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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 results of investigations of the possibility of using 'Gigovići'-Ulcinj 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 relatively high CaCO3 content of 98.16 %, as well as low MgCO3 content of 1.53 % and low silicate content (SiO2 0.30 %). 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 (85.25 %) 'Gigovići' limestone cannot be used in pharmaceutical and cosmetics industry. Due to relatively high content of MgO (0.73 %) and Fe (340 ppm), as well as high content of heavy metals, Cu (18 ppm), Ni (24 ppm) and Cd (9 ppm), 'Gigovići' limestone cannot be used, in production of cattle feed and for neutralization of acidic soils.

Carbonate filler is an important mineral commodity, with rather diverse industrial applications. The Bjelopavlići area in Montenegro is rich in chemically pure limestone, which was preliminary explored in the field, and further on mineralogical, petrographic, geochemical and technological properties were studied. The obtained results have proven the high quality of limestone from the studied deposits, as it can be used for paints&varnishes, rubber&plastics, metallurgy, foundry, sugar, fertilizers and animal feed industry. Several deposits have very pure limestone, that can be also used for paper, glass, pharmacy and soil neutralisation. The potential resources of high quality limestone are around 23 million tons. [Projekat Ministarstva nauke Republike Srbije, br. OI176016]

In this paper are presented the results of testing the possibilities of improving the technological process evaluation lithothamnium limestone deposits 'Dobrilovići' - Loznica in order to obtain a new range of products including: flue gas desulphurization (ODG), as feed additive and for liming acid soils. The results showed that the limestone from this deposit may be used for ODG as it meets the requirements of the required quality for use in these purposes. In fact, the raw materials meet the requirements for obtaining a powder (bulk) gypsum. Comparing the characteristics of the resulting range to be used as a feed additive ('fodder chalk') and the requirements to be met by this product, we can say: selective excavation and selecting a particular size class can get this range of products. The results of laboratory tests of briquettes obtained from lithothamnium limestone have shown that it is possible to obtain briquettes of a satisfactory quality. Values of parameters of the mechanical properties of briquettes increases with the share of bentonite as a binder in the samples. This increase in samples with mass proportion of binder to 5% is a linear growth, while for the samples containing more than 5% of binder that trend is minimal. Therefore, there is no need to produce briquettes with more than 5% of bentonite. Based on the results of laboratory tests, authors have proposed technological scheme by which is possible complete evaluation of the limestone deposit 'Dobrilovići'. With adaptation of existing technology line in the firm Department for Agriculture 'Loznica' Ltd. (which owns the mine limestone 'Dobrilovići') can be obtained three new product range.

This paper presents the importance of limestone in a variety of industries with a special focus on the use of limestone as filler in the industry of polyvinyl chloride (PVC). Of Out of all fillers, used in the industry of PVC processing, calcium carbonate type of fillers are 80%. Fillers are used in order to improve various mechanical properties of polymer such as tensile and breaking properties, density, bending strength, hardness, thermal stability, viscosity and more. Latest trends of industrial development and demands of the processing industry for high quality carbonate fillers influenced the implementation process of surface modification limestone and calcite, which is the main constituent of fine micronized limestone in order to enhance its performance.

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 thermogravimetric (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. [ABSTRACT FROM AUTHOR]

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The effect of the combined actions of milling and hydrophobization procedures applied in construction composites synthesis was investigated. The mortars were prepared with cement (CEM I 42.5) and calcite aggregate complying the standard 1:3 mix ratio. The limestone filler (10 wt%) was added to the mixture upon its mechano-chemical activation in an ultra-centrifugal mill. The activation variables (milling time, rotor velocity, sieve mesh size) were altered to achieve the optimal quality of the powder. The treatment was optimized via chemometric tools. The r 2 values (0.955–0.998) of second order polynomial models accurately predicted the output and the Standard score analysis chose the optimal activation parameters: 4.25 min; 48.58 m/s and 80 μm sieve. The selected filler and all three aggregate fractions were coated with stearic acid via dry procedure. The mortar mixes, prepared with uncoated (M1) and coated (M2) aggregate and filler, were cured for a period of 28 days during which compressive strength and water absorption were monitored. The dimensional changes in mortars were estimated via TMA dilatometer measurements. Thermo-analytical methods (DTA/TGA) were applied in the thermal behavior analysis. Mineralogical and morphological changes in the structure of hardened composite were detected by XRD and SEM, respectively. Limestone aggregate led to lower final compressive strengths in mortar, but it produced an infinitesimally small shrinkage at 1000 °C. The hydrophobization via stearic acid initiated the decrease in water absorption and formation of needle-like micro-network that filled structural voids reducing open porosity. The assessment of the effects of limestone utilization as a filler and as an aggregate on the mortar performances confirmed that this novel water-repellent composite is applicable in structural design. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)