[ABSTRAK Potensi cadangan bijih mangan di Indonesia cukup besar, namun terdapatdi berbagai lokasi yang tersebar di seluruh Indonesia. Komoditi ini menjadi bahanbaku yang tidak tergantikan di industri baja dunia. Ferromangan (FeMn)merupakan logam paduan dengan komposisi 75% Mangan (Mn) dan 25% besi (Fe)yang umumnya digunakan pada proses peleburan besi/baja guna memperbaikisifak-sifat mekanik dari produk yang dihasilkan.Penelitian ini dilakukan untuk mempelajari pengaruh proses pencanpuranbijih Mn kadar rendah (LG) yang berasal dari Kab. Tanggamus, Lampung (16,3%Mn-19,2 %Fe-20,2 %Si) dengan bijih Mn kadar menengah (MG) yang berasaldari Jember, Jawa Timur (27,7 %Mn-4,4 %Fe-14,7%Si) sebagai bahan baku untukpembuatan logam FeMn dengan kandungan minimal sebesar 50 %Mn. Penelitianini dilakukan sebanyak 5 kali percobaan dengan variasi pada campuran bijih Mnyaitu [1] 25 %LG+75 %MG, [2] 50 %LG+50 %MG, [3] 75 %LG+25 %MG, [4]100 %LG, dan [5] 100 %MG. Bijih mangan diproses menggunakan Submerged ArcFurnace (SAF) dengan input berupa bijih Mn sebagai bahan baku utama, kokassebagai reduktor, dan kapur sebagai aditif. Ketiga bahan baku tersebut dileburhingga mencapai temperatur 1500 oC. Untuk mengetahui kualitas bahan baku danproduk FeMn yang dihasilkan, dilakukan analisa seperti XRF (X-RayFluoroscence), XRD (X-Ray Diffraction), AAS (Atomic Absorbtion Spectrometry),dan Proksimat.Dari hasil penelitian didapatkan bahwa untuk percobaan [1] diperolehlogam FeMn sebanyak 5,2 Kg dengan kadar 54,05 %Mn, percobaan [2] diperolehlogam FeMn sebanyak 4,75 Kg dengan kadar 50,03 %Mn, percobaan [3] diperolehlogam FeMn sebanyak 4,6 Kg dengan kadar 36,44 %Mn, percobaan [4] diperolehlogam FeMn sebanyak 4,3 Kg dengan kadar 31,13 %Mn, dan percobaan [5]diperoleh logam FeMn sebanyak 12,8 Kg dengan kadar 75,19 %Mn. Pengaruh dariproses pencampuran (Mn-blend) dalam pembuatan ferromangan ini adalahsemakin banyak komposisi bijih Mn kadar menengah (MG) yang digunakan,menyebabkan (a) semakin banyaknya kokas dan semakin berkurangnya kapur yangdibutuhkan, (b) meningkatnya yield, jumlah produk, serta kandungan persentaseMn dari FeMn yang dihasilkan, dan (c) semakin rendahnya konsumsi energi yangdibutuhkan.ABSTRACT The potential reserve of manganese ore in Indonesia is very large, but itwas located in different locations spread throughout Indonesia. Manganese ore isone of raw material in producing ferromanganese that is not replaceable in theworld steel industry. Ferromanganese (FeMn) is an alloying metal that containedof 75% Manganese (Mn) and 25% Iron (Fe) which is generally used in the processof iron/steel making to improve its mechanical properties.In this experiment, ferromanganese production was conducted by blendingtwo kinds of manganese ore, that was low grade Mn ore (LG) which derived fromTanggamus, Lampung (16,3 %Mn-19,2 %Fe-20,2 %Si) and medium grade Mn ore(MG) which derived from Jember, East Java (27,7 %Mn-4,4 %Fe-14,7 %Si), toobtain ferromanganese with a minimum content of 50 %Mn. The composition ofMn-blend in this experiment was [1] 25 %LG+75 %MG, [2] 50 %LG+50 %MG,[3] 75 %LG+25 %MG, [4] 100 %LG, and [5] 100 %MG. This mixed manganeseore was processed by using Submerged Arc Furnace (SAF). Cokes and limestonewas added into the furnace as reductant and flux agent, respectively. Those rawmaterials are smelted until 1500 °C. To determine the composition of raw materialsand the product of FeMn, analysis such as XRF (X-Ray Fluorescence), XRD (XRayDiffraction), AAS (Atomic Absorption Spectrometry), and proximate have to bedone.From each composition of Mn-blend above in this experiment, it wasobtained that [1] 5,2 Kg of FeMn with 54,05 %Mn, [2] 4,75 Kg of FeMn with 50,03%Mn, [3] 4,6 Kg of FeMn with 36,44 %Mn, [4] 4,3 Kg of FeMn with 31,13 %Mn,and [5] 12,8 Kg of FeMn with 75,19 %Mn. The effect of Mn-blend in thisferromanganese production was by the increasing composition of the mediumgrade manganese ore (MG) that will cause: (a) the increasing number of cokes andthe decreasing of limestone required, (b) the increasing of yield, the number ofproducts, and also the percentage of manganese content FeMn, and (c) thedecreasing of energy consumption required., The potential reserve of manganese ore in Indonesia is very large, but itwas located in different locations spread throughout Indonesia. Manganese ore isone of raw material in producing ferromanganese that is not replaceable in theworld steel industry. Ferromanganese (FeMn) is an alloying metal that containedof 75% Manganese (Mn) and 25% Iron (Fe) which is generally used in the processof iron/steel making to improve its mechanical properties.In this experiment, ferromanganese production was conducted by blendingtwo kinds of manganese ore, that was low grade Mn ore (LG) which derived fromTanggamus, Lampung (16,3 %Mn-19,2 %Fe-20,2 %Si) and medium grade Mn ore(MG) which derived from Jember, East Java (27,7 %Mn-4,4 %Fe-14,7 %Si), toobtain ferromanganese with a minimum content of 50 %Mn. The composition ofMn-blend in this experiment was [1] 25 %LG+75 %MG, [2] 50 %LG+50 %MG,[3] 75 %LG+25 %MG, [4] 100 %LG, and [5] 100 %MG. This mixed manganeseore was processed by using Submerged Arc Furnace (SAF). Cokes and limestonewas added into the furnace as reductant and flux agent, respectively. Those rawmaterials are smelted until 1500 °C. To determine the composition of raw materialsand the product of FeMn, analysis such as XRF (X-Ray Fluorescence), XRD (XRayDiffraction), AAS (Atomic Absorption Spectrometry), and proximate have to bedone.From each composition of Mn-blend above in this experiment, it wasobtained that [1] 5,2 Kg of FeMn with 54,05 %Mn, [2] 4,75 Kg of FeMn with 50,03%Mn, [3] 4,6 Kg of FeMn with 36,44 %Mn, [4] 4,3 Kg of FeMn with 31,13 %Mn,and [5] 12,8 Kg of FeMn with 75,19 %Mn. The effect of Mn-blend in thisferromanganese production was by the increasing composition of the mediumgrade manganese ore (MG) that will cause: (a) the increasing number of cokes andthe decreasing of limestone required, (b) the increasing of yield, the number ofproducts, and also the percentage of manganese content FeMn, and (c) thedecreasing of energy consumption required.] |