HYDROMETALLURGICAL AND FLOTATION METHODS OF SLAG DEPLETION

АННОТАЦИЯ

«Алмалыкский ГМК» является одним из крупнейших промышленных предприятий Республики Узбекистан кроме того, оно  ориентировано на выпуск экспортируемой продукции. В результате многолетней переработки  медных концентратов медеплавильного завода  АГМК  накоплено  более 7 млн. т отвальных шлаков медного производства. В настоящее время часть старых шлаков МПЗ перерабатывается в АГМК МОФ-2 флотационным способом и извлекается медь, золото, серебро. Анализ современного состояния технологии переработки шлаков показывает что наиболее предпочтительной для вовлечения  шлаков  в переработку и получения из них железа является технология низкотемпературного восстановления с последующей  магнитной сепарацией металлизованной фазы от немагнитной фракции.

ABSTRACT

"Almalyk MMC" is one of the largest industrial enterprises of the Republic of Uzbekistan, in addition, it is focused on the production of exported products. As a result of many years of processing of copper concentrates of the copper smelting plant AMMC, more than 7 million tons of waste slag of copper production have been accumulated. At present, part of the old slag from the Copper smelter is processed at AMMC CCF-2 by the flotation method and copper, gold, and silver are recovered. Analysis of the current state of slag processing technology shows that the most preferable for involving slags in processing and obtaining iron from them is the low-temperature reduction technology with subsequent magnetic separation of the metallized phase from the non-magnetic fraction.

Ключевые слова: шлак, обжиг, концентрат, флотация, отход.

Keywords: slag, burning, concentration, flotation, waste.

Slag hydrometallurgy is used only at the Gatsila plant (India), where it replaced flotation, since the latter did not give satisfactory results in the extraction of nickel and cobalt [1]. Melting slag in suspension, containing, %: 1.76 Cu; 0.23 Ni; 0.19 Co; 33.6 SiO₂, are leached with a solution of ferric chloride, the FeCl₃ consumption is 5 times higher than the stoichiometric one. Slag size -0.053 mm, leaching time - 6 h, extraction into solution, %: 54 Cu; 77Ni; 44 Co. It is planned to use this method also at the plant "Khetri" for a mixture of flash smelting slags and converter slags. At other enterprises, either slag flotation or their electrothermal depletion is used. Technical indicators of flotation of converter slags, depending on their composition, are given in Table. 1.1.

Table 1.1.

Technical indicators for slag flotation, %

Good indicators of slag flotation are achieved only when they are slowly cooled. This is due to the fact that in slowly cooled slags sulfide particles have a particle size of 0.015-0.04 mm, in normally and rapidly cooled slags their particle size is much smaller. However, slowly cooled slags have greater abrasiveness and hardness. At foreign plants, slag flotation is carried out in separate workshops with higher quality structural materials for grinding equipment. At the enterprises of the CIS, where slag flotation is carried out together with ore, there are difficulties with equipment wear, so slow cooling is not used. Almalyk MMC carries out flotation of converter slags together with ore and separately with SOF AMMC in an amount of up to 30% of its mass. Extraction of copper is 80-85% [4].Converter slag flotation is used in almost all copper plants using autogenous processes, since the removal of converter slag improves the performance of the main smelters.

The flotation of slags with a high copper content from the Noranda process (Canada) is characterized by a high copper content in the tailings [5]. This is due to the need to obtain super-rich concentrates with a copper content of 40-60%. Flotation is mainly carried out by converter slags, in some cases flash smelting slags.

The chemical composition of converter slag entering the flotation processing and the form of finding copper, as well as the results of converter slag flotation at some foreign plants are given in Table. 1.1. The Balkhash copper smelter (Kazakhstan) processes imported concentrates along with its own raw materials; The largest suppliers (more than 10.0 thousand tons of concentrate per year) are Erdenetsky (Mongolia), Nikolaevsky, Dzhezkazgansky, Ushalinsky and Tishinsky mines. As of December 1, 2006, 36,737 thousand tons of copper slags were stored in the slag dump with reserves of 472,306 tons of copper in them, with an average content of 0.80%. Slag output varies from 336 to 727 thousand tons per year; the copper content in them varies from 0.7 to 0.87%.The main parameters of slag dumps (as of January 1, 1995): length - 1 km, height - 20 m, occupied area - 49 hectares, density - 3.4-3.5 t/m3, volumetric weight 3.2-3.5 t/ m3. Chemical composition, %: Cu-0.41-0.50, Pb - 0.16-0.23, Zn - 0.4-1.5, Fe - 30-40, SiO₂ - 38-42, A1₂O₃ -6-12, CaO-12-14, Re-0.00005, Mo-0.01-0.02, Au-0.1-0.4 and Ag - 4-6 g/t. The slags are not toxic, the admixture of As is 0.02-0.04%, and it is bound into insoluble compounds with iron and calcium. Mineral composition: glass-50-80%, anorthite 1-10%, magnetite, copper sulfides. Stocks of metals in slags (as of 1997): Cu - 156 thousand tons, Au - 12.4 kg, Ag - 0.16 tons, Mo - 0.006 thousand tons, Pb - 0.06 thousand tons, Fe - 10.8 thousand tonsIn terms of iron content (25-30%), they are close to iron ores. Due to the admixture of certain alloying metals (tungsten, nickel, cobalt, etc.), steel is obtained by reducing iron. There is experience in the extraction of iron at the Balkhash Mining and Metallurgical Complex. Here, the flotation method annually extracts up to 500 thousand tons. iron concentrate. A technology has been developed and a feasibility study has been drawn up for the processing of dump slags from a medical plant at a concentrating plant.The most economical and expedient is the processing of slag at existing facilities due to some reduction in the processing of poor off-balance ores from the Koungrad open pit. With an annual volume of slag processing of 1200 thousand tons with a copper content of 0.53%, the output of concentrate should be 28.9 thousand tons with a copper content of 15%. There are proposals for the processing of slags from the Balkhash plant by the cementation method using carburized cast iron, which allows the most complete extraction of non-ferrous, rare and noble metals and iron. Crushed stone and slag can be made from depleted slags. Pilot tests for the processing of copper-smelting slags by the flotation method were carried out back in the 70s. Then the extraction of copper into concentrate was 70%. With separate processing of copper smelting slag, the extraction of copper into concentrate can reach 90%. The proposed capacity of the enterprise is 1 million tons of slag per year. In 1995, during the flotation enrichment, an additional 26.2 thousand tons of copper concentrates were obtained from 304.8 thousand tons of processed slags. Since 1990, complex processing of slag from copper-smelting production with the production of copper and iron concentrates has been carried out by the TVETMET enterprise, later by the Kazakh-American joint venture Kenzhetai.The Dzhezkazgan copper smelter processes copper concentrates from the Dzhezkazgan concentrator, as well as imported and imported raw materials. Share of own concentrates is 90-95%.

Bibliography:

1. К.С. Санакулов, А.С. Хасанов ,,Переработка шлаков медного производства’’ Ташкент Издательство «Фан» Узбекистан  2007 г.
2. Хасанов А.С., Сирожов Т.Т., Уткирова Ш. И., Муртозаева М.М. “Исследование влияния хлоридовозгоночного обжига переработки  медных шлаков” UNIVERSUM: ТЕХНИЧЕСКИЕ НАУКИ  №3 (84).
3. Хасанов А.С., Толибов Б.И., Сирожов Т.Т., Ахмедов М.С. “Новые направления по созданию технологию грануляции шлаков медного производства” ЕВРАЗИЙСКИЙ СОЮЗ УЧЕНЫХ (ЕСУ). № 2 (71) / 2020
4. Сирожов Т.Т., Арипов А.Р., Уткирова Ш., Жумаев М. “Современное состояние теории и практики подготовки шлаков медного производства” Academy. № 1 (52), 2020.
5. Эшонқулов У.Х, Олимов Ф.М, Саидахмедов А.А, Туробов Ш.Н, Сирожов Т.Т., Шодиев А.Н. “Обоснование параметров контурного взрывания при сооружении горных выработок большого сечения в крепких  породах” Научно-методический журнал.  Достижения науки и образования. №19 Россия. 29-декабрь. 2018 года. 10-13с.
6. Хасанов  А.С, Толибов Б.И, Сирожов Т.Т, Ханнонова М, Нурмуродов М.Н. “Переработка медных шлаков с извлечением цветных и черных металлов”. Кончилик ва нефт-газ тармоқларининг муаммолари ва инновацион ривожлантириш йўллари  номли республика илмий-амалий анжумани, НДКИ Узбекистан Навоий шаҳри. 2016-йил 8-9 апрель 273 б.
7. Туробов Ш.Н, Каршибоев Ш, Саидахмедов А, Сирожов Т.Т.,  Ярлакабов С. Намазов С.З. “Исследование возможностиизвлечения ценых компонентов из техногеннқх отходов” «Advances in Scien» XI Международная научно-практическая конференция. 30-ноября 2017 года Научно-издательский центр «Актуальность РФ» 118-120с