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Pronalazak jeste postupak interaktivnog tretmana dve vrste otpada koji nastaju tokom primarne proizvodnje bakra u cilju dobijanja bakra. Prvi je oksidna raskrivka nastala iskopavanjem sulfidne rude bakra, koja sadrži alumino-silikatne minerale (70-80%), karbonate alkalnih i zemnoalkalnih metala (10-20%), gvožđe (5-10%) i bakar (0,10-0,20%). Druga vrsta otpada je otpadna voda iz topionice bakra sa visokim sadržajem kiseline (pH<0,90), rastvorenog bakra (≥0,50 g/l) i procesnih nečistoća. Interaktivni tretman podrazumeva mešanje oksidne raskrivke i kisele otpadne vode u hidrometalurškom reaktoru pri čemu se interaktivni efekat ogleda u istovremenim procesima neutralizacije kiseline i luženja bakra. Tretirana otpadna voda (pH≥0,90 i koncentracija Cu ≥1,0 g/dm3), dobijena interaktivnim tretmanom, je pogodna za dobijanje bakra kao katodnog bakra procesom solvent ekstrakcije/elektrovininga. Interaktivnim tretmanom otpada se smanjuje njihov štetan uticaj na životnu sredinu, smanjuje količina odloženog otpada, smanjuje gubitak bakra kroz otpadne tokove i pri tom dobija rastvor pogodan za dobijanje bakra.

Tehničko rešenje obuhvata procenu količine otpadne vode i koncentracije zagađujućih materija (ukupne suspendovane čestice, koncentracije sulfata i metala – Fe, Pb, Zn, Cd, As, Sb, Cu, Ni) u zavisnosti od mesta nastanka; definisanje tretmana otpadnih voda u skladu sa najbolje dostupnim tehnikama za oblast primarne i sekundarne industrije olova i izbor inovativnog rešenja tretmana otpadnih voda čijom se primenom obezbeđuje zadovoljavajući kvalitet prečišćene vode za ponovno korišćenje u radu predmetnog kompleksa (sistem recirkulacije tehničke vode) ili ispuštanje u okolinu. Tehničko rešenje za tehnološki postupak tretmana otpadnih voda nastalih na predmetnom postrojenju u Zajači uključuje hemijsko taloženje metala u obliku hidroksida (Fe, Pb i Cu) i sulfata (SO42-) u obliku kalcijum-sulfata (CaSO4) dodavanjem 15 mas.% rastvora kalcijum-hidroksida (Ca(OH)2) i adsorpciju zaostalih jona metala (Zn, Cd, Ni, Sb i As) na prirodnom/modifikovanom zeolitu. Inovativni deo tehničkog rešenja jeste simultana modifikacija prirodnog zeolita rastvorom soli gvožđe(III)-hlorid (FeCl3) koji se ujedno koristi kao koagulant u tretmanu otpadne vode. Fe–modifikovani zeolit ima izražen afinitet prema katjonima metala zaostalim u rastvoru nakon prvog stepena prečišćavanja, kao i afinitet prema oksoanjonima arsena i antimona koji se ne mogu ukloniti metodom taloženja hidroksida. Primena inovativnog tehničkog rešenja ima za cilj pozitivan uticaj na tehno-ekonomsku analizu procesa, koji se ogleda u povećanju efikasnosti postupka prečišćavanja uz smanjenje broja procesnih koraka, smanjenje upotrebe hemijskih reagenasa i primeni ekonomski isplativog i lako dostupnog prirodnog zeolita koji bi omogućio efikasno uklanjanje katjona metala, ali i oksoanjona antimona i arsena. Efikasnost inovativne tehnologije je eksperimentalno potvrđena.

Low-cost and easily available natural zeolite is a promising adsorbent for metal ions removal in wastewater treatment. The possibility of using zeolitic tuff from Serbia in the form of Na-enriched natural zeolite (Na-Z) for the adsorption of Pb2+, Zn2+, Cu2+, and Ni2+ions from wastewater was investigated in the presented paper. The research included Na-Z characterization and determination of adsorption kinetics in individual ion adsorption tests using Weber-Morris intraparticle diffusion model, non-linear pseudo-first-order (PFO), pseudo-second-order (PSO) and mixed-order (MO) kinetic models. The results indicate that the adsorption processes of metal ions on Na-Z are complex processes dominated by multiple rate-limiting mechanisms and best defined by the MO model. The mechanisms of ion diffusion and adsorption to active sites are equally represented in the Pb2+adsorption process. The mechanism of ion adsorption on the active sites is the rate-limiting step in the Zn2+adsorption process, while in the case of the Cu2+and Ni2+adsorption ion diffusion is the rate-limiting kinetic mechanism. Within the MO model, the PFO rate (external/internal diffusion) and the PSO rate (adsorption on active sites) were calculated and results wereapplied to a multicomponent wastewater sample in order to determine and explain the adsorption efficiency in wastewater treatment. The results show that the rate of adsorption of individual metal ions and the efficiency of ion removal from a multicomponent wastewater sample are influenced by several factors including the radius of the hydrated ion and the free energy of hydration. The achieved removal of metal ions by Na-Z is Pb2+(89%) > Cu2+(72%) > Zn2+(61%) > Ni2+(58%) and defines Na-enriched naturalzeolite as an effective adsorbent in wastewater treatment.

More than 90% of lead produced in Europe comes from secondary lead flows, of which 85% is attributed to waste lead-acid batteries (LAB). The main technological approach for LAB processing implies pyrometallurgy by which 100–400 kg of waste slag (WS) is generated per 1 ton of produced metallic lead. Due to recycling process parameters, generated WS has great potential for releasing toxic elements contributing to environmental pollution [1]. Namely, the most common flux in the recycling process is sodium-based (Na2CO3) when alkali lead waste slag (ALWS) is generated, characterized as hazardous due to its physical-chemical characteristics: high leachability, hygroscopic and pulverized nature and, ultimately, instability [2,3]. Therefore, ALWS treatment prior to disposal should be considered an integral part of waste LAB treatment systems. Immobilization of toxic elements contained in slag is crucial and can be achieved by stabilization/solidification processes (S/S) as one of the most widely used technologies in the treatment of heavy metal-containing wastes for final disposal or utilization. In this research, ALWS generated in the waste LAB recycling is used to determine the S/S process efficiency as a function of the added binder amount (cement, in the range of 5 – 10 %), pre-treatment (the removal of water-soluble compounds), and activator addition (MgO). The liquid to solid (L/S) ratio was 1/4 in all S/S experiments. The basic parameters for the effectiveness assessments were compressive strength (UCS) and pollutants leaching (Method 1311 Toxicity characteristic leaching procedure, TCLP). ALWS containing 3.5 Pb, 15.5 Na, 14.0 S, and 24.7 Fe was mixed with cement and water. The results of UCS showed that all produced solidificates exceeded the required value of 0.35 MPa [4], yet the mixture containing 7.5 % of the cement has the best mechanical properties (2.1 MPa). This sample was further analyzed and the TCLP results showed that the Pb concentration exceeds the li

More than 90 % of lead produced in Europe comes from secondary lead flows, of which 85 % is attributed to waste lead-acid batteries (LAB). The main technological approach for LAB processing implies pyrometallurgy by which 100–400 kg of waste slag (WS) is generated per 1 ton of produced metallic lead. Due to recycling process parameters, generated WS has great potential for releasing toxic elements contributing to environmental pollution [1]. Namely, the most common flux in the recycling process is sodium-based (Na2CO3) when alkali lead waste slag (ALWS) is generated, characterized as hazardous due to its physical-chemical characteristics: high leachability, hygroscopic and pulverized nature and, ultimately, instability [2,3]. Therefore, ALWS treatment prior to disposal should be considered an integral part of waste LAB treatment systems. Immobilization of toxic elements contained in slag is crucial and can be achieved by stabilization/solidification processes (S/S) as one of the most widely used technologies in the treatment of heavy metal containing wastes for final disposal or utilization. In this research, ALWS generated in the waste LAB recycling is used to determine the S/S process efficiency as a function of the added binder amount (cement, in the range of 5 – 10 %), pre-treatment (the removal of water-soluble compounds), and activator addition (MgO). The liquid to solid (L/S) ratio was 1/4 in all S/S experiments. The basic parameters for the effectiveness assessments were compressive strength (UCS) and pollutants leaching (Method 1311 Toxicity characteristic leaching procedure, TCLP). The conclusion is that, contrary to the pre-treatment process, the addition of MgO has an overall positive effect on the S/S process of ALSW, ensuring both mechanical and chemical stability. This ALWS solidificate, obtained through the S/S process by using MgO as an activator, is safe for disposal, according to environmental regulations.

Acid mine drainage (AMD) is a waste from mining sites, usually acidic, with high concentrations of sulfates and heavy metal ions. This study investigates the AMD neutralization process using fly ash (FA) as an alternative material. Samples of FA from coal-fired power plants in Serbia (“Nikola Tesla” (EF) and “Kostolac” (KOST)) were analyzed and used. The results were compared with the treatment efficiency of commercial neutralization agent (NaOH). The alkaline nature of FA was the basis for use in the treatment process of the extremely acid Lake Robule (pH 2.46), located in the mining areas of eastern Serbia. The optimal S/L ratio for the AMD neutralization process determined for EF was 25 wt.%, and for KOST it was 20 wt.%. The mechanism of the neutralization process was analyzed using the ANC test and PHREEQC program. The element concentrations and pH values in solutions indicated that FA samples could neutralize Lake Robule with more than 99% of Al, Fe, Cu, Zn, and more than 89% of Pb precipitated. Formation of insoluble (oxy)hydroxide forms (Fe3+ and Al3+ ions) creates favorable conditions for co-precipitation of other trace metals (Cu, Zn, Ni, Pb, and Cd) from AMD, which is further enhanced by cation adsorption on FA particles. FA proved to be a more effective neutralization agent than NaOH due to its adsorption effect, while among the FA samples, KOST was more effective due to the aging process through the carbonization reaction. Using FA as an alternative material is a promising and sustainable method for treating AMD, with economic and environmental benefits.

Olovna alkalna šljaka je otpad koji se generiše u pirometalurškom procesu prerade olovnih sirovina, sa dodatkom topitelja natrijum(I)-karbonata (Na2CO3). U izradi doktorske disertacije ispitivan je kombinovani proces prerade olovnih sirovina iz primarnih i sekundarnih izvora, kao i mogućnost predtretmana, stabilizacije i solidifikacije industrijskog uzorka olovne alkalne šljake iz procesa reciklaže istrošenih olovnih akumulatora. U prvom delu istraživanja analiziran je proces topljenja olovnih sirovina u kratkoj rotacionoj peći, u laboratorijskim uslovima. U procesu su korišćeni olovni koncentrat (primarna sirovina) i desumporizovana olovna pasta (sekundarna sirovina), posle njihove detaljne karakterizacije, ispitivanja hemijskog i granulometrijskog sastava olovnog koncentrata, kao i hemijskog sastava desumporizovane olovne paste. Topljenje je ispitano u funkciji sastava šarže, temperature, rotacije i vremena zadržavanja materijala u peći. Efikasnost procesa topljenja je procenjena na osnovu ostvarenog stepena ekstrakcije olova iz sirovina, fizičko-hemijskih osobina (hemijski sastav, bazicitet, viskozitet) i količine generisane šljake. Najbolji rezultat efikasnosti ekstrakcije olova (98,38 %) je ostvaren u eksperimentu sa kombinovanim topljenjem olovnog koncentrata (50 %) i desumporizovane olovne paste (50 %). Generisana je šljaka u količini od 32 % u odnosu na masu polaznih sirovina, sa sadržajem 3,34 % olova, u kojoj su metodom rentgenske difrakcije (XRD - X-ray diffraction) identifikovane faze Na4Ca4(Si6O18), Fe2SiO4 i FeO(OH), manje količine faze CaFe2O4, i najmanje faze FeO. Zbog korišćenja relativno čistih sirovina u pogledu primesa, količina As u generisanoj šljaci je bila niska (0,003 %). Viskozitet generisane šljake od 60 P (kg/(m·s)), na temperaturi 1100 °C, bio je zadovoljavajući u pogledu dobrog razdvajanja šljake od metala, a izračunata vrednost baziciteta od 0,85 je ukazala na njen blago kiseli karakter. Drugi deo istraživanja obuhvatio je ispitivanje, Alkaline lead slag is a waste generated in the pyrometallurgical process of the recycling of materials based on lead with the addition of a sodium(I)-carbonate (Na2CO3) as a flux. The doctoral dissertation includes investigation of a combined process of recycling of lead materials from primary and secondary sources, as well as the possibility of pre-treatment, stabilization and solidification of the industrial sample of lead alkaline slag from the recycling process of spent lead acid batteries. In the first part of the research, the smelting process of lead materials in a short rotary furnace was examined in laboratory conditions. In the process, lead concentrate (primary raw material) and desumporized lead paste (secondary raw material) were used, after their detailed characterization including chemical and granulometric composition of the lead concentrate, as well as the chemical composition of the desumporized lead paste. The smelting process was tested in the function of the batch composition, temperature, rotation and process time in the furnace. The efficacy of the smelting process was estimated based on the achieved degree of extraction of lead from raw materials, physical and chemical properties (chemical composition, basicity, viscosity) and quantities of generated slag. The best result of the extraction efficiency of lead (98.38 %) was obtained in an experiment with combined smelting of lead concentrate (50 %) and desumporized lead paste (50 %). Slag is generated in the amount of 32 % in relation to the weight of the charge, with a content of 3.34% of lead. XRD analysis of the slag showed Na4Ca4 (Si6O18), Fe2SiO4 and FeO as the main phases (OH), less CaFe2O4, whereas FeO was the least present. Due to the use of relatively pure raw material in charge mixture, the amount of As in the generated slag was low (0.003 %). The viscosity of the generated slag was 60 P (kg/(m·s)) at 1100 ° C, which was satisfactory in terms of the good separation of the slag from th

Reuse of waste is one of the main principles of sustainable development and circular economy. Secondary alkaline lead slag is a hazardous waste generated in the recycling process of lead-acid batteries that may be suitable in construction materials. The environmental impact of the use of lead slag as a partial replacement of fine aggregates in the cement-based stabilization/solidification (S/S) process for the preparation of concrete was studied in this paper. Solidified products containing 10%, 15%, 20%, and 25% slag were laboratory tested by unconfined compressive strength (UCS) analyses and the Toxicity Characteristic Leaching Procedure (TCLP). At the same time, the leachability of toxic elements from solidified products with a high percent of slag was evaluated under environmental conditions for during one year. The results of the UCS and TCLP indicated that utilization of this type of slag in cement-based applications may be justified with its controlled addition. However, the described application of the slag was disputed due to the high release of As under high alkaline environmental conditions. Eh-pH analyses and the geochemical modeling using the software PHREEQC were evaluated, as well as the mechanism of pollutant (Pb, As) immobilization (precipitation, adsorption) as a function of pH conditions.

Alkaline lead slag is a waste generated in the pyrometallurgical process of the recycling of materials based on lead with the addition of a sodium(I)-carbonate (Na2CO3) as a flux. The doctoral dissertation includes investigation of a combined process of recycling of lead materials from primary and secondary sources, as well as the possibility of pre-treatment, stabilization and solidification of the industrial sample of lead alkaline slag from the recycling process of spent lead acid batteries. In the first part of the research, the smelting process of lead materials in a short rotary furnace was examined in laboratory conditions. In the process, lead concentrate (primary raw material) and desumporized lead paste (secondary raw material) were used, after their detailed characterization including chemical and granulometric composition of the lead concentrate, as well as the chemical composition of the desumporized lead paste. The smelting process was tested in the function of the batch composition, temperature, rotation and process time in the furnace. The efficacy of the smelting process was estimated based on the achieved degree of extraction of lead from raw materials, physical and chemical properties (chemical composition, basicity, viscosity) and quantities of generated slag. The best result of the extraction efficiency of lead (98.38 %) was obtained in an experiment with combined smelting of lead concentrate (50 %) and desumporized lead paste (50 %). Slag is generated in the amount of 32 % in relation to the weight of the charge, with a content of 3.34% of lead. XRD analysis of the slag showed Na4Ca4 (Si6O18), Fe2SiO4 and FeO as the main phases (OH), less CaFe2O4, whereas FeO was the least present. Due to the use of relatively pure raw material in charge mixture, the amount of As in the generated slag was low (0.003 %). The viscosity of the generated slag was 60 P (kg/(m·s)) at 1100 ° C, which was satisfactory in terms of the good separation of the slag from th, Olovna alkalna šljaka je otpad koji se generiše u pirometalurškom procesu prerade olovnih sirovina, sa dodatkom topitelja natrijum(I)-karbonata (Na2CO3). U izradi doktorske disertacije ispitivan je kombinovani proces prerade olovnih sirovina iz primarnih i sekundarnih izvora, kao i mogućnost predtretmana, stabilizacije i solidifikacije industrijskog uzorka olovne alkalne šljake iz procesa reciklaže istrošenih olovnih akumulatora. U prvom delu istraživanja analiziran je proces topljenja olovnih sirovina u kratkoj rotacionoj peći, u laboratorijskim uslovima. U procesu su korišćeni olovni koncentrat (primarna sirovina) i desumporizovana olovna pasta (sekundarna sirovina), posle njihove detaljne karakterizacije, ispitivanja hemijskog i granulometrijskog sastava olovnog koncentrata, kao i hemijskog sastava desumporizovane olovne paste. Topljenje je ispitano u funkciji sastava šarže, temperature, rotacije i vremena zadržavanja materijala u peći. Efikasnost procesa topljenja je procenjena na osnovu ostvarenog stepena ekstrakcije olova iz sirovina, fizičko-hemijskih osobina (hemijski sastav, bazicitet, viskozitet) i količine generisane šljake. Najbolji rezultat efikasnosti ekstrakcije olova (98,38 %) je ostvaren u eksperimentu sa kombinovanim topljenjem olovnog koncentrata (50 %) i desumporizovane olovne paste (50 %). Generisana je šljaka u količini od 32 % u odnosu na masu polaznih sirovina, sa sadržajem 3,34 % olova, u kojoj su metodom rentgenske difrakcije (XRD - X-ray diffraction) identifikovane faze Na4Ca4(Si6O18), Fe2SiO4 i FeO(OH), manje količine faze CaFe2O4, i najmanje faze FeO. Zbog korišćenja relativno čistih sirovina u pogledu primesa, količina As u generisanoj šljaci je bila niska (0,003 %). Viskozitet generisane šljake od 60 P (kg/(m·s)), na temperaturi 1100 °C, bio je zadovoljavajući u pogledu dobrog razdvajanja šljake od metala, a izračunata vrednost baziciteta od 0,85 je ukazala na njen blago kiseli karakter. Drugi deo istraživanja obuhvatio je ispitivanje

Sodium lead slag, generated during secondary lead production, is characterized as hazardous waste. The aim of the study was to investigate leaching mechanism and behaviour of lead and arsenic from sodium lead slag previously stabilized/solidified in concrete using additives: MgO, CaO, Ba(OH)(2) and gypsum. The influence of selected additives on pollutant release was also investigated. The results of the NEN 7375 leaching test indicate dissolution of lead and arsenic from the outer layer of specimens, followed by depletion of possible mobile forms. Analysis of leachates from samples with various compositions showed that proper selection of additives may reduce leaching of Pb and As below the specified limits.

This paper presents a preliminary design for treatment of mining and metallurgical wastewaters (MMW) from the basin of antimony “Zajača“, which contains high concentrations of arsenic and antimony. MMW have been investigated in laboratory, due to large difference in concentrations of pollutants. Metallurgical wastewaters were treated using iron (II)-sulfate and lime milk used to adjust the pH value at 7. After chemical treatment of metallurgical wastewater and its joining with mining wastewater, residual amount of arsenic in water was below maximum allowed concentrations, while the concentration of antimony, remained above the maximum allowed value. The final phase of purification process was performed using ion exchange resin. After treatment of MMW, they can be used as technical water in the smelting process of secondary raw lead materials.