Journal of Engineering & Processing Management (EPM)
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GEOTHERMAL ENERGY OF THE REPUBLIC OF SRPSKA AND HYDROCHEMICAL ASPECTS OF ITS EXPLORATION AND EXPLOITATION
Full text linkOne of the most used renewable energy sources worldwide is geothermal energy. It represents the heat, originated by natural processes happen in the Earth interior. The hot springs phenomena are the most frequent natural manifestation of geothermal activity. Geothermal potentiality of some area can be estimated based on geothermal gradient. Geothermal gradient is a conductive terrestrial parameter that represents the degree of increasing of the Earth temperature vs. depth. It is usually expressed in ⁰C/m or ⁰C/km. Different areas have different thermal gradients and thus different geothermal potential. Generally, higher geothermal gradients correspond to areas containing more geothermal energy. Geothermal characteristics of the territory of the Republic of Srpska are closely related to its complex geological setting. It is the reason why geothermal characteristics are different from area to area. Higher geothermal potentiality is recognised in the northern parts of the entity, in the first order in Semberija, Posavina and Banja Luka regions. The use of geothermal energy with different fluid temperatures can be considered throughthe Lindal diagram, who firstly proposed acomprehensive scale with appropriate temperatures for different uses. High temperature fluids are mostly used for electricity production and moderate and low temperature fluids for the direct use.Despite the fact that the territory of the Republic of Srpska has favourable geothermal properties, utilization of this kind of renewable energy resource is inadequate. Especially indicative are data about the use of geothermal energy by heat pumps (in bad sense) in comparison with praxis of developed countries. Chemical composition of thermal waters plays very important role and can be used in its exploration stage, for analyses of possibility of its use and for prediction of exploitation effects, as well. This kind of renewable energyresource, highly ecologically recommended, must be considered more seriously in the future in the Republic of Srpska. Furthermore, it must be put into the energy strategic documentsin appropriate manner
TREATMENT OF GROUND WATER CONTAMINATED OIL DERIVATIVES
No full textTreatment of groundwater is the most important part of the scope of protection of natural resources, because no biological and bacteriological water there is no life on the planet. Implemented through consideration of all the negative elements in the water, determine the percentage of their toxicity and finding the most appropriate method for their removal. The aim is to monitor, improve water quality and the environment in general observed
DEFINING REGULATING PARAMETERS OF SODIUM DITHIONYTE Na2S2O4
No full textDithionites of sodium and zinc (Na2S2O4 and ZnS2O4), also known asn hydrosulphites, are efficient reducing materials widely used in various industries.Mosto common application of Na2S2O4 is in textile industry and also as important ingredient in painting, printing and bleaching materials. In pharmacy it is widely used for drugs synthesis, in foof industry for fruit syrups bleaching, edible oil and gelatyne. During the experiment we tested parameters of Na2S2O4 dithionites synthesis by reducing sulphuric acis with zinc powder. Results of experiment clearly indicate that most appropriate temperature for synthesis is around 400C, reaction time 65 minutes at constant mixer speed and continuous cooling.
 
RESEARCH OF CHARACTERISTICS OF PROCESS NEUTRALIZATION OF ACID WASTEWATER BY LIME SLUDGE
No full textLime sludge which is generated in the industrial processes of water softening is a significant environmental and economic burden, due to increasingly stringent of national and international regulations relating to the management of waste streams. The high content of calcium carbonate in this material opens the possibility of its application in the processes of acidic waste water neutralization. In this paper, a research of characteristics of the process of neutralizing the acidity of water in terms of different initial pH value and flow regime, applying lime sludges which are generated in treatment of salt and fresh water, was conducted. Results of research showed that the initial pH value of water and the presence of NaCl have a significant effect on the solubility of calcium carbonate in the process of neutralization, while the examined flow regime (mixing speed of magnetic stirrer) had a negligible impact
EFFECT OF LIGHT ON THE AGING, CORROSION, AND DEGRADATION OF MATERIALS, IN RELATION TO THE ENHANCED REMOVAL OF ORGANIC POLLUTANTS
Full text linkA review on advanced photochemical processes influencing properties of materials is presented. Particular emphasis is given on photolytic processes for the removal of pollutants. Separately are presented methods for the removal of biological pollution. Major concern is paid to the methods for removal of persistent chemical pollutants. Two major groups of processes are known: homogenous and heterogeneous photocatalytic methods. The heterogeneous photocatalysis is usually done with semiconductor nanoparticles, capable to absorb light. In semiconductor the absorption of light quanta is connected with the promotion of electron(s) from valence to conduction band, leaving a positively charged hole(s) in CB. Electrons and holes can react with adsorbed molecules including water molecules. In this way the reactive intermediates are produced, which upon the sequence of reactions end with complete mineralization of ingredients. The scaling-up of heterogeneous photocatalytic process is closely connected with efficacy of them. As a matter of fact, many factors are involved in kinetics of photocatalysis: concentration of pollutants; concentration of catalyst; temperature; radiant flux; quantum yield; dopants; etc. The interrelations among various parameters are mostly nonlinear, and construction of the photoreactor is very demanding task. In last 30 years a lot of study was done, and general conclusion is that TiO2 (mostly anatase) is most efficient photocatalyst, but there is a lot of work needed on improvement of such processes
PREDICTING THE BALLISTIC STRENGTH OF ULTRA HIGH MOLECULAR WEIGHT POLYETHYLENE/FIBER COMPOSITES BY IMPLEMENTING FULL FACTORIALEXPERIMENTAL DESIGN
Full text linkThe purpose of the study is to predict the ballistic strength of hard ultra-high molecular weight polyethylene fiber/phenolicballistic composites by implementing the full factorial experimental design. When designing ballistic composites two major factors are the most important: the ballistic strength and the weight of the protection. The ultimate target is to achieve the required ballistic strength with the lowest possible weight of the protection. The hard ballistic UHMWPE/phenolic composites were made by the open mold high pressure, high-temperature compression of prepreg made of plain woven UHMWPE fiber fabric and polyvinyl butyral modified phenolic resin.The preparation of the composites was done in accordance to the 22 full factorialexperimental design. The areal weight of composites was taken to be the first factor and the second – fiber/resin ratio. The first factor low and high levels are chosen to be 2 kg/m 2 and 9 kg/m 2 , respectfully and for the second factor – 80/20 and 50/50, respectfully. The first-order linear model to approximate the response i.e. the ballistic strength of the composites within the study domain (2 – 9) kg/m 2 x (80/20 – 50/50) ratio was used. The influence of each individual factor on the response function is established, as well as the interaction of the two factors. It was found out that the estimated first-degree regression equation with interaction gives a very good approximation of the experimental results of the ballistic strength of composites within the study domain
DEVELOPMENT AND OPTIMIZATION OF CARVEDILOL FORMULATION USING EXPERIMENTAL DESIGN
Full text linkThe aim of this paper was to develop and optimize the carvedilol tablets formulation using the full factorial design. The content of binder (PVP K30), content of disintegrant (crospovidone) and main compression force were used as the independent variables. Tablets were prepared by wet granulation. The percentage of released carvedilol from prepared formulation after 10 minutes was defined as the response. It has been found that formulation with the low content of binding agents (4.8%), high content of disintegrant (4.5%) and compression force of 50 N has the best profile of drug. The optimal formulation was defined based on implementation of pharmaceuticaltechnological tests (testing strength, friability, disintegrating, contents of drug substance, drug release profiles). The stability of the optimal formulation with carvedilol was estimated using the aging tests
INFLUENCE OF 4A ZEOLITE SYNTHESIS PROCESS PARAMETERS ON WATER SORPTION CAPACITY
No full textThis paper studies the effect of process parameters on the sorption characteristics of zeolite 4A. The observed process are related to the influence of crystallization temperature, crystallization time and influence concentrations of Na2O. In parallel with the examination of the impact of these parameters on the capacity of water sorption of zeolite 4A, which was the primary goal, are analyzedinfluence on the adsorption capacity of dibutyl phthalate (DBF) synthesized powders as well as crystallinity and average size of the resulting particles of the zeolite. The results show that the capacity of water sorptione zeolite 4A increases with temperature and crystallization time, and decreased with increasing concentrations of Na2O. The influence of given parameters DBF adsorption, and the mean particle size is less prominent. Crystallinity also shows a significant dependence on temperature
SYNTHESIS 4-NITRO-41'-BIPHENYL BY CROSS-COUPLING REACTION
No full textBiphenylsarean important class of organic compounds. Theyare importantin the field of natural products, polymersand the contemporary medical materials. Synthetic route cross-coupling (Suzukis) reaction, starting from benzenevia the iodoniumsaltto 4-nitro-4'-metilbiphenyl is chosen in this study. The resulting intermediates and final product of the synthesis was confirmed by determination of the melting point and infrared spectroscopy. The final product was confirmed by NMR spectroscopy. This synthetic pathway to obtain biphenyls, which may be a key intermediate in many syntheses, there area number of advantages over the previously-defined synthetic routes due to the tolerance in respect of a wide range of functional groups, regio and stereoselectivity and specificity. In addition, theinorganic productsin the synthesis of non-toxic so farbeen used as heavy metals (Hg (II), Tl(III), Pb(IV)) and can be easily separated. High yields of the reaction products are obtained
DETERMINATION OF CHANGE IN CONTENT OF HEAVY AND RADIOACTIVE METALS IN DRINKING WATER BY AN INDIRECT ANALYSIS METHOD BASED ON SCALE TESTS
Full text linkIn this paper the content of metal in drinking water was determined in two samples, one from 2008 and other from 2010, by the indirect method based on the analysis of scale, which had originally been suggested by Rajkovic and associates. Received results confirmed that drinking water according to the metal content was of constant level (metals are lower than MAC values), but with increased content of U. By the method of fraction extraction it was proved that increased content of U regarded mainly to natural U, and less to U of anthropogenic origin. The increased content of isotope 90Sr was also noticed, probably as the effect of increased presence of alkaline earth metals. The analysis structure of scale by the usage of SEM determined that the dominant form was calcium carbonate of crystal structure of hexagonal shape which corresponded to calcite. By Röentgen diffraction analysis of dust it was determined the content of calcite which contained CaO; MgO; FeO; MnO and CO2 and it belongs to medium manganese calcites. All the analyses done in this paper, confirmed that indirect method of determination of metal content had been reliable and applicable for determination of low concentrations of metals in drinking water