Naslov (srp)

Karakterizacija nestandardnih koncentrata bakra i mogućnosti njihove prerade : doktorska disertacija

Autor

Mitrovski, Aleksandra M. 1977-

Doprinosi

Štrbac, Nada. 1964-
Živković, Dragana, 1965-
Kamberović, Željko, 1968-
Mihajlović, Ivan.
Sokić, Miroslav.

Opis (eng)

Knowledge of the composition and characteristics of the non-standard sulphide type copper concentrates, thermodynamic and kinetic parameters, mechanisms of oxidative roasting process, as well as the technological possibilities for the separation of impurities and the implementation in the conventional pyrometallurgical copper production, represent some of the important aspects that were surveyed in the frame of this doctoral dissertation. For the experimental investigations three sulphide polymetallic copper concentrates, one enargite-type raw ore material and three synthesized mixtures, made from the initial concentrates with the addition of certain amounts of Pb, Zn, Ni and Cd in the form of sulfides in order to obtain non-standard concentrates, were selected. Characterization included: 1) determination the chemical composition of the initial samples by ICP-AES, AAS, electrogravimetry and EDXRF; 2) determination the mineralogical composition of the initial samples and products of oxidative roasting by XRD analysis; and 3) the microstructural analysis of the initial samples and products of oxidative roasting by SEM-EDS methods and optical microscopy. Due to better understanding of the thermodynamic properties of non-standard copper concentrates, thermodynamic analysis of oxidation process in the system Cu-S-Me-O (Me = Fe, Pb, Zn, As, Ni, Cd, Hg and Sb) was done. Phase Stability Diagrams as a functions log pSO2 = f (log pO2) were constructed at temperatures from 25 °C to 1000 °C. The values of ΔG0T at 450, 650 and 900 °C for the possible reactions in the investigated Me-S-O systems were calculated. Equilibrium composition diagrams were constructed and mole fractions of gas and concentrate (batch) for the optimal oxidation process were determined. The behaviour of the each batch component during heating up to 1000 ° C was analysed. Thermal analysis in isothermal and non-isothermal conditions was performed by DTA-TG- analysis under which the oxidation mechanisms of investigated concentrates and mixtures were defined. For defining the kinetic parameters of oxidative roasting process, the kinetic analysis of the experimental results for the initial concentrates and synthesized mixtures was done, using the methods of isothermal (Sharp’s method) and non-isothermal kinetics (methods of Kissinger and Ozawa) and activation energies of the oxidation were determined. The impacts of harmful impurities in copper concentrates and influence of temperature and time on kinetic parameters of the process were analysed...

Opis (srp)

Poznavanje sastava i karakteristika nestandardnih koncentrata bakra sulfidnog tipa, termodinamiĉkih i kinetiĉkih parametara, mehanizama procesa oksidacionog prţenja koncentrata, kao i tehnoloških mogućnosti za odvajanje štetnih primesa i ukljuĉivanje u konvencionalnu pirometaluršku proizvodnju bakra, neki su od vaţnih aspekata obuhvaćenih istraţivanjem u okviru ove doktorske disertacije. Za eksperimentalna istraţivanja bila su odabrana tri polimetaliĉna koncentrata bakra sulfidnog tipa, jedna rudna sirovina enargitskog tipa i tri sintetisane mešavine polaznih koncentrata sa dodatkom odreĊene koliĉine Pb, Zn, Ni i Cd u obliku sulfida u cilju dobijanja nestandardnih koncentrata. Karakterizacija je obuhvatala: 1) odreĊivanje hemijskog sastava polaznih uzoraka putem ICP-AES, AAS, elektrogravimetrije i EDXRF; 2) odreĊivanje mineraloškog sastava polaznih uzoraka i produkata oksidacionog prţenja putem XRD analize; i 3) mikrostrukturne analize polaznih uzoraka i produkata oksidacionog prţenja putem SEM-EDS metode i optiĉke mikroskopije. U cilju boljeg poznavanja termodinamiĉkih karakteristika nestandardnih koncentrata bakra, izvršena je termodinamiĉka analiza procesa oksidacije u sistemu Cu−Me−S−O (Me = Fe, Pb, Zn, As, Ni, Cd, Hg i Sb) i konstruisani su dijagrami stabilnosti faza (Phase Stability Diagrams) kao zavisnosti log pSO2 = f ( log pO2) na temperaturama od 25 °C do 1000 °C. OdreĊene su vrednosti ΔG0T na 450, 650 i 900 °C za moguće reakcije u ispitivanim Me-S-O sistemima. Konstruisani su dijagrami ravnoteţnog sastava i odreĊeni odnosi gasa i koncentrata (šarţe) za optimalne uslove procesa oksidacionog prţenja koncentrata. Analizirano je ponašanje svake od prisutnih komponenti šarţe tokom zagrevanja do 1000 °C. Termijska analiza vršena je putem DTA-TG analize u neizotermskim uslovima na osnovu koje su definisani mehanizmi procesa oksidacije ispitivanih koncentrata i sintetisanih mešavina. Za definisanje kinetiĉkih parametara procesa oksidacionog prţenja koncentrata bakra, izvršena je kinetiĉka obrada eksperimentalnih rezultata polaznih koncentrata i sintetisanih mešavina, primenom metoda izotermske (metoda Sharpa) i neizotermske kinetike (metode Kissingera i Ozawe) i odreĊene energije aktivacije procesa oksidacionog prţenja koncentrata. Analiziran je uticaj koliĉine prisutnih štetnih primesa u koncentratima bakra, temperature i vremena na kinetiĉke pokazatelje procesa oksidacionog prţenja...

Opis (srp)

Metalurško inţenjerstvo-Ekstraktivna metalurgija / Metallurgical Engineering-Extractive Metallurgy Datum odbrane: 27.03.2015.

Jezik

srpski

Datum

2015

Licenca

Ovo delo je licencirano pod uslovima licence
Creative Commons CC BY-NC-ND 2.0 AT - Creative Commons Autorstvo - Nekomercijalno - Bez prerada 2.0 Austria License.

http://creativecommons.org/licenses/by-nc-nd/2.0/at/legalcode

Predmet

non-standard copper concentrates, characterization, harmful components, thermal analysis, oxidation mechanism, PSD diagram, factorial design

nestandardni koncentrati bakra, karakterizacija, štetne komponente, termijska analiza, mehanizam oksidacije, PSD dijagram, faktorski dizajn