with two fluidized bed boilers, each having 170 t/hour power output rate (lignite fuel),
  • 13 MWt emergency boiler introduced into operation in the year 1998 (light fuel oil).

 

CEZ Air Pollutant Measurements

The stable measurement network of the Czech Republic National Air Pollution Monitoring, i.e. the air pollutant measurement network of hygiene stations, focuses mostly on coverage of population settlements. The measurements are made, in particular, in order to identify polluted air effects on population health, as a summation of all emission source effects, contributing to the air pollution.

The CEZ, a.s. air pollutant measurements are based on the need to collect information concerning company operation effects on the ambient environment. The air pollutant measuring stations, operated by CEZ electricity utility, are, therefore, ad-hoc stations, located in a manner allowing for measurements of air pollution caused by coal power plants, and minimizing effects of other pollution sources, such as local heating, in particular.

Results from CEZ, a.s. air pollutant measuring stations are continuously submitted, in monthly intervals, to the national Air Quality Information System (managed by CHMU) and further utilized within the CEZ company, for an assessment of its contribution to the air pollution of its operation area.

Measures, aiming to reduce air pollutant quantity, adopted by CEZ, a .s. in its coal power plants, significantly reflected, apart from others, in air pollutant quantity measurements. Such facts are supported, in addition, by the data presented on other pages of the web site, under the "Environment / Atmosphere / Emissions" section“. The pages provide information concerning air pollutant values measured at stations operated by the CEZ electrical utility, since 1996. The information includes annual, monthly, and daily average values of measured air pollutants, together with their 30 minute and hourly values. The data are presented as verified, and therefore are only updated after the process completion, i. e. in two weeks intervals.

 

Measurements of atmospheric emissions from CEZ, a.s. coal power plants

Monitoring of air polluting substances released from coal power plants is permanently ensured.

Four primary pollutants, subjected to emission limits, are measured continuously. These are emissions of sulphur oxide, nitrogen oxide, carbon oxide, and solid state substances. Since 1996, additionally, continuous evaluation of emission limit compliance has been ensured, in all coal power plants under operation. Pollutant concentration values are processed for 30 minute, daily, and annual intervals, with emission quantity calculations performed from measured concentration values on a monthly basis.

Emission measurement results are utilized, additionally, for an identification of coal power plants effects in the air pollution.

Technology measures, adopted in coal power plants in the period 1996 – 1998, were substantially reflected in a reduction of emission quantities released to the air. Such facts are supported, in addition, by the data presented on other pages of the site, under the "Environment / Atmosphere / Emissions" section. There is information available, concerning emission quantities since the year 1991. Both annual and monthly values are available. The data are presented as verified, and are updated after the process completion, i. e. in monthly intervals, with a two week delay.