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Da bi se dobila kvarcna sirovina koja svojom kvalitetom udovoljava specifičnim zahtjevima pojedinih industrija, rovni pijesak mora proći odgovarajući proces oplemenjivanja. Mogućnost dobivanja koncentrata kvarcnog pijeska odgovarajuće kvalitete ovisi o značajkama rovnog pijeska, u prvom redu o vrsti i sadržaju mineralnih primjesa u pijesku, te značajkama primjenjenih oplemenjivačkih postupaka. Kada se primjese javljaju u obliku oksidnih prevlaka na površini kvarcnih zrna, primjenjuje se atricijsko čišćenje. Odstranjivanjem oksidnih prevlaka, kvaliteta pijeska značajno se može poboljšati. S ciljem utvrđivanja mogućnosti oplemenjivanja kvarcnog pijeska perspektivnih hrvatskih ležišta (“Vrtlinska”, “Štefanac” i “Španovica”) i postizanja koncentrata čija kvaliteta ispunjava zahtjeve domaće industrije, provedena su laboratorijska ispitivanja s tri različita uzorka rovnog pijeska. Ispitivanjima su utvrđene osnovne značajke (granulometrijski, kemijski i mineralni sastav) rovnih uzoraka kvarcnog pijeska, te mogućnost poboljšanja njihove kvalitete primjenom postupaka pranja, klasiranja i mehaničkog atricijskog čišćenja., To meet high quality requirements defined for specific industrial applications, the raw sand often has to be subjected to extensive physical and chemical processing. The possibility of achieving silica sand concentrate of required quality depends mostly on raw sand properties, primarily mineral impurity types and contents, and features of applied beneficiation methods. When the impurities occur in the form of oxide coatings on the surfaces of the single sand grains, attriton scrubbing is applied. By reducing the proportion of oxide coatings on the grains, the quality of sand can be improved. With the aim to determine the possibilities of the beneficiation of silica sand from significant Croatian deposits (“Vrtlinska”, “Štefanac” and “Španovica”) and achieve concentrate grade complying with the requirements of domestic industry, laboratory tests were conducted on three raw sand samples with different SiO2 and impurity contents. Grain size distribution, chemical and mineral composition of raw sand samples, and the possibility of their quality improvement by applying the washing, classification and attrition scrubbing were defined by analysis of test results.

Silica sand is an important non-metallic mineral raw material within the resources of the Republic of Croatia. Croatian silica sand reserves could meet industrial needs over the long term. The 15 exploitation fields are registered, and the average annual production in the last 10 years is about 240, 000 tonnes. Depending on quality i.e. specific physical and chemical properties (grain size distribution, chemical and mineral composition, moisture content, etc.), silica sand is used as the basic mineral raw material for many industrial applications. To meet defined chemical and physical specifications according to intended application, the raw sand often has to be subjected to extensive physical and chemical processing. The paper describes main beneficiation methods used in the processing of sand intended for industrial uses. Beneficiation procedure applied at the silica sand deposit "Jerovec" located in north-western Croatia is presented, as well as the results achieved under field conditions.