Building ceramics raw materials
Mineral raw materials used in the industry of building ceramics are varying in age and origin. Raw materials currently exploited for the needs of that industry in Poland come from deposits ranging in age from the Permian to Quaternary. The deposits are distributed practically throughout the whole country. However, they are more common and larger in the south and also their differentiation appears higher than in other parts of the country.
The main building ceramic products are: ceramic bricks and breezeblocks, slates, clinker bricks and ceramic pavements.
Main raw materials used for building ceramics production are clay rocks. Their suitability depends on their plasticity after they are mixed with water. If the plasticity is too high, the mix is corrected by adding such ingredients as sand, crushed brick and fly ash and sawdust. Clay and non-clay raw materials very often occur together - in one deposit.
Raw materials for building ceramics production contain clayey minerals. In loess clayey minerals content is low (couple of %), but in clays it can be 100%. Usually the content is between 40-60%. Other components are quartz sand and dust, feldspars, calcite and dolomite, iron minerals, mica minerals and organic matter.
The most important raw materials of the Quaternary age include stagnant lake sediments such as muds and clays occurring mainly in northern and central Poland as well as loess, glacial tills, alluvial sediments and those of weathering covers and sands. The most important raw materials of the Tertiary age include clays of the so-called Poznań Series from south-western and central Poland and those of the Krakowiec Clays from the area of the Carpathian Foredeep in south-eastern Poland. The Triassic and Jurassic deposits are situated at the margin of the Holy Cross Mts and in the Czestochowa and Opole regions. Building ceramics raw materials deposits in Poland are presented on the map.
According to the Regulation of the Minister of the Environment of the 1st of July 2015 (number of Polish act: Dz. U. 2015, poz. 987) the limit values of the parameters that defines the deposit (Appendix 8 – table 42) are: the maximum documentation depth – to the depth of possible exploitation; the minimum thickness of the deposit – 2 m; the maximum overburden/thickness ratio – 0.5; the maximum content of grains bigger than 2 mm – 1%; the maximum content of ceramic marl with grains diameter bigger than 0.5 mm – 0.4%; the shrinkage in drying - minimum 6%.
The table given below shows reserves and the state of development and exploration of clay raw material for the building ceramics industry.
Anticipated economic resources amounted to 2,037.27 million m3 in 2015 (about 4,074.54 million tonnes) and decreased by 5.80 million m3 (about 11.60 million tonnes – 0.28%).
There were 5 new deposits documented in 2015 (with total resources equal 0.201 million m3 from which 0.129 million m3 are newly-documented): Ołdrzychów I (0.072 million m3) in Dolnośląskie Voivodeship, allocated from Ołdrzychów deposit; 4 other deposits are newly-documented: Chwałowice–Bałdos I (0.020 million m3), Gorzyce–Cetnarski III (0.008 million m3), Otałęż–Głowacki 2 (0.012 million m3) located in Podkarpackie Voivodeship, Lewkowo Stare 3 (0.090 million m3) in Podlaskie Voivodeship.
There were 26 deposits crossed out from “The balance…” with resources partially included within other deposits borders. In Dolnośląskie Voivodeship 10 deposits: Bartek, Bądzów – zarej., Chocianów, Dębno, Gryfów Śląski, Jaśkowice Legnickie, Jelenia Góra (Ceg.), Kamienna Góra, Pawice I i II, Ruszowice – with total resources equal 2.015 million m3; in Łódzkie Voivodeship 2 deposits: Dąbrówka and Klewków II – resources equal 1.386 million m3; in Małopolskie Voivodeship 2 deposits: Gorlice 4 and Ołpiny – resources equal 0.483 million m3; in Mazowieckie Voivodeship 3 deposits: Ciemne I, Góry II and Kobyłka dz.850 – resources equal 0.034 million m3; in Podkarpackie Voivodeship 4 deposits: Chwałowice Maj IV, Dąbrówka Pniowska V, Rożniaty-Piatek IV, Siedleszczany dz.443,444 – resources equal 0.107 million m3; in Podlaskie Voivodeship 2 deposits: Lewkowo Stare II and Lewkowo Stare II/A – resources equal 0.250 million m3 (0.007 million m3 were subsumed into other deposit); in Śląskie Voivodeship 2 deposits: Miedary I and Woźniki Śląskie – resources equal 0.512 million m3; in Świętokrzyskie Voivodeship 1 deposit: Oleśnica 2 – resources equal 21.553 million m3 (all resources have been subsumed into Oleśnica 1 deposit which is under exploitation).
The anticipated economic resources of the deposits crossed out from “The balance…” amounted to 26.330 million m3 and 21.560 million m3 of this sum were subsumed into resources of other deposits in “The balance…”.
Out of the total anticipated economic resources 13.9% are resources within exploited deposits, 70.7% are resources within non-exploited deposits (from that 11.4% within deposits covered by detailed exploration and 59.3% within deposits covered by preliminary exploration) and 15.5% are resources within abandoned deposits.
Out of 1,191 documented deposits of building ceramics clays, 18.3% of deposits are exploited (including 9.7% deposits exploited continuously and 8.6% - exploited temporarily) and 25.8% deposits are non-exploited (including 19.6% deposits covered by detailed exploration and 6.1% - covered by preliminary exploration). The remaining deposits were abandoned (55.9%).
Economic resources within 103 deposits amounted to 157.022 million m3 (about 314.044 million tonnes) that accounts for 54.7% of anticipated economic resources of these deposits. The resources decreased by 8.19 million m3 (5.0%) in comparison with the previous year.
In 2015, production of building ceramics clays was equal 1.667 million m3 (about 3.334 million tonnes) (table 2). It means significant decrease (by 0.286 million m3 – 14.6%) in comparison with the previous year. Traditionally, the biggest production is recorded in: Świętokrzyskie Voivodeship (0.259 million m3 – 15.6% of domestic production), Podkarpackie Voivodeship (0.190 million m3 – 11.4% of domestic production), Dolnośląskie Voivodeship (0.181 million m3 – 10.9% of domestic production), Śląskie Voivodeship (0.171 million m3 – 10.3% of domestic production), Mazowieckie Voivodeship (0.147 million m3 – 8.8% of domestic production). Furthermore, the production amounted to: Pomorskie Voivodeship – 0.120 million m3 – 7.2% of domestic production, Lubelskie Voivodeship – 0.115 million m3 – 6.9% of domestic production, Małopolskie Voivodeship – 0.110 million m3 – 6.6% of domestic production, Opolskie Voivodeship – 0.103 million m3 – 6.2% of domestic production, Wielkopolskie Voivodeship – 0.092 million m3 – 5.5% of domestic production, Kujawsko-Pomorskie Voivodeship – 0.062 million m3 – 3.7% of domestic production, Podlaskie Voivodeship – 0.036 million m3 – 2.2% of domestic production, Lubuskie Voivodeship – 0.035 million m3 – 2.1% of domestic production, Łódzkie Voivodeship – 0.033 million m3 – 2.0% of domestic production, Warmińsko-Mazurskie Voivodeship – 0.010 million m3 – 0.6% of domestic production. The Zachodniopomorskie Voivodeship is the only one without production (since 2012).
There were also 4 changes of deposit names – Legnica-pole Wschodnie (former: Legnica-p.Wschodnie) in Dolnośląskie Voivodeship, Pilzno-Jaworze dolne (former: Pilzno-Jaworze D) in Podkarpackie Voivodeship, Żarki Nr 3 (former: Żarki) in Śląskie Voivodeship and Rostarzewo (former: Rostarzewo I i II) in Wielkopolskie Voivodeship.
The figure given below shows changes in domestic resources and production of clay raw material for building ceramics industry in Poland in the years 1989-2015.
Prepared by: Wojciech Szczygielski
Table 1. Building ceramics raw material - million m3