Sustainable and economically feasible polluted sediment treatment is gaining more and more importance. Stabilization/solidification (S/S) technologies are widely used for treatment of sediment and possibilities of using low-cost and readily available materials and binders are increasingly being examined. This work is concerned with aquairing more data about long-term performance of this kind of treatment in therms of metal leaching and microstructural cnaracterization when treating sediment with fly ash and lime. Extraction potential of metals and the effectiveness of the S/S treatment applied, together with compliance with national legislative, were performed by using Toxicity Characteristic Leaching Procedure TCLP and The German standard leaching test DIN 3841-4 S4. Leaching test results showed that the applied S/S treatment was effective in immobilizing metals even after seven years of aging. Scanning electron microscope (SEM) and X-ray diffraction analysis confirmed that pozzolanic reactions took place during 28 days and continued along S/S mixture maturation. Compressive strength measurement further proved the treatment efficacy in terms of obtained matrix stability, which enables their subsequent use. It can be concluded that the S/S technique, with the usage abundant materials has a significant potential for treatment of metal polluted sediment.

In this paper, for characteristic polytropic change of state of ideal gas is given graphical planimetric graphical representation of the most important energy values in workplace and thermal diagram, trough the appropriate area. In this paper, we used differential forms of First and Second law of thermodynamics and basic equation which define the observed change of state, written in a suitable form. The results for the polytropic change of state, are applied to the isobaric and isochoric change of state. It is shown that any of the energy values ( q12, w12, wt12, Δh12, Δu12) can be present in both workplace (p, v) as well as thermal (T-s) diagram. Graphical solutions, compared to the analytical, provide efficient theoretical explain and presentation of various thermo-dynamical processes of ideal gas with different aspects and greatly assist a clearer view of the problem and enhance each other living arrangement. Graphical representation of external influences or energy values shown in the diagrams, make it possible to more clearly we see connection between these effects, change of state, as well as their each other relations. This is particularly evident in the case when there are (p, v) and (T-s) diagram for a particular ideal gas, which is common in technical practices (e. g., air as an ideal gas).

U ovoj disertaciji proucavana je mogucnost primene crvenog mulja iz Fabrike glinice „Birac“ (Zvornik, severoistocna Bosna i Hercegovina) za izdvajanje jona nikla iz vodenih rastvora u sarcnim uslovima. U tu svrhu je ispitana efikasnost sorpcije u zavisnosti od uslova tretmana mulja i parametara sorpcije (pH, doza sorbenta, kontaktno vreme, inicijalna koncentracija jona nikla), kao i uticaja koegzistentnih jona. Stabilnost opteresenih sorbenata ispitina je u razlicitim ekstrakcionim rastvorima. Hemijskim i instrumentalnim metodama utvrđeno je da se ispitivani crveni mulj (BRM) odlikuje raznorodnim sastavom, malom specificnom povrsinom i visokim alkalitetom. Po hemijskom sastavu, ispitivani mulj predstavlja heterogenu smesu oksida gvožđa, aluminijuma, silicijuma i titana, pri cemu je oksid gvožđa predstavljao najzastupljeniju komponentu. Glavne kristalne faze u crvenom mulju bile su: hematit (Fe2O3), gibsit i bajerit (Al(OH)3), sodalit (Na8Si6Al6O24Cl2), kvarc (SiO2), anatas i rutil (TiO2), kao i kalcit (CaCO3). Prisustvo hidroksilnih, karbonatnih, Si(Аl)–О i Fe–O grupa na povrsini sorbenta, igra vacnu ulogu u vezivanju jona metala. Radi dobijanja efikasnijeg i ekoloski prihvatljivijeg sorbenta primenjeni su ispiranje, termicki i kiselinski tretmani. Temeljnim ispiranjem polaznog uzorka dobijen je sorbent (RBRM), istog mineralnog sastava, ali nice pH vrednosti i tacke nultog naelektrisanja (pHPZC). Termicki i kiselinski tretmani su, u zavisnosti od temperature tretmana i koncentracije kiseline, izazvali fizicke i hemijske promene uzorka znacajne za sorpciju. Najznacajnije promene pri termickom tretmanu su gubitak gibsita, bajerita i kalcita i strukturna destrukcija i transformacije sodalita. pHPZC ispranog uzorka carenog na 600 °C (RBRM600) znacajno je visa od vrednosti polaznog RBRM, a bliska je vrednosti sirovog mulja. Pri kiselinskom tretmanu, porast koncentracije kiseline doveo je do gubitka sodalita i kalcita, i rastvaranja kvarca. Nakon kiselinskih tretmana pHPZC je znacajno opala...

Cooling systems are very important for the functioning of industry and energy facilities. The most common problems in open cooling systems are: corrosion, deposits and biological growths. In this work we covered the subjects of: causes and effects of deposit creation and the protection of the cooling system against deposit creation. The dosage of inhibitors - deposit preventing agents was determined experimentally, with and without dosing corrosion inhibitors. Polymaleate was used as a deposit inhibitor here. The results showed that the success of deposit inhibition depended on the degree of thickening, i.e. the salt concentration in the system. Another important factor is the use of corrosion and deposit inhibitors. In the case of using corrosion inhibitor based on phosphonates, the consumption of polymaleates is decreased by up to 30% due to the synergetic effect of phosphonates and polymaleates.

In this paper, starting from general tangent equation in arbitrary point of specified curve, using principles of differential geometry and given mathematical transformation tangent equation of polytrophic function in p – v diagram was obtained. This form is convenient for solving numerous practical and theoretical problems in engineering thermodynamic by means of graphical method. It was shown that tangent can be constructed easily, using polytrophic equation only, but it is not example with other functions appearing in thermodynamics. Later, in this paper, we have given some methods, which refer to more exact construction of polytrophic and graphical analyze of polytrophic process.