Trakya - Binkılıç yöresi düşük tenörlü manganez cevherlerinin zenginleştirilmesi

Abstract

Çalışmada öncelikle, manganez yataklarının tasnifi ve bu yatakların ihtiva ettiği manganez mineralleri çizelgeler halinde belirtilerek, manganez yataklarının büyük bir çoğunluğunu teşkil eden ve endüstride düşük içerikte olmaları nedeniyle, kısıtlı olarak kullanılabilen, düşük tenörlü manganez cevherlerinin zenginleştirilmesi, çeşitli cevher hazırlama yöntemleriyle verilmiştir. Yurdumuzda manganez madenciliği açısından önemli bir yeri olan ve büyük bir potansiyel ihtiva eden Trakya bölgesi manganez oksit yataklarının Jeolojisi ve Jenezi belirtilerek, bölgede mevcut üç büyük manganez yatağından bir tanesi olan Binkılıç yöresi manganez cevherlerinden alınan numuneler üzerinde mineralojik etüdler yapılmıştır. Etüdler neticesinde; kireçtaşı-wad çimento maddesi içinde piroluzit, psilomelan ve manganit tespit edilmiştir. Cevherin ana gang mineralleri kalsit ve bir miktarda kuvars'dır. Trakya-Binkılıç yöresine ait olan manganez oksit cevherlerine zenginleştirme yöntemleri üç ayrı yoldan yürütülmüştür. 1. Plotasyon İle Zenginleştirme: % 36.40 Mn. (% 51.12 MnO2) içeren tuvönan cevheri ile yapılan flotasyon deneyleri; manganez minerallerinin ve kalsit'in yüzdürülme denemeleri olmak üzere iki yoldan yürütülmüştür. Mangan minerallerinin yüzdürülme deneyleri, kalsit gangının bastırılamaması nedeni ile başarılı olamamıştır. Kalsit flotasyonu deneylerinde (ters flotasyon); tane boyutu, toplayıcı cinsi, toplayıcı miktarı, toplayıcı kıvam zamanı, pH değeri, pülpte katı oranı, pülp sıcaklığı, bastırıcı reaktif cinsi, bastırıcı reaktif miktarı, sodyum silikat miktarı ve işlem miktarının tesirleri incelenmiştir. Deneylerden elde olunan en iyi sonuç ve şartlar altında yapılan flotasyonlarda, elde edilen nihaî artığın (flotasyon batanı) tenoru % 51.40 Mn (% 74.22 MnO2), verimi ise % 70.31 bulunmuştur.IV Manganez konsantresinde bulunan +2 değerlikli mangan minerallerinin oksitlenmesiyle, flotasyon manganez konsantresindeki Mn02 içeriği % 74. 22` den % 80. 72 'e yükseltile- bilmektedir. 2. Manyetik Ayırma ile Zenginleştirme: % 37.34. Mn (% 50.16 MnO2) içeren aynı özelliklere sahip cevherle yapılan deneylerde; 2,5 Amper (105 Volt) değe rinde, % 50.82 Mn (% 69.47 MnO2) tenor ve % 82.02 verimle bir manyetik mangan konsantresi alınmıştır. Manyetik konsantre verimi, 2 Amper (80 Volt) değerinde % 47' e düşürülerek tenor % 52.89 Mn'a (% 72.50 Mn02) yükseltilebilmektedir. 3. Gravite ile Zenginleştirme: Cevherin -2.00 + 0.841 mm boyut grubu Jig ile, 0,841 mm. Altı ise üç boyut grubu halinde ayrı ayrı tabla'da konsantre edilmiştir. Jig 'de en iyi konsantreyi elde etmek maksadı ile, genlik ve zaman faktörlerinin etkileri incelenmiş ve en iyi şartlarda çalışılarak, % 38.50 Mn. içeren cevherden % 48.50 Mn. tenor ve % 64.25 verimle bir Jig manganez konsantresi alınmıştır. üç boyut grubu halinde sarsıntılı tabla' ya beslenen % 36.51 Mn. içeren cevherden, % 49.98 Mn tenor ve % 60.47 verimle bir tabla manganez konsantresi alınmıştır. Netice olarak; Gravite deneylerinde, Jig ve sarsıntılı tabla beraber kullanılarak, % 37.34 Mn. (% 50.16 Mn02) içeren tuvönan cevherden deneyler neticesinde; % 49.31 Mn. (% 67.50 Mn02) tenor ve % 62.09 verimle bir gravite manganez konsantresi elde edilebilmektedir. Endüstride, özellikle batarya ve kimya sanayii kollarında kullanılan manganez oksit cevherlerinde aranan aktivitenin neyi ifade ettiğini ve bu değerin nelere bağlı olduğunu saptamak amacıyla; Aktivitenin toplam Mn, Mn02 içeriği, tane boyutu, bünye suyu ve mineral cinsi ile ilişkilerini ortaya koyan deneyler yapılmıştır. Deneylerde yurdun hemen hemen her yöresinden alınan manganez mineralleri ile manganez cevher numuneleri kullanılmıştır. Manganez oksit cevherlerinde aktivite değerinin en fazla etkinliği olan minerallerin psilomelan ve piroluzit olduğu saptanılmıştır. Psilomelan'ın aktiviteye etkinliği piroluzit' e nazaran daha fazladır. Elde edilen neticelerden; Aktivite, MnO2 içeriği ve % karışım (psilomelan + pirolusit) arasındaki ilişkiyi veren bir abak (diyagram) düzenlenmiştir. +2 ve +3 değerlikli manganez oksit mineralleri aktiviteye etken olmadıkları için, bir manganez oksit cevherin-de, psilomelan + piroluzit miktarı'% 100 alınarak mikroskop etüdleri ile bulunacak olan karışım oranı, numunenin MnO2 içeriği ve aktivite delerlerinden iki tanesi bilindiği taktirde, diğer üçüncüsü abaktan direkt olarak okunabilecektir.

The majority of the manganese ores available in the world today have a Mn. content of about 35 % which needs to be inereased för use in metallurgical, chemical and battery- making industries.` The increase in Mn concent is achived by various physical up-grading and metallurgical methods. Mn 35 %. These ores meet the requirements of the liron-and-Steel Industry, but are inadeguate for use in other fields. in fact, 80 % of the ores used in the chemical and battery-making in¬ dustries are imported, while the demand for ferro-manganese is entirely supplied from abroad. Almost 80 % of the manganese öre production in this country is obtained.from the Trakya Region, where 30 milyon tons of are reserves were estimated in 1966. The manganese ores of this region cohtain 20-35 % Mn and necessitates beneficiation. Hence, the beneficiation studies that has been carried out in this research work is believed to contribute to the development of manganese industry in Turkey. in this thesis/ a table showing the classification of the manganese öre deposits known in the vrorld today, is given together with their Mn. content. Also, the importance of low-grade manganese ores is emphasized and methods'of their beneficiation is reviewed. The geological details were examined for the depo¬ sits of manganese oxide in Trakya and mineralogical studies were carried out on the öre samples taken. Studies showed the existance of pyrolusite, psilomelane and manganite mineralein Limestone-wad cement. The maîn gang minerals of the ores consisted of calcite with small amounts of guartz. Öre samples taken from the Binkılıç district were subjected to the following methods of beneficiation: 1. Beneficiation by Flotation: Flotation studies were carried out on an are con- taining 36.40 % Mn (51.12 % MnO2). Two alternatives were used. in the first, the flotation of manganese minerals and in the second the flotation of the gang mineral (calcite) were in- vestigated. The flotation of the manganese minerals was found to be inaffective due to the difficulty of depressing the calcite gang. in experiments carried out for the calcite flotation (reverse flotation) the effects of partide size, type of collector, amount of collector, conditioning period for the collector, pH value, solid ratio of the pulp, pulp tempera- ture, type of depressing reagent, amount of depressing reagent, amount of sodium silicate and slimes were investigated. The results obtained are summerized below. a)Partide Size: Öre samples ground to minus 0.300, 0.212, 0.150, 0.106, 0.074 and 0.044 mm. were used and the best results were achieved with the minus 0.106 mm. size. b)Type of collector: Anionic type of collectors including oleic acid, linoleic acid and sodium oleate were used and oleic acid was found to be the most suitable. c)Amount of collectors Oleie acid, having been found the best collector, was used in amounts of 1,2,3,4 and 5 kg/ton, of which 3 kg/ton gave the best results. d)Conditioning time for the collector: The collector was conditioned for 0,5,10 and 15 minutes. 5 minutes of conditioning gave the best results.e)pH value: Plotation tests were carried out at various pH values ranging between 10.5 and 11. The results were plotted on a graph from which the best pH value was obtained as 10.7. f)Solid ratio of the pulp: Various solid ratioes of the pulp were employed between 20-35 % and the best ratio was found to be 30 %. g)Pulp temparature: A series of flotation tests were carried out at temperatures ranging between 6-50°C and the best results were obtained at room temperature (22°C). h) Type and amount of depressing reagent: Dextrin and püre starch were used in various amounts for depressing the manganese oxides-. -But, both of the depres¬ sing reagents were found to have no useful effect on the flotation. i) Amount of sodium,silicate: Sodium silicate nad no useful effect of the flotation. On the contrary, it tended to depress the calcite. j) Amount of slime: Öre sampies ground to minus 0.106 mm. were subjected to flotation tests, both before and after removal of the slimes. it was found that the slimes had no ili effects on the flotation. Flotation tests carried out under the best conditions produced a manganese concentrate (the flotation.sink) assaying 51.40 % Mn (74.22 % Mn02), with 70.31 % recovery. Mn02 Concent of the flotation sink could be raised from 74.22 % to 80.72 % by subjecting the Mn++ in the manga¬ nese concentrate to oxidation at 300°C for 2 hours. The per- centage of Mn02 thus obtained is suitable for use in the battery-making industry.2.Beneficiation by Magnetic Separation: A high-intensity dry magnetic separator was used for this purpose. Separation at 2,5 A (105 V) produced a concen- trate assaying 50.82 % Mn (69.47 % Mn02), from an öre con- taining 37.34 % Mn. The recovery was 82.02 %. Separation at 2 A (80 V) increased the concentrate assay to 52.89 % Mn (72.50 % MnO2), while reducing the recovery to 47 %. The con¬ centrate thus obtained was found unsuitable for battery-making but could be suitable for the metallurgical industry. 3.Beneficiation by Gravity Separation: The öre was crushed to minus 2 ıran. and then divided in to two fractions. The -2.00 + 0.841 mm. fraction was con- centrated by jigging and the minus 0.841 mm. fraction was concentrated by tabling. Effect of variables such as stroke and speed were investigated in a laboratory Hartz Jig, and with the best conditions determined, a manganese concentrate was obtained with an assay value of 48.50 % Mn at 64.25 % recovery, from an öre containing 38.50 % Mn. A laboratory Wilfley table was used for tabling. Experiments carried out under 0.841 mm. in three separate fractions produced a manganese concentrate assaying 49.98 % Mn with a recovery of 60.47 %, from an öre containing 36.51 % Mn. Combined results of jigging and tabling showed that a final cencentrate with 49.31 % Mn (67.50 % MnO2) and 69.09 % recovery could be achieved by gravity concentration of an öre containing 37.34 % Mn (50.16 % MnO2). This concentrate is suitable for use in the metallurgical industry. Battery-making and chemical industries reguire a certain degree of activity in the manganese oxide within the öre concentrates. For this reason, the activity was investi¬ gated in relation to total Mn, MnO2, partide size, inherent water and the type of mineral. The work was done on a large number of manganese öre samples obtained from various regions in Turkey.The activity was found to be effected mainly by psilomelane and pyrolusite minerals, the effect of the first being greater. The results of experiments were used to prepare a diagram showing the relationship between the activity, Mn02 and the proportions of the psilomelane and pyrolusite mine rals in the ore. The diagram can be used to find the value of any of the three variables, knowing the other two. The sum of the amounts of psilomelane and pyrolusite minerals. Is taken as 100 %, and their proportions are determined by microscopic examination, when required.