The paper discusses the issue of the utilization of selected raw materials obtained as by-products of rock mining and processing in the ceramic industry in Poland. The raw materials in question are: kaolinite-rich clayey substance remaining after quartz sand washing and alkalis-rich finest fractions generated in the course of the production of granite crushed aggregates. Despite usually high content of coloring oxides, they have been utilized for the production of ceramic goods, the high whiteness of which is not required after firing. High interest in these materials was connected with the implementation of the fast firing method as well as modernization and large scale expansion of the domestic ceramic industry, especially ceramic tiles and sanitaryware sectors. Between the mid-1990s and 2018, the annual consumption of kaolinite raw materials being by-products of quartz sand washing increased from ca. 20,000 to 100,000–120,000 Mg. At the same time the sales of secondary granite fractions utilized as a flux in the ceramic industry rose from 30,000 to 120,000 Mg per year in 2007–2008, and 50,000–70,000 Mg per year most recently. The development of the utilization of these raw materials has been an example of the rational and comprehensive management of all the minerals that occur in deposits in operation. This is particularly important in the context of the depletion of these raw materials reserves and the limited availability of their new deposits. Furthermore, this also makes a contribution towards reducing the scale of imports of raw materials for the ceramic tile industry, which is inevitable due to insufficient supplies from domestic sources.
The aim of this study was to examine the pollution level of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and selected chloroorganic pesticides (HCH isomers, DDT and its metabolites, aldrin, dieldrin, endrin, heptachlor, endosulfan I and II, and methoxychlor) in surface sediments from selected fjords, tidal plains and lakes from the North Svalbard area. The sediments were collected from 34 sampling stations in July 2005. Only endosulfan I and methoxychlor, among selected chloroorganic pesticides, were measured in concentrations near detection limit (LoD) in fourteen sediment samples. The sum of seven PCB congeners varied from < 0.9 to 5.6 ng g-1 d.w. in sediments from fjords and tidal plains and from < 0.1 to 14.6 ng g-1 d.w. in sediments from lakes. The concentrations of analysed PAH compounds in surface sediments from lakes were over ten times higher (Ʃ16PAHs to 429 ng g-1 d.w.) than in sediments from fjords and tidal plains (Ʃ16PAHs to 36 ng g-1 d.w.).
The aim of this paper is to present an assessment of the slip influence on the deflection of the steel plate-concrete composite beams, which are a new type of a design concept. The proposed method is based on the procedure included in the PN-EN 1992-1-1, which has been modified with taking into consideration interface slip. The theoretical analysis was verified by experimental studies.