This study was aimed to investigate the feasibility to use waste pyrite and sulphuric acid produced from waste pyrite for the reclamation of calcareous sodic soils. The final aim is to displace Na from an exchange complex and replace it with Ca, leading to a decrease in pH and exchangeable sodium percentage (ESP) and an improvement of soil structure. A fertility of the soil may also be enhanced by this technique since waste pyrite can be rich in several micronutrients. An additional advantage to this strategy is that waste pyrite is inexpensive and readily available in large quantities, by contrast to gypsum. In this study, column-leaching tests were carried out to evaluate a change in soil properties upon addition of gypsum and pyritic tailing amendments from a copper concentration plant. An availability of essential micronutrients for a plant growth (Fe, Cu, Zn and Mn) and hazardous potential of pyritic tailings in terms of heavy metal contamination were taken into account. Gypsum, powder waste pyrite and sulfuric acid produced from waste pyrite were applied to the soil with reference to the gypsum requirement (GR) of the soils. The results showed that application of waste pyrite with a dose of 44.74 megagrams per ha was superior to gypsum of 55.20 Mg/ha dose in terms of exchangeable sodium percentage (ESP) in 42 weeks. In addition, application of all the concentrations of sulfuric acid produced from waste pyrite also decreased the ESP values. The best values with sulfuric acid were obtained with a dose of 35.31 Mg/ha in 26 weeks. It was observed that the content of all micronutrients in the soil increased significantly (P<0.01) with waste pyrite and sulfuric acid applications. The levels of the micronutrients after treatments can be classified sufficient for the plant growth except for the iron level with the minimum dose of sulfuric acid application 17 Mg/ha. The heavy metal content in the soil after treatment with the pyritic tailings was found to be lower than the legal limit values. Thus, waste pyrite can be effectively used since rapid amelioration of calcareous sodic soils is possible with no deleterious heavy metal contamination.
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In this study the separation possibility of gangue minerals from a low grade magnetite ore with 45% Fe from an iron ore deposit located near Erzincan-Turkey was investigated. The iron ore deposit consists of mainly magnetite mineral. Hematite is the second iron oxide found in the deposit. The gangue minerals contain mainly SiO2 and Al2O3 impurities. The main object of the research is to investigate the production of a concentrate suitable for iron ore pellet production. The concentrate for pellet production should have at least 65% Fe with reasonable gangue contents (SiO2 < 6.0% and Al2O3 < 1.0%). The Davis tube and low intensity drum type wet magnetic separators were used for upgrading the Fe content and separation of gangue impurities from the iron ore. The results showed that, in order to produce a concentrate with sufficient Fe grade (> 65% Fe), the iron ore should be ground to get 45% of material by weight to be finer than 45 µm. The concentrate with over 65% Fe and 90% Fe recovery could be produced with 45% Fe content from the feed material by crushing, grinding and magnetic separation operations.
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Application of selective flocculation using starch to separate chromite from serpentine has been investigated. It was determined that starch has a specific affinity towards chromite which can be exploited in selective flocculation. However, it was found that this could only be achieved when the amount of serpentine in the chromite-serpentine mixture is below 30% by weight and in the presence of a dispersant such as sodium silicate or ultrasonic treatment of the pulp.
PL
Metoda selektywnej flokulacji z użyciem skrobi jako flokulanta, została użyta do oddzielenia chromitu od serpentynitu. Zostało ustalone, na podstawie badań, że skrobia wykazuje specyficzne powinowactwo do chromitu, który dzięki temu może ulec selektywnej flokulacji. Okazało się jednak, że selektywny rozdział jest możliwy do osiągnięcia w warunkach, gdy ilość serpentynitu w chromicie nie przekracza 30% wagowych. Proces separacji został zrealizowany w obecności dysperganta - krzemianu sodu, a zawiesina była traktowana ultradźwiękami.
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