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In this study, we examine an innovative approach to determining the Bond work index, a key parameter in the mining and cement production industry that indicates material grindability. The method relies on the first-order kinetics law and allows for the estimation of approximate index values with any number of grinding cycles, depending on the desired data accuracy. An important aspect of this approach is the multiplication of parameters G and P80 for each cycle by specific coefficients, achieving values close to those of the last grinding cycle when equilibrium is reached in the standard test. In this paper, we compare the results obtained by the innovative method with the standard Bond procedure on various samples of mineral materials. Our analysis shows a significant reduction in the mean square error as the number of grinding cycles increases, indicating increased precision of the new approach

Soil amendments and conditioners are indeed crucial for maintaining soil health and fertility, especially in the face of a growing global population. These tools help to create an environment where fertilizers can effectively provide essential nutrients to crops. As soils become increasingly depleted worldwide, it is essential to focus on improving soil health through the use of these amendments and conditioners. This will support the production of nutrient-rich crops and also contribute to sustainable agriculture practices that can feed a growing population. This paper, provide an overview of their purpose, how they function, and how soil conditioners are generally obtained.

U ovom radu je prikazan deo tehnoloških ispitivanja, koncentracije rovne bentonitske rude iz ležišta „Bijelo Polje“-Bar koja su u ITNMS-u obavljena na 3 uzorka. Posle određivanja granulometrijskog i mineraloškog sastava polaznih uzoraka bentonita, ispitivana je mogućnost njihove koncentracije primenom postupaka mokrog klasiranja, Postupcima mokrog klasiranja dobijene su dve vrste koncentrata klase krupnoće -0,075+0,00mm I 0,037+0,00mm za sva tri ispitivana uzorka. Dobijeni koncentrati su ispitivani rendgenskom difrakcionom analizom da bi se utvrdio njihov mineralni sastav, i laserskom difrakcionom analizom radi utvrđivanja njihovog granulometrijskog sastava. Na osnovu dobijenih rezultata obavljenih analiza vršena je validacija dobijenih koncentrata bentonita i samog postupka mokrog klasiranja.

Smelting used to be less efficient; therefore, wastes obtained from historical processing at smelter plants usually contain certain quantities of valuable metals. Upon the extraction of useful metal elements, metallurgical slag can be repurposed as an alternative mineral raw material in the building sector. A case study was conducted, which included an investigation of the physico-chemical, mineralogical, and microstructural properties of Pb–Zn slag found at the historic landfill near the Topilnica Veles smelter in North Macedonia. The slag was sampled using drill holes. The mineralogical and microstructural analysis revealed that Pb–Zn slag is a very complex and inhomogeneous alternative raw material with utilizable levels of metals, specifically Pb (2.3 wt.%), Zn (7.1 wt.%), and Ag (27.5 ppm). Crystalline mineral phases of wurtzite, sphalerite, galena, cerussite, akermanite, wüstite, monticellite, franklinite, and zincite were identified in the analyzed samples. The slag’s matrix consisted of alumino-silicates, amorphous silicates, and mixtures of spinel and silicates. Due to the economic potential of Pb, Zn, and Ag extraction, the first stage of reutilization will be to transform metal concentrates into their collective concentrate, from which the maximum amount of these crucial components can be extracted. This procedure will include combination of gravity concentration and separation techniques. The next step is to assess the Pb–Zn slag’s potential applications in civil engineering, based on its mineralogical and physico-mechanical properties. Alumino-silicates present in Pb–Zn slag, which contain high concentrations of SiO2, Al2O3, CaO, and Fe2O3, are suitable for use in cementitious building composites. The goal of this research is to suggest a solution by which to close the circle of slag’s reutilization in terms of zero waste principles. It is therefore critical to thoroughly investigate the material, the established methods and preparation processes, and t

This paper presents results of investigations of the possibility of using “Glavatske Kuće”-Kotor limestone (Republic Montenegro) as filler in various industry branches. Micronization methods, granulometric composition, oil and water absorption and degree of whiteness were investigated, and chemical and thermal analyses (DT/TG) were performed. Physico-chemical properties of this limestone classify it among high quality carbonate raw materials with high CaCO3 content of 97,68%, as well as MgO content of 0,884% and low silicate content (SiO2 0,240%). The quality of this limestone meets the requirements of the standards for the use of calcium carbonate as a filler in the following industries: paints and coatings; glass, foundry, and sugar industry as well as metallurgy. Due to the low degree of whiteness (77,85%), limestone "Glavatska kuće" cannot be used in the paper and cosmetic-pharmaceutical industry. The high content of Cd is also unacceptable for the cosmetic-pharmaceutical industry. Due to the high content of Cu, this limestone cannot be used in the production of rubber and PVC. Due to the increased content of MgO, this limestone cannot be used in the production of mineral fertilizers. Due to the relatively high content of biogenic elements MgO, P2O5, K2O, Cu, and heavy metals Ni and Cd, limestone Glavatske Kuće”-Kotor cannot be used, in production of cattle feed and for neutralization of acidic soils.

U radu su prikazani rezultati istraživanja iz oblasti usitnjavanja, sakupljani duži niz godina, u Institutu za tehnologiju nuklearnih I drugih mineralnih sirovina. Poznato je da se područja sa frekfencijama preko 3•1011 do 3•1014 Hz nalaze u elektromagnetnom spektru infracrvenog i daleko infracrvenog emitovanog ili apsorbovanog zračenja. U radu su prikazani rezultati kada se materijal i kugle u mlinu nalaze na jednoj od pomenutih frekfencija, što nam omogućava da pomoću Borovog uslova frekfencija pristupimo izračunavanju emitovanih i apsorbovanih molarnih energija. Polimorfne promene materije pri usitnjavanju su promene izazvane fizičkim procesima, odnosno emitovanjem određene količine energije od strane mlina I adsorbovanjem tih energija od strane materijala. Izvršen je pokušaj da se odrede nivoi tih energija. Prikazani rezultati pokazuju da sve jedinke u mlinu pretrpe lokalni pritisak i tada na njima, delimično ili u celini, dolazi do polimorfnih promena materije menjajući fazna stanja i kristalnu strukturu iste. Na zrnima minerala na veoma ograničenim mestima po površini (10-3 do 10-5 cm2) i u kratkim vremenskim periodima trajanja (10-4 s) dolazi do povećanja temperature čak do 1000 C što su autori iz reference [3] nazvali magma plazma modelom slika 1. Rad prikazuje praćenje polimorfnih promena materija preko promena njihovih termodinamičkih veličina. Takođe, postoje i velike razlike polimorfnih promena minerala u zavisnosti od mineraloškog oblika u kojem se materija nalazi.

Boron is a rare element from the group of non-metals and it occurs in nature in over 250 boron-bearing minerals-borates. Turkey has the largest borate reserves and is their largest producer. Serbia has significant borate resources, for now without exploitation and processing. This paper presents the results of investigating two borate samples from the deposit ""Pobrđe. The following properties were determined on borate samples: free and hygroscopic moisture, granulometric composition, chemical composition, mineralogical analysis by size classes, and XRD analysis.

Velike količine flotacijske jalovine stvaraju se u Srbiji (preko 20 Mt), kao i u svetu (20.000-25.000 Mt). Zbog zaostalih teških metala (Pb, Cu, Fe i Zn...) ona predstavlja potencijalno opasni otpad koji bi trebalo zbog vrednosti plemenitih i obojenih metala u njoj reciklirati. Na Rudniku „Rudnik“ svake godine se generiše oko 250.000 t, flotacijske jalovine, od 1953. god. oko 11 Mt. Naučno istraživačkim radom i obavljenim ispitivanjima u okviru Projekta-REASONING (2024.-2026.) dobiće se rezultati i osvojiće se nova inovativna rešenja i znanja čija će implementacija omogućiti osvajanje tehnoloških postupaka reciklaže i prerade flotacijske jalovine Rudnika “Rudnik”.

Biochar continues to strengthen its presence in many new industries with its new applications, which are full of scientific and business news. A flurry of activity has sprung up around this carbon-based material, produced from biomass, following its use in water treatment, energy production and animal husbandry. In any new industry, process and product development, as well as feasibility studies, are very important for the product to come to market. This is especially true when it comes to biochar. Besides being in its infancy as an industry, biochar itself presents a number of challenges that make various tests necessary. Many properties affect the quality and performance of biochar products (pore size, cation exchange, electro- conductivity...) and will most likely vary depending on the starting material and the method of obtaining. Biochar can be made from a very long list of biomass materials. Although the above creates opportunities for industries that abound with highly adaptable products, it can still make biochar unpredictable, given that each starting material affects the characteristics of the final products differently.

U ovom radu je prikazan deo tehnoloških ispitivanja koja su u ITNMS-u obavljena na 5 vrsta uzoraka (3 rovna i dva kompozita) bentonita iz ležišta „Bijelo polje “- Opština Bar. Bentonit iz ležišta „Bijelo Polje“-Bar je Ca-bentonit, i u okviru tehnoloških ispitivanja definisani su I utvrđivani uslovi njegove aktivacije i prevođenja u alkalno aktivirani Na-oblik. U radu su takođe prikazani ispitivanja mogućnosti primene neaktiviranih i aktiviranih uzoraka bentonita u livnicama. Tehnološka ispitivanja mogućnosti primene bentonita „Bijelo Polje“ – Bar u metalurgiji su obavljena u Laboratoriji za kontrolu kvaliteta sirovina i finalnih proizvoda fabrike bentonita TD ,, BENTOMAK,, - Kriva Palanka – Ginovci (S. Makedonija). Parametri kvaliteta odredjeni su saglasno postojećim ISO, ASTM, EN kao i ex-Yu standardu JUS B.F1.040 koji se odnosi na bentonite za izradu kalupa i jezgara za livenje svih vrsta odlivaka.

This paper describes a part of the experimental procedure for testing the performance of grinding media (steel balls) during the smelting slag milling, as well as the modeling procedure and model results that predict the consumption of balls under given experimental conditions. Firstly, the most suitable mineral raw material for testing the durability of the grinding media was defined. In laboratory conditions, it was determined that it is most expedient to use slag from the melting process of Pb-Zn concentrate for testing. The coarse moisture content was determined on the initial slag sample, while the particle size composition and Bond work index were determined on the crushed slag samples. In accordance with the characteristics of the raw material, the technical-technological parameters of the system for wet grinding of slag were defined, in which the balls durability test was performed. The obtained results showed that the consumption of grinding media is about 1 kg/t of slag. Six ANN models, developed on the basis of experimental results, showed good predictive abilities when it comes to stel balls consumption. As a result of modeling, high correlation coefficients were obtained, the value of which was about R = 0.99.

Potassium and ammonium salts are necessary to meet the nutritional needs of crops. While the granulation of these materials has traditionally been done by roller compaction, the demand for a rounder and less angular product has led some fertilizer manufacturers to introduce an additional production line to their operations: pelletization (wet granulation) with a disc pelletizer. This paper presents possible alternatives in the production process of potassium and ammonium sulfate fertilizers, provided by the pelletization process.

This paper presents results of investigations of the possibility of using “Glavatske Kuće”-Kotor limestone (Montenegro) as filler in various industry branches. Micronization methods, granulometric composition, oil and water absorption and degree of whiteness were investigated, and chemical and thermal analyses (DT/TG) were performed. Physico-chemical properties of this limestone classify it among high quality carbonate raw materials with relatively high CaCO3 content of 97.68 %, as well as low MgCO3 content of 1.849 % and low silicate content (SiO2 0.24 %). Its quality satisfies requirements of standards on using of calcium carbonate as filler in industry of paints and coatings; glass industry; foundry industry; sugar industry and metallurgy. Due to the low degree of whiteness (77,85 %) “Glavatske Kuće” limestone cannot be used in pharmaceutical and cosmetics industry, paper industry. Because of increased MgO content, limestone “Glavatske kuće” cannot be used in the fertilizers industry. Due to relatively high content of heavy metals, Cu (47 ppm), Ni (50 ppm) and Cd (8 ppm), as well as biogenic elements P2O5 (0.0234 %), K2O (0,0157 %), “Glavatske Kuće” limestone cannot be used in production of cattle feed and for neutralization of acidic soils.

Powdered gypsum products were the standard for agricultural gypsum for many years, but as growers look to maximize their return on investment, they are increasingly turning toward pelletized gypsum – a premium alternative. Pelletized gypsum offers several significant advantages over other forms of gypsum such as powdered or ultra-fine gypsum, these advantages will be discussed in the paper. This has led to increased grower adoption and a greater demand for fertilizer and soil amendment producers to offer gypsum in a pelletized form. Producers are also finding that they stand to gain a few benefits from offering a pelletized product as well.

Limestone is a versatile commodity used to create products for ag-ricultural, environmental, and industrial purposes. Cement, paint, soil amend-ments, and even breakfast cereals all contain this resourceful mineral. Of course, mined limestone is not naturally found in a suitable form for many of these products. Therefore, various processing systems are needed to transform raw limestone rock material into a useful product. Common limestone processing methods that prepare the material for subsequent manufacturing stages include drying, calcining, pre-conditioning, and pelletization. The following information highlights limestone processing issues associated with these techniques, as well as general material challenges associated with limestone manufacturing.

Pb-Zn slag from “Topionica”-Veles- North Macedonia, belongs to potentially valuable technogenic raw materials. There are over 2,000,000 tons of this material at the landfill near Topionica-Veles. In ITNMS, a detailed physic-chemical characterization was performed on this sample of Pb-Zn slag. These tests were the basis for the validation of this raw material and they determined the parameters that are needed as a basis for further technological tests.

Pelletizing, not to be confused with pelleting (extrusion), continues to see increasing use across industries for the many benefits it can offer to previously difficult-to-handle bulk solids and fines. Here’s an inside look at the principles behind this process, the equipment used, and the many benefits producers can gain from pelletizing their material.

This paper presents the results of testing the possibility of using limestone from the „Međeđe“ - Nikšić deposit in different industries. During the examination, the coarse moisture, chemical composition, granulometric composition, bulk and particle density, degree of whiteness, oil and water absorption, granulometric composition of micronized samples and specific surface area were determined. All tests were performed on 8 samples taken from different parts of the deposit and the mean values of the obtained results are presented here. Based on the physico-chemical characteristics, it can be stated that this limestone has a high content of CaO and CaCO3 of 99.01%, as well as a relatively low content of MgO of 0.32% and a low content of SiO2 of 0.26% and alkali and R2O3, with also low content of heavy metals, which is very favorable for limestone. With these physico-chemical properties, this limestone can be used in the following industries: paints and varnishes, paper, rubber and PVC, foundry and foundry industry, sugar industry, metallurgical purposes, glass production, animal feed production and mineral fertilizer production. A serious defect of „Međeđa“ limestone is the low degree of whiteness, which does not exceed 89.6%, which prevents its use in the pharmaceutical and chemical industries, while the relatively high content of K2O, Fe and Mn prevents its use in calcification of acid soils.

Smelting slag from "Topionica" -Veles (Northern Macedonia) owned by the company "KEPS MONT GROUP" Skopje is a potentially valuable raw material. Tests have shown that this is an inhomogeneous raw material with significant contents of non-ferrous metals, primarily Pb, Zn, Cu, and silver is present from precious metals. Mineralogical tests have shown that the composition of man-made raw materials is very complex and consists of amorphous and mineral phases, ie the microscopic method showed the following composition: amorphous phase, lead alloys, zinc alloys, vistite (FeO), sphalerite, galena, cerusite, elemental silver, elemental copper, elemental iron, magnetite, spinel, rutile, hematite, troilite (FeS). The most common amorphous phase (glass matrix) of spinel, silicate and mixed (spinel-silicate) composition is in the sample, while vistite, which occurs in the form of skeletal separations in the glass matrix, is significantly less represented. Based on SEM analysis (scanning electron microscopy), these are Fe-Mn-Zn spinels. Lead and zinc alloys are the most common. Mineralogical analysis by size classes determined that useful and unuseful components of Pb-Zn slag "Veles" were released at a fineness of -0.1 + 0.00 mm, so that magnetic separation tests were performed on this size class. Magnetic separation was performed on two devices, a Davis wet analyzer and a dry disk magnetic separator. By magnetic separation on a Davis magnetic separator, a small degree of iron concentration in the MF (1,134) relative to the input was obtained, with low iron distribution in the magnetic fraction of 16.79%. Magnetic separation on a dry disk magnetic separator also yielded a low degree of iron concentration in the magnetic fraction with distribution of 55.38% and 44.62% in the non-magnetic fraction.

This paper presents results of investigations of the possibility of us-ing “Vučića Brijeg”-Ulcinj limestone (Republic Montenegro) as filler in vari-ous industry branches. Micronization methods, granulometric composition, oil and water absorption and degree of whiteness were investigated, and chemical and thermal analyses (DT/TG) were performed. Physico-chemical properties of this limestone classify it among high quality car-bonate raw materials with high CaCO3 content of 97.87%, as well as MgO con-tent of 1.04% (2,18% content of MgCO3 ) and low silicate content (SiO2 0.40%). Its quality satisfies requirements of standards on using of calcium carbonate as filler in industry of paints and coatings; paper industry; rubber and PVC industry; glass industry; production of mineral fertilizers; foundry industry; sugar industry and metallurgy. Due to the low degree of whiteness (81.65%) „Vučića Brijeg” limestone cannot be used in pharmaceutical and cosmetics industry. Due to rela- tively high content of heavy metals, Pb (55 ppm), Cu (10 ppm), Ni (23ppm) and Cd (5 ppm), “Vučića Brijeg”-Ulcinj limestone cannot be used, in production of cattle feed and for neutralization of acidic soils.

This paper presents the results of experiments performed to determine how the quantity of the binder (bentonite) and the parameters of the laboratory roll press affect the quality of the briquettes obtained from limestone powder. These experiments aim to examine the conditions in which limestone briquettes are formed and to determine their use for agricultural purposes. During the experiments various mass fractions of bentonite was added to limestone (from 1 to 10 %), while the force of roll press drums ranged from 2 to 25 kN. The briquettes have been tested by applying scanning electron microscopy (SEM), differential thermal and thermo-gravimetric (DTA/TG) analyses, X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). Bentonite distribution was found to be uniform within the compact briquette structure. Formation of new compounds was not evidenced. The experiments also demonstrated that during briquetting, limestone properties remain unchanged, the changes are only physical, water solubility is not reduced, mechanical properties (impact resistance, compressive strength and abrasion resistance) are satisfactory by the transport and storage terms if the binder mass fraction is over 5% and the briquetting force exceeds 10kN and finally there is no loss due to wind dispersal during application. The only downside of the "green" briquettes obtained is the time required for their complete disintegration if totally immersed in water.

U ovom radu su prikazani rezultati ispitivanja mogućnosti primene krečnjaka iz ležišta Međeđe-Nikšić u različitim granama industrije. Prilikom ispitivanja krečnjaka određena je vlaga, hemijski sastav, granulometrijski sastav, nasipna masa, specifična zapreminska masa, stepen beline, upijanje ulja i vode, granulometrijski sastav mikronizovanih uzoraka i specifična površina. Sva ispitivanja su obavljena na 8 uzoraka uzetih iz različitih delova ležišta a u radu su prikazane srednje vrednosti dobijenih rezultata. Na osnovu fizičko-hemijskih karakteristika može se konstatovati da krečnjak iz ovog ležišta ima visok sadržaj CaO i CaCO3 od 99,01%, relativno nizak sadržaj MgO od 0,32%, nizak sadržaj SiO2 od 0,26%, alkalija i R2O3, kao i nizak sadržaj teških metala, što je veoma povoljno za primenu krečnjak. Sa ovim fizičko-hemijskim karakteristikama, ispitivani krečnjak se može koristiti u sledećim granama industrije: boja i lakova, papira, guma i PVC, livarstvo i livnička industrija, industrija šećera, metalurgija, proizvodnja stakla, proizvodnja stočne hrane i proizvodnja mineralnih đubriva. Ozbiljna mana krečnjaka iz ležišta Međeđe je nizak stepen beline, koji ne prelazi 89,6%, što onemogućava njegovu upotrebu u farmaceutskoj i hemijskoj industriji, dok relativno visok sadržaj K2O, Fe i Mn sprečava njegovu primenu za kalcifikaciju kiselih zemljišta., This paper presents the results of testing the possibility of using limestone from the "Međeđe" - Nikšić deposit in different industries. During the examination, the coarse moisture, chemical composition, granulometric composition, bulk and particle density, degree of whiteness, oil and water absorption, granulometric composition of micronized samples and specific surface area were determined. All tests were performed on 8 samples taken from different parts of the deposit and the mean values of the obtained results are presented here. Based on the physico-chemical characteristics, it can be stated that this limestone has a high content of CaO and CaCO3 of 99.01%, as well as a relatively low content of MgO of 0.32% and a low content of SiO2 of 0.26% and alkali and R2O3, with also low content of heavy metals, which is very favorable for limestone. With these physico-chemical properties, this limestone can be used in the following industries: paints and varnishes, paper, rubber and PVC, foundry and foundry industry, sugar industry, metallurgical purposes, glass production, animal feed production and mineral fertilizer production. A serious defect of "Međeđa" limestone is the low degree of whiteness, which does not exceed 89.6%, which prevents its use in the pharmaceutical and chemical industries, while the relatively high content of K2O, Fe and Mn prevents its use in calcification of acid soils.

This paper presents the results of physico-chemical characterization of both the initial samples of lithotamnian limestone and seaweed (Ascophyllum Nodosum), and the products of aggregation of their mixtures in different ratios by the pelletization process. The initial samples were waste limestone from filter plants and dried seaweed. The final product of the pelletization process should serve the needs of agriculture as a means of biostimulation and can also be used in raising the pH levels of acidic soils. Several different pellet formulations were obtained by the process of discontinuous pelletization, and also by using a simulation of the continuous pelletization process on a pelletization plate. Tests of the mechanical properties of the pellets showed that the best results are shown by the pellets of the 4K sample, which were obtained by a continuous pelletization process with a mutual ratio of seaweed and limestone of 70:30%.

This paper presents results of investigations of the possibility of using “Pješivački Do”-Danilovgradlimestone as filler in various industry branches. Micronization methods, granulometric composition, oil and water absorption and degree of whiteness were investigated, and chemical and thermal analyses (DT/TG) were performed.Physico- chemical properties of this limestone classify it among high quality carbonate raw materials with high CaCO3 content of 98.65%, as well as low MgCO3 content of 0.95% and low silicate content (SiO2 0.23%). Its quality satisfies requirements of standards on using of calcium carbonate as filler in industry of paints and coatings; paper industry; rubber and PVC industry; in production of cattle feed; glass industry; production of mineral fertilizers and sugar industry. Due to the low degree of whiteness (87,6%) Pješivački Do”limestone cannot be used in pharmaceutical and cosmetics industry. Due to relatively high content of Cr (10 ppm) as heavy metal, content of S (0,19%), as well as biogenic elements P2O5 (0.030%), “Pješivački Do” limestone cannot be used in, foundry industry and metallurgy and for neutralization of acidic soils.

U ovom radu predstavljeni su rezultati fizičko-hemijske karakterizacije kako polaznih uzoraka litotamnijskog krečnjaka i morske alge (ascofyllum nodosum), tako i proizvoda okrupnjavanja njihovih mešavina u različitim odnosima postupkom peletizacije. Polazne uzorke su predstavljali otpadni krečnjak iz filterskih postrojenja, kao i sušena morka alga. Krajnji proizvod okrupnjavanja postupkom peletizacije treba da služi za potrebe poljoprivrede, kao sredstvo za biostimulaciju I ujedno sredstvo za podizanje pH kiselih zemljišta. Dobijeno je nekoliko različitih formulacija peleta postupkom diskontinualne peletizacije, kao i simulacijom kontinualnog procesa peltizacije na peletizacionom tanjiru. Ispitivanja mehaničkih osobina peleta su pokazala da najbolje rezultate pokazuju peleti uzorka 4K, koji su dobijeni kontinualnim postupkom peletizacije sa međusobnim odnosom morske alge i krečnjaka 70:30%.

Industrial wastewater contains recalcitrant organic compounds with a very complex chemical structure, built of molecules with long chains of carbon atoms and attached different functional groups. Chemical or biological treatments used for removal of these compounds are being replaced with more efficient non-commercial wastewater treatments. Advanced oxidation processes overcome limitations of conventional methods regarding formation of by-products during degradation of recalcitrant organic compounds. The Fenton process, or use of the Fenton's reagent, has became one of the most utilized processes due to simplicity, economy and accessible amounts of ferrous iron and hydrogen-peroxide, which are used in the process. In specific, the Fenton's reagent is a catalytic-oxidative mixture of these two components. The ferrous iron Fe2+ initiates and catalyzes decomposition of H2O2, resulting in generation of hydroxyl radicals, which are the main radical species in the process able to detoxify several organic pollutants by oxidation. In addition, other mechanisms besides formation of hydroxyl radicals may occur during the Fenton process and participate in degradation of target pollutants. Generally, the treatment efficiency relies upon the physical and chemical properties of target pollutants and the process operating conditions. The main disadvantage of the Fenton process is production of sludge formed by iron hydroxide at certain pH values. An alternative solution for this problem is application of this process in fluidized bed reactors. This paper presents an overview of Fenton and photo-Fenton processes in dispersed systems for removal of different industrial wastewater pollutants. The most important process parameters, required for efficient degradation of recalcitrant organic compounds are also described, such as the catalyst type, pH value, temperature, H2O2 concentration and retention time. Strict control of Fenton process parameters in fluidized bed reactors at desire

The part of the results, obtained during the technological investigations of the ore from the deposit ’’Cerovo-C2’’ deposit - Cementation zone, are presented in this paper. Investigations were undertaken at different flotation conditions (three collectors and grinding fineness) in order to define possibility and optimal conditions for processing the ore from this deposit. Obtained results indicate the possibility for producing the copper concentrate with the commercial quality. Best results were obtained with the collector Flomin C4132 and grinding fineness of 80 % below 0.074 mm, where the copper content in the rough concentrate was 4.64 % and the copper recovery was 81.74 %.

This study shows the results of flotation concentration of mica minerals from kaolinised granite taken from the "Basica bare" deposit - Kobas, Srbac, The Republic of Srpska (B&H). Mineralogical composition of kaolinised granite is as follows: kaolinite, feldspar, quartz, and mica. After separating >0.630 mm, and LT 0.043 mm size class where kaolinite is concentrated, the rest is -0.630+0.043 mm class containing quartz, feldspar and mica. The mica concentrate was obtained by the flotation concentration, while feldspar and quartz were in the flotation underflow. According to the mineralogical analysis, the most abundant minerals are mica and chlorite/clays, while quartz and feldspar occur much less, and accessory minerals are represented in trace. The semi-quantitative mineralogical analysis obtained by the X-ray powder diffraction (XRPD) method of the mica concentrate amount to: mica approximate to 55%, chlorite/clays approximate to 35%, quartz approximate to 5%, feldspars (plagioclase and K-feldspars combined) approximate to 5%.

Kaolinisani granit čine kaolin, feldspat, kvarcni pesak i liskun. Nakon odvajanja kaolinske komponente koja se nalazi u najsitnijoj frakciji ispod 0,043 mm i frakcije iznad 0,63 mm, ostaje klasa -0,63+0,043 mm koja sadrži kvarcni pesak, feldspat i liskun. U radu su dati rezultati flotiranja liskunskih minerala iz polimineralne sirovine uzete iz ležišta „Bašića bare“ – Kobaš, Srbac, Republika Srpska. Rezultati su pokazali da se postupkom flotacijske koncentracije može dobiti koncentrat liskuna, dok u otoku flotiranja ostaju feldspat i kvarcni pesak. U koncentratu liskuna sadržaj SiO2 je 52,70%, a Al2O3 24,6%. Rendgenskom difrakcionom analizom je određen semikvantitativni udeo pojedinačnih minerala: liskuni ~55%, minerali hlorita/glina ~35%, kvarc ~5%, plagioklasi i K-feldspati zajedno ~5%.

This paper investigates grinding of mineral mixtures with different grindabilities in the Bond ball mill. Understanding the ore mixture grinding is of great importance in mineral processing. The energy required for crushing and grinding is presented by the Bond work index and is determined by means of Bond grindability test. This paper presents the experimental results of the Bond work index values obtained by the standard method on limestone and andesite samples, as well as composite samples made up from these ore in different weight ratios. Comparatively are shown the Bond work index values that are obtained by the mass fraction of components that make up the composite samples calculation and their differences from the real value. During the Bond work index value determining, changes in the composition of the grinding products and circulating mill charge were monitored.

This paper presents the results of tests carried out to determine how the dosage of bentonite added as binder, affects the properties of green pellets made of the limestone fines that originate from Lithothamnium limestone processing. Bentonite was added to limestone in different mass fractions (1, 2.5, 5 and 10%), whereas all the other parameters of the pelletizing process remained constant. The aim of pelletizing was to consolidate limestone fines and form mechanically stable pellets, provided that all the other properties of limestone remain unchanged. The pellets formed in this way were analysed applying DTA/TG analysis and FTIR and SEM analyses. The results showed uniform distribution of bentonite in the pellets, demonstrated that the pellets are compact and there is no formation of new compounds. The pellets were tested for resistance to impact, compressive strength and abrasion resistance. Also disintegration tests were performed to determine the time required for the pellet to disintegrate completely in water. These mechanical properties are essential for transport, handling, storage and general use of pellets. The values of most of the parameters established for pellets with 5% bentonite, meet the standards required for use in agriculture for liming acid soils, however their application is limited because their impact resistance is unsatisfactory and the time required for their complete disintegration in water is extremely short. It should be noted that further increase of bentonite content (over 10%) will not improve the quality of green pellets. In view of the results obtained, it is necessary to introduce drying into the pelletizing process in order to bring the green pellets into solid state.