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ABSTRAKPotensi cadangan bijih mangan di Indonesia cukup besar, namun terdapat
di berbagai lokasi yang tersebar di seluruh Indonesia. Komoditi ini menjadi bahan
baku 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 memperbaiki
sifak-sifat mekanik dari produk yang dihasilkan.
Penelitian ini dilakukan untuk mempelajari pengaruh proses pencanpuran
bijih 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 berasal
dari Jember, Jawa Timur (27,7 %Mn-4,4 %Fe-14,7%Si) sebagai bahan baku untuk
pembuatan logam FeMn dengan kandungan minimal sebesar 50 %Mn. Penelitian
ini dilakukan sebanyak 5 kali percobaan dengan variasi pada campuran bijih Mn
yaitu [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 Arc
Furnace (SAF) dengan input berupa bijih Mn sebagai bahan baku utama, kokas
sebagai reduktor, dan kapur sebagai aditif. Ketiga bahan baku tersebut dilebur
hingga mencapai temperatur 1500 oC. Untuk mengetahui kualitas bahan baku dan
produk FeMn yang dihasilkan, dilakukan analisa seperti XRF (X-Ray
Fluoroscence), XRD (X-Ray Diffraction), AAS (Atomic Absorbtion Spectrometry),
dan Proksimat.
Dari hasil penelitian didapatkan bahwa untuk percobaan [1] diperoleh
logam FeMn sebanyak 5,2 Kg dengan kadar 54,05 %Mn, percobaan [2] diperoleh
logam FeMn sebanyak 4,75 Kg dengan kadar 50,03 %Mn, percobaan [3] diperoleh
logam FeMn sebanyak 4,6 Kg dengan kadar 36,44 %Mn, percobaan [4] diperoleh
logam 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 dari
proses pencampuran (Mn-blend) dalam pembuatan ferromangan ini adalah
semakin banyak komposisi bijih Mn kadar menengah (MG) yang digunakan,
menyebabkan (a) semakin banyaknya kokas dan semakin berkurangnya kapur yang
dibutuhkan, (b) meningkatnya yield, jumlah produk, serta kandungan persentase
Mn dari FeMn yang dihasilkan, dan (c) semakin rendahnya konsumsi energi yang
dibutuhkan.
ABSTRACTThe potential reserve of manganese ore in Indonesia is very large, but it
was located in different locations spread throughout Indonesia. Manganese ore is
one of raw material in producing ferromanganese that is not replaceable in the
world steel industry. Ferromanganese (FeMn) is an alloying metal that contained
of 75% Manganese (Mn) and 25% Iron (Fe) which is generally used in the process
of iron/steel making to improve its mechanical properties.
In this experiment, ferromanganese production was conducted by blending
two kinds of manganese ore, that was low grade Mn ore (LG) which derived from
Tanggamus, 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), to
obtain ferromanganese with a minimum content of 50 %Mn. The composition of
Mn-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 manganese
ore was processed by using Submerged Arc Furnace (SAF). Cokes and limestone
was added into the furnace as reductant and flux agent, respectively. Those raw
materials are smelted until 1500 °C. To determine the composition of raw materials
and the product of FeMn, analysis such as XRF (X-Ray Fluorescence), XRD (XRay
Diffraction), AAS (Atomic Absorption Spectrometry), and proximate have to be
done.
From each composition of Mn-blend above in this experiment, it was
obtained 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 this
ferromanganese production was by the increasing composition of the medium
grade manganese ore (MG) that will cause: (a) the increasing number of cokes and
the decreasing of limestone required, (b) the increasing of yield, the number of
products, and also the percentage of manganese content FeMn, and (c) the
decreasing of energy consumption required., The potential reserve of manganese ore in Indonesia is very large, but it
was located in different locations spread throughout Indonesia. Manganese ore is
one of raw material in producing ferromanganese that is not replaceable in the
world steel industry. Ferromanganese (FeMn) is an alloying metal that contained
of 75% Manganese (Mn) and 25% Iron (Fe) which is generally used in the process
of iron/steel making to improve its mechanical properties.
In this experiment, ferromanganese production was conducted by blending
two kinds of manganese ore, that was low grade Mn ore (LG) which derived from
Tanggamus, 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), to
obtain ferromanganese with a minimum content of 50 %Mn. The composition of
Mn-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 manganese
ore was processed by using Submerged Arc Furnace (SAF). Cokes and limestone
was added into the furnace as reductant and flux agent, respectively. Those raw
materials are smelted until 1500 °C. To determine the composition of raw materials
and the product of FeMn, analysis such as XRF (X-Ray Fluorescence), XRD (XRay
Diffraction), AAS (Atomic Absorption Spectrometry), and proximate have to be
done.
From each composition of Mn-blend above in this experiment, it was
obtained 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 this
ferromanganese production was by the increasing composition of the medium
grade manganese ore (MG) that will cause: (a) the increasing number of cokes and
the decreasing of limestone required, (b) the increasing of yield, the number of
products, and also the percentage of manganese content FeMn, and (c) the
decreasing of energy consumption required.]