Slag is a by-product of coal combustion in dry bottom boilers. Slag is separated in a discharge hopper of a brick furnace where it falls into water bath. After the dewatering process it is dispatched to clients.


With its grain-size composition and mechanical properties slag corresponds to slightly clayey and coarse sand. Slag is well workable with vibration metallurgical instruments. CBR firmness meets requirements of the Technical Conditions ”Concept and building construction of surface communications with the aid of fly ashes and ashes” TP 93, published by the Ministry of Transport in 2003 April 3th, and other technical regulations. Slag can be therefore used in the embankments of surface communication formations, backfills of kerfs and sewer conduit, backfill for bridge piers, etc. Low bulk density of slag is very advantageous mainly for construction of embankment bodies on poorly bearing ground. Due to its high shear strength slag can be also advantageously used for backfills of backings.

Slag meets demands of ecotoxicological test results and limit concentrations for the content of harmful substances in dry residue given by the decree no. 294/2005 Coll., and it can therefore be considered as a product harmless from the sanitary point of view within the meaning of the law no. 102/2001 Coll. in force on general safety of construction products. Slag can therefore be used for fills and backfills on the ground surface without limiting the particular location, including the creation of top layers of technical recultivation.

Slag produced in CEZ producing plants is utilizable as a construction product for the following modes of application:

  • Fills of surface communication formations
  • Backfills of backings
  • Backfills for linear structures of underground services (water, sewer and gas conduits)
  • Backfilling material for recultivation of exhausted areas after mineral resources exploitation (surface mines, sand and stone quarries)
  • Surface developments or recultivation of terrains impacted by anthropogenic activity
  • Opening material for production of baked brick products 

References to individual power stations that have valid certificates for slag as a construction product (the extent of the authorized use of slag varies with individual entities, it is, however, possible to state that for the above mentioned modes of application slag from all entities of the CEZ Group can be used). In case of clients´ interest the existing certificates may be extended with other modes of application.



Slag is stored as a waste site.

Loading points:
Sampling point to autosilos – EPR, EPO, EPC, ELE, EDE