HEAVY NON-FERROUS METALS | |
ArticleName | Distribution of non-ferrous metals, arsenic and antimony during plumbous slags sulfidizing impoverishment by copper-zinc concentrate |
DOI | 10.17580/nfm.2016.02.03 |
ArticleAuthor | Dosmukhamedov N. K., Zholdasbay E. E. |
ArticleAuthorData | Metallurgy of Non-ferrous Metals Department, Kazakh National Research Technical University after K. I. Satpayev, Almaty, Kazakhstan: N. K. Dosmukhamedov, Professor, e-mail: nurdos@bk.ru |
Abstract | The existing technology of semiproducts and reverts processing is characterized by a number of disadvantages, the main of which are low non-ferrous metals recovery into target products and considerable accumulation of arsenic and antimony in the primary production process because of their low recovery into dust. Along with the raw materials, a considerable proportion of arsenic and antimony is received with converter slag, which constitutes 26% in the total volume of the raw material. With converter slag, up to 30% of the total arsenic volume in the charge comes to the process. The present paper is dedicated to solving a problem of arsenic and antimony deep sublimation from slag to dust and withdrawing them out of the process chain in the form of non-toxic sulfide compounds. Results of the converter slag recovery-sulfiding depletion by the sour copper-zinc concentrate are presented in the paper. Experimentally is proved a possibility of the slag deep non-ferrous metals, arsenic and antimony depletion with matte and metal lead obtaining in condensed phases. It is established that on charging a fresh portion of the copper-zinc concentrate, excess sulfur arising as a result of the principal sulfides dissociation is completely spent for arsenic oxide and antimony sulfidizing. In conditions of high temperature (1573 К), the Gibbs free energy of arsenic oxide and antimony sulfidizing is as follows: ΔG1573К = –862.40 kJ/mol and ΔG1573К = –746.9 kJ/mol respectively, that is almost 2 times greater than the values of the Gibbs free energy of the interaction reactions of non-ferrous metals and ferric oxides with elemental sulfur. High values of the Gibbs free energy testify an arsenic and antimony deep sublimation to dust as non-toxic sulfides As2S3 and Sb2S3. The impurities sublimation completeness depends on consumption of the principal sulfides (excess sulfur) fed with concentrate: the greater is the introduced excess sulfur quantity, the greater is an arsenic and antimony sublimation to dust. It is shown that on the converter slag with high lead content treatment with different sour concentrate consumption, the highest possible lead extraction to lead bullion and copper extraction to matte are achieved. It was determined that at temperature of 1573 К and optimum concentrate consumption of 20%, extraction of copper to matte is 96%, extraction of lead to lead bullion is 92% and extraction of zinc to slag is 87%. Besides, high arsenic and antimony extraction to dust is achieved with amounts of 82% and 78% correspondingly. It is demonstrated that the copper content in the matte is decreasing as the concentrate consumption rises above 20%. It is determined an equilibrium composition of the obtained products. Listed are the results of copper, lead, zinc, arsenic and antimony distribution among the melting products. The obtained results are applied to the calculation of initial charge with new composition in case of semiproducts and reverts of the lead industry processing in combination with the copper-zinc concentrate under the shaft concentrating conditions. Use of the new technology will significantly reduces coke consumption in the smelting process and guarantees straight processing of a collective difficult-to-process copper-zinc concentrate for one stage. As this take place, high results of both copper extraction to matter and zinc extraction to slag are achieved. Also, as a result of arsenic and antimony deep sublimation to dust, it is provided their maximum withdrawing out of the process, thereby essentially rising quality of the obtained products. |
keywords | Slag, copper-zinc concentrate, impoverishment, non-ferrous metals, arsenic, antimony, recovery, matte, lead bullion, distribution |
References | 1. Dosmukhamedov N. K. Teoreticheskiye i tekhnologicheskiye osobennosti pererabotki promproduktov i oborotnyh materialov tsvetnoy metallurgii (Theoretical and technological peculiarities of processing of non-ferrous metallurgy middlings and reverts). Almaty : DPS, 2008. 360 p. 2. Zholdasbay E. E., Kabylbekov Zh. Zh., Fedorov A. N., Dosmukhamedov N. K. Osobennosti perekhoda medi, myshyaka i surmy iz medno-svintsovogo shteina v chernovoy svinets (Pecuiliarities of copper, arsenic and antimony transition from copper-lead matte into lead bullion). Tsvetnye metally = Non-Ferrous Metals. 2015. No. 3. pp. 5–10. |
Full content | Distribution of non-ferrous metals, arsenic and antimony during plumbous slags sulfidizing impoverishment by copper-zinc concentrate |