Investigation Of Beneficiation Of Silver From Kutahya-gumuskoy Silicified Tuff Ore

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 1995Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 1995Bu çalışma kapsamında, Kütahya-Gümüşköy maden yatağındaki silisifîye tüf cevherinden gümüşün zenginleştirilme olanakları araştırılmıştır. Cevhere boyuta sınıflandırma, gravite, flotasyon yöntemleri uygulanarak, gümüşçe zengin ön konsantre elde edilmeye çalışılmış ve ön konsantreler üzerinde siyanürle çözündürme deneyleri yapılmıştır. Kütahya-Gümüşköy Aktepe maden yatağı mineralojik yapılan ve gümüş içerikleri farklı beş tür cevherden oluşmaktadır. Bunlardan silisifîye tüf cevheri toplam rezervin yaklaşık % 50'sini oluşturmaktadır. Silisifîye tüf cevheri üzerinde yapılan mineralojik incelemeler; cevher bileşiminde başlıca, nabit gümüş, pirarjirit, arjantit, gümüşlü tetrahedrit, kuvars, feldispat, barit ve kil minerallerinin varlığı saptanmıştır. Cevherin gümüş içeriği 320 g/t 'dur. Silisifîye tüf cevherindeki kil mineralleri, ıslatma, ardından yaş eleme ve aktararak dağıtma işlemleri uygulanarak uzaklaştırılmaya çalışılmıştır. Cevherin sadece 24 saat ıslatılıp, ardından yaş elenmesiyle, numunenin ağırlıkça % 12.3'ünün, % 6'lık bir gümüş kaybıyla 38 mikron altında atılabileceği; 24 saat ıslatmayı izleyen aktararak dağıtma işlemi ve yaş eleme sonucu cevherin ağırlıkça % 21-22.5'inin, yaklaşık %10 Ag kaybıyla, 38 mikron altında uzaklaştırılabileceği saptanmıştır Aynı zamanda kilin büyük bir kısmının bu üründe toplandığı gözlenmiştir. Cevher üzerinde yapılan jig ve sarsıntılı masa ile zenginleştirme deneyleri sonucunda, gümüşçe zengin bir ürün elde edilememiştir. Cevherdeki sülfür rninerallerini kazanmak için boyutu 0.106 mm altında olan kilsiz, ön konsantrede etil ve amil ksantat kullanılarak, toplu sülfür flotasyonu yapılmış, %2.522 Ag içerikli toplu sülfür konsantresi, %25.2 Ag verimiyle kazanılmıştır. Toplu sülfür flotasyonu artığına, ayrıca barit flotasyonu uygulanarak %94.4 BaSÛ4 içerikli barit konsantresi, %70.5 BaS04 verimiyle elde edilmiştir. Tuvenan cevher ve kilsiz ön konsantre üzerinde doğrudan siyanürle çözündürme deneyleri yapılmıştır. Liç deneyleri sonucunda Ag çözünme verimi, 72 saat sonunda tuvenan cevher için, %72.8, ön konsantre için %80.6 olmuştur. Çözeltideki Ag konsantrasyonları, tuvenan cevher için 99.7mg/L ön konsantre için 119 mg/1 olmuştur. En iyi çözündürme koşullarında, NaCN tüketimi %19.1, CaO tüketimi, %21.2 azalmıştır.Silver, a brilliant white metal that could be kept for a long time was undoubtedly attractive. The latin name for silver, argentum, is derived from latin root meaning white, brilliant. Silver rarely occurs natively, but is most often contained in sulfides of nonferrous metals ( zinc, lead, etc.) present in metallic ores. Silver was one of the first metals to be used by man, as were gold and copper. Since ancient times, silverware has been handed down in Southern Europe and Middle East. Silver bullion and cut pieces of the metal were used as an instrument of exchange. The earliest large scale workings of silver were in Eastern Asia Minor some time in the 4th millennium B.C. In Turkey, The researchers indicated that the silver mining in Gümüşköy-Kütahya with the period of Phyrigian Kingdom II. Two principal types of silver mineralization occur in nature: native silver deposits where silver is mined as one of the main commercial metals and deposits where copper, lead, zinc, gold, nickel and some other metals are the dominant constituents, with silver being an impurity. Native silver deposits constitute not more than 10% of the world resources of silver. The World's principal resources of silver are concentrated in deposits with a disseminated mineralization, from which the silver extracted as a by product during the processing of other metals. In this study, the possibilities of recovering silver from silicifled tuff ore were investigated by the laboratory tests which was carried out on raw ore and clay free preconcentrate. vm Kütahya-Gümüşköy silver ore deposits are located in Western Anatolia. Five types of ores (altered tuff, dolomitle ore, manganiferous ore, dump ore and silicified tuff) with varying mineralogical composition and silver content are found in the ore deposits. One type of these ores is silicified tuff ore. This ore constitutes nearly 50 % of the reserves in Kütahya-Gümüşköy silver ore deposits. Mineralogical studies revealed that the ore consisted of silver minerals such as native silver, argentite, pyrargyrite, silverous tetrahedrite. Barite, galena, sphalerite, chalcopyrite, pyrite, hematite, psilomelane, calcite, quarz and clay minerals also accompany these silver minerals. The silver content of the ore is 320 g/t. Most silver minerals are found mainly under 0.05 mm in size. Due to the presence of 10-22 % amount of clay minerals, soaking followed by wet screening and tumbling tests were carried out on the ore in order to remove clay minerals from the samples below 10 cm in size. Tumbling tests were accomplished in a drum which has 60cm diameter and 30 cm height. The samples were tumbled in the drum for 15 minutes after soaking of 12 and 24 hours. Wet screening then applied to the tumbled material. After soaking followed by tumbling tests, 21 - 22.5 % of the ore having minus 0.038 mm in size with a silver loss of about 10% was obtained. At the end of the only wet screening test following 24 hours of soaking, it was determined that most of the clay minerals was collected below 0.038 mm in size and 12.3 % of the ore was removed with a silver loss of nearly 6 %. The gravity concentration tests were carried out on the clay free samples by Harz jig and standart Wilfley shaking table. After reducing the size of ore -6mm, the jig tests were carried out on the samples in -6 +3.36 mm and -3.36 +1.0 mm size fractions. The shaking table tests were resulted that by means of these methods obtaining clean preconcentrates from the samples with high recoveries was not possible. rx The flotation tests were carried out in a laboratory type Denver cell with different sizes. The flotation conditions for bulk sulphur flotation and barite flotation are presented below: BULK SULPHUR FLOTATION BARITE FLOTATION Since the amount of sulphur minerals were not sufficient in the ore, three flotation tests were done under the same conditions in order to the combined bulk concentrate. The Barite flotation tests were conducted using tailings of the bulk sulphur flotation. The sulphur flotation tests resulted in a bulk sulphur concentrate assaying 2.5% Ag with a recovery of 25.2 % Ag. According to this result, 25 % of the silver minerals in the ore bounded to the sulphur minerals. This bulk concentrate can be sent to smelter in order to recover metallic silver. In the barite flotation tests, 1500 g/t of sodium oleate and 1000 g/t of sodium carbonate reagents were used. This flotation test yielded a barite concentrate assaying 94.4 % BaS04. According to the crude ore the content of this concentrate was nearly 10 % BaS04 and 62.6 % BaS04 recovery was obtained. The cyanidation tests were conducted in 2 1 beaker and the pulp was mixed at 400 rpm by a mechanical stirrer. The effects of NaCN concentration, the amount of protective alcanity, the amount of Pb(N03)2, pulp density and particle size were investigated on the raw ore in order to determine the optimum leaching conditions. During the tests, aliquots were taken periodically from the solution for measuring NaCN, CaO, 02, Ag concentrations and pH of the solution. Y The optimum conditions given below were determined by preliminary tests carried out on the raw ore. NaCN concentration Protective alkaline addition Amount of Pb(N03)2 Pulp density Particle Size Pulp Temperature 1.5g/l; 0.8 g/1 CaO; 350 g/t ; 30 %; - 0.106 mm (d80= 0.056 mm); 20 ± 2 °C The silver leaching recoveries of 66.5 % and 72.7 % were obtained after leaching times of 48 hours and 72 hours, respectively. Also NaCN and CaO consumptions were 1.31kg/t and 11.75 kg/t, respectively. The total Ag recovery obtained after the leaching time of 72 hours has been 73.2 % based on raw ore. The cyanidation tests were carried out also on the clay-free pre concentrate. In these tests the optimum conditions were selected the same as raw ore because the behaviors of the silver minerals did not affect cyanide leaching. Optimum cyanidation conditions are given below: The silver leaching recoveries of 70.3 % and 80.6 % were obtained after leaching times of 48 hours and 72 hours, respectively. Also NaCN and CaO consumptions were 1.06 kg/t and 9.26 kg/t, XI respectively. The total Ag recovery obtained after the leaching time of 72 hours has been 73.4 % based on raw ore. As a result of this experimental study, It can be concluded that the clay minerals affects the leaching recovery and the reagent consumptions, and It was also determined that the leaching recoveries increased nearly 10% by removing the clay minerals and the reagent consumptions decreased. NaCN and CaO consumptions were 19.1% and 21.2% respectively on the optimum leaching conditions.Yüksek LisansM.Sc

Pressure Leaching Of Küre Masive Rich Ore

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2002Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2002Bu çalışmada, Küre cevher yatağından alınan masif zengin bakır cevherinin basınç altında liçi araştırılmıştır. Deneylerde süre, sıcaklık, oksijen kısmi basıncı, katı konsantrasyonu, asit konsantrasyonu, katalizör olarak gümüş iyonları ilavesinin ve mekanik aktivasyonun metal çözünme verimleri üzerindeki etkileri araştırılarak optimum çözündürme koşulları belirlenmiştir. Optimum deney koşulları 160C sıcaklık, 0.4 M H2SO4 konsantrasyonu, 20 bar oksijen kismi basıncı, 50 g/l katı konsantrasyonu ve 120 dak. liç süresi olarak bulunmuştur. Bu koşullarda bakırın %95, kobaltın %70, çinkonun %97 ve nikelin %80’i çözeltiye alınabilmiştir. Ortama az miktarda gümüş iyonları ilavesinin liç prosesinde hızlandırıcı etkisi olduğu tesbit edilmiştir. Mekanik aktivasyon sonrası liç işleminde yüksek çözünme verimleri elde edilmiştir. Aktivasyon sonrası düşük sıcaklıklarda bile (110oC), 10 bar oksijen basıncı altında liç yapıldığında, yaklaşık bakırın %98, kobaltın %75, çinkonun %97 ve nikelin %93’ü çözeltiye alınabilmiştir. Deneyler sonunda Pb, Ag ve Au liç artıklarında toplanmıştır. Mekanik aktivasyon uygulamasıyla masif zengin cevherdeki metallerin çözünme hızlarının yaklaşık % 50 oranında arttığı tesbit edilmiştir.The aim of this study was to investigate the possibility of recovering metallic values from Küre massive rich copper ore by the pressure leaching. For this purpose massive rich copper ore taken from Küre-copper ore deposit was used. The effects of time, temperature, partial oxygen pressure, solid concentration, acid concentration, silver ion addition as a catalyst and mechanical activation on metal leaching recoveries were investigated and optimum leaching conditions were determined. The optimum leaching conditions were found as 160C temperature, 0.4 M H2SO4 concentration, 20 bar partial oxygen pressure, 50 g/l solid concentration, and 120 min leaching time. Approximately 95% of Cu, 70% of Co, 97% of Zn and 80% of Ni were extracted under the optimum leaching conditions. Silver ions could be added in small quantities for enhancing the leach process. Mechanical activation followed by pressure leaching of Küre massive rich copper ore resulted in high metal dissolution efficiencies. It was found that, when activated, this ore could be hydrometallurgically processed in low temperature of 110C and an oxygen partial pressure of 10 bars. Approximately 98% of Cu, 75% of Co, 97% of Zn and 93% of Ni extraction could be achieved. Pb, Ag, and Au stayed in the leach residues and could be recovered from there. By mechanical activation, the leaching rates of metals from massive rich ore were increased about 50 %.DoktoraPh