Hasil Pencarian  ::  Simpan CSV :: Kembali

"Mineral mangan merupakan salah satu mineral yang paling banyak ditemui di kerak bumi. Sebagian besar produksi mangan dan paduannya di dunia saat ini diserap oleh industri baja. Ferromangan merupakan salah satu logam paduan dengan kandungan mangan yang sangat tinggi, yaitu sekitar 65 - 90%. Sebanyak 90%, ferromangan digunakan untuk menambahkan unsur mangan kedalam material baja untuk memperbaiki sifat-sifat mekanik dari material baja, seperti kekuatan, hardenability, dan ketahanan terhadap aus. Penelitian ini bertujuan untuk mengetahui pengaruh penambahan kadar kokas terhadap keefisienan proses reduksi bijih mangan lokal kadar menengah menjadi produk ferromangan. Proses reduksi dilakukan pada tungku submerged arc furnace tiga fasa dengan kapasitas 100 Kg/Batch dilengkapi dengan tiga buah elektroda grafit. Setiap percobaan menggunakan 30 Kg bijih mangan lokal, 12 Kg limestone, dan kadar kokas yang bervariasi, yaitu 5,5 Kg (18,33%), 7,5 Kg (25,00%), 9,5 Kg (31,67%), dan 11,5 Kg (38,33%). Hasil penelitian menunjukkan bahwa kuantitas dan kualitas produk ferromangan yang dihasilkan meningkat seiring dengan bertambahnya kadar kokas yang digunakan. Dimana kandungan mangan pada ferromangan dan massa/yield produk ferromangan cenderung meningkat. Kandungan mangan pada produk ferromangan tertinggi sebesar 78% pada pengujian menggunakan kokas sebanyak 7,5 Kg (25,00%). Sedangkan massa produk ferromangan tertinggi terdapat pada pengujian dengan menggunakan kokas sebanyak 9,5 Kg (31,67%), yaitu 12,8 Kg. Dan pada penggunaan energi selama proses berlangsung cenderung menurun dengan penambahan kokas, dimana penggunaan energi terendah selama proses reduksi berlangsung pada pengujian menggunakan kokas sebanyak 9,5 Kg (31,67%) sebesar 7,03 KWh/Kg. Namun konsumsi elektroda cenderung meningkat. Sehingga konsumsi elektroda grafit terendah pada saat menggunakan kokas 5,5 Kg (18,33%), yaitu sebesar 0,75 Kg. Berdasarkan aspek ekonomi, pengujian dengan keuntungan tertinggi terdapat pada pengujian menggunakan kokas sebanyak 9,5 Kg (31,67%) yaitu sebesar Rp 62.565 pada tiap satu kali pengujian.

---

Manganese is one of the most common minerals in the earth’s crust.Manganese plays an important role in the development of various steel making processes and its continuing importance is indicated by the fact that about 90% of all manganese alloys consumed annually goes into steel production as an alloying element in the form of ferromanganese. Ferromanganese is one of the metal alloys with a high content of manganese, which is about 65 - 90%. Manganese has four functions to steel such as desulphurizing agent, deoxidation agent, enhancing hardness, and wear resistance. This research, studies have been made to obtain the most optimum raw material composition to produce ferromanganese metal based on local medium grade manganese ore with various amount of cokes as its main variable. The process is conducted four times by smelting manganese ore into ferromanganese metal in mini submerged arc furnace (SAF) technology using three graphite electrodes. The process begin with using 30 kg of medium grade manganese ore from Jember, East Jawa-Indonesia, 12 kg of limestone as its fluxing agent, and various number of cokes from 5,5 kg (18,33%), 7,5 kg (25%), 9,5 kg (31,67%), and 11,5 kg (38,33%). Influence of various amount of cokes being used in this study have been investigated. The experiment conducted by increasing number of cokes carried out good results. Higher consumption of cokes will produce bigger number of ferromanganese metal and also the manganese content inside it. The most optimum composition of cokes shown by this study is 9,5 kg (31,67%), producing the biggest number of product at 12,8 kg of ferromanganese and consuming the least energi at 7,03 kwh/kg FeMn. The other result also showed that adding 7,5 kg (25%) of cokes will produce 78% manganese content inside the metal which was the highest manganese content. However, with an increase of cokes, the electrode consumption will also increase. The experiment with 5,5 kg (18,33%) of cokes carried out the least electrodes consumption at 0,75 kg/process. Moreover, to support the optimum raw material composition, economic evaluation has been conducted. The biggest profit is Rp 62.565,-/process for 9,5 kg (31,67%) of cokes.

"

"[ABSTRAKMangan merupakan logam yang digunakan untuk berbagai macam kebutuhan seperti untuk campuran logam agar menghasilkan baja dalam industri baja. Kebutuhan bijih mangan juga meningkat seiring dengan peningkatan teknologi dan kebutuhan akan mangan tersebut. Pada penelitian ini akan dilakukan proses pembuatan ferromangan dari bahan baku bijih mangan lokal dengan menggunakan submerged arc furnace (SAF). Proses peleburan dilakukan dengan menggunakan 30kg bijih mangan, 12kg batu kapur, dan jumlah kokas serta batu bara yang bervariasi, yaitu 0%, 25%, 50%, 75%, dan 100%. Kemudian, analisa karaktrisasi akan dilakukan untuk mengetahui kualitas produk ferromangan yang dihasilkan, yaitu analisa XRF (X-Ray Fluoroscence), XRD (X-Ray Diffraction) untuk mengecek kadar mangan dan kadar slag, analisa masa selama proses produksi, dan analisa jumlah pemakaian energi selama proses produksi.Hasil penelitian menunjukkan dengan peningkatan kadar kokas dibandingkan kadar batu bara dapat meningkatkan kualitas maupun kuantitas produk ferromangan. Dengan penggunaan 9.5kg (100%) coke akan menghasilkan massa/yield tertinggi yaitu 12.8kg / 96.24% karena kokas memiliki unsur yang lebih baik daripada batu bara sehingga proses reduksi dapat menjadi optimal. Selanjutnya, kandungan mangan pada produk ferromangan tertinggi saat penggunaan 9.5kg (100%) coke sebesar 75.19% Mn karena kokas memiliki kandungan unsur pengotor yang lebih sedikit dibandingkan dengan batu bara sehingga proses reduksi berlangsung dengan optimal. Kemudian, konsumsi energy terendah saat penggunaan 9.5kg (100%) coke sebesar 7.03KWh/kg karena kokas memiliki kandungan pengotor yang sedikit, salah satu contohnya volatile matter, jika kandungan unsur tersebut besar maka konsumsi energi akan bertambah. Sedangkan kandungan fosfor dan sulfur terendah pada produk ferromangan ketika penggunaan 9.5 kg (100%) coke, yaitu fosfor dibawah 0.001% dan sulfur 0.18%. Pengaruh kandungan tersebut berasal dari reduktor yang digunakan, kokas memiliki kandungan phosphorus dan sulphur yang lebih rendah jika dibandingkan dengan kokas. Phosphorus dapat membuat rapuh logam karena adanya perbedaan kekerasan, kekuatan, dan keuletannya. Sedangkan sulphur dapat membuat rapuh logam pada saat temperature tempa, sehingga kemampuan tempanya akan menurun. Selain itu berdasarkan aspek ekonomi, diperoleh hasil yang memilik keuntungan tertinggi sebesar Rp62,565 dengan penggunaanreduktor sebanyak 9.5kg (100%) coke dan 0kg (0%) coal.ABSTRACTManganese mineral is one of the metal element which are used in common to produce alloy steel product. Manganese element is important to enhance steel properties such as wear resistance and hardness. Due to high demand of alloy steel, the production of ferromanganese products are also increase. This phenomena leaded to a large number of manganese ore supply. In this present study, the ferromanganese production will be conducted in mini submerged arc furnace (SAF) technology. The process began with 30 kg medium grade manganese ore from Jember, East Java-Indonesia, 12 kg limestone as its fluxing agent, and with the main variable of mixed reductor from 0%, 25%, 50%, and 100% of cokes and coal as its balance. Along the process, chemical analysis also conducted with some tools to obtain an accurate data of chemical compositions within the raw materials, slag, and ferromanganese product. These chemical analysis were conducted by XRF, XRD, and Proximate analysis. Furthermore, not only the chemical composition but also the number of electricity in each process were calculated to obtain the most efficient process.The result of this research showed an increasing trend in ferromanganese quality and quantity with a large number of cokes. Instead of coal, cokes are more effective as a reductor agent in this process. This study showed that with 9.5 kg of cokes (100%) the reduction process of ferromanganese will produce 12.8 kg of ferromanganese metal, 75.19% of manganese content, 96.24% of yield ratio, and least number of energy consumption 7.03 kwh/kg ferromanganese product. One of the reasons to support this result is because cokes have lesser number of impurities than in coal such as volatile matter. The amount of phosphor and sulfur content in ferromanganese metal also can be reduced to < 0.001% P and 0.18% S by using 100% cokes as its reductor. These parameters are important because with small number of phosphor and sulfur content the metal will become tougher and hinder the negative effect of short red hardness in metal during further forming activity. The other reason to support the effectiveness of using 100% cokes as the reductor instead of mixing with coal is the amount of profit for each process which is turned to be the highest profit number compare to other mixing composition, it is Rp 62.565,-/process., Manganese mineral is one of the metal element which are used in common to produce alloy steel product. Manganese element is important to enhance steel properties such as wear resistance and hardness. Due to high demand of alloy steel, the production of ferromanganese products are also increase. This phenomena leaded to a large number of manganese ore supply. In this present study, the ferromanganese production will be conducted in mini submerged arc furnace (SAF) technology. The process began with 30 kg medium grade manganese ore from Jember, East Java-Indonesia, 12 kg limestone as its fluxing agent, and with the main variable of mixed reductor from 0%, 25%, 50%, and 100% of cokes and coal as its balance. Along the process, chemical analysis also conducted with some tools to obtain an accurate data of chemical compositions within the raw materials, slag, and ferromanganese product. These chemical analysis were conducted by XRF, XRD, and Proximate analysis. Furthermore, not only the chemical composition but also the number of electricity in each process were calculated to obtain the most efficient process.The result of this research showed an increasing trend in ferromanganese quality and quantity with a large number of cokes. Instead of coal, cokes are more effective as a reductor agent in this process. This study showed that with 9.5 kg of cokes (100%) the reduction process of ferromanganese will produce 12.8 kg of ferromanganese metal, 75.19% of manganese content, 96.24% of yield ratio, and least number of energy consumption 7.03 kwh/kg ferromanganese product. One of the reasons to support this result is because cokes have lesser number of impurities than in coal such as volatile matter. The amount of phosphor and sulfur content in ferromanganese metal also can be reduced to < 0.001% P and 0.18% S by using 100% cokes as its reductor. These parameters are important because with small number of phosphor and sulfur content the metal will become tougher and hinder the negative effect of short red hardness in metal during further forming activity. The other reason to support the effectiveness of using 100% cokes as the reductor instead of mixing with coal is the amount of profit for each process which is turned to be the highest profit number compare to other mixing composition, it is Rp 62.565,-/process.]"

"[ABSTRAKPotensi 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.ABSTRACTThe 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.]"

"[Kurangnya penguasaan teknologi pengolahan bijih mangan menjadi ferromangan merupakan salah satu penyebab tingginya impor ferromangan yang dilakukan oleh industri baja nasional. Kualitas produk ferromangan dan juga pencapaian konsumsi energi listrik yang effisien per Kg ferromangan yang dihasilkan menjadi faktor penting pengembangan teknologi ini. Jumlah batubara sebagai reduktor merupakan salah satu parameter utama kesuksesan produksi yang nantinya akan dilihat berdasarkan kualitas FeMn (Kadar Mn hingga 75%) dan seberapa besar power consumption-nya. Pada penelitian ini akan dilakukan proses pembuatan ferromangan dari bahan baku bijih mangan local dengan menggunakan SAF (Submerged Arc Furnace). Variabel yang akan dipakai adalah jumlah batubara sebagai reduktor, yaitu 40.33%, 47%, 53.67%, dan 60.33%. Karakterisasi produk menggunakan XRF (input dan ouput produk), XRD (Mn Ore), dan Proksimat analisis (batubara).Hasil penelitian menunjukan dengan kenaikan jumlah reduktor maka massa produk, kadar mangan, yield product, massa off gas, konsumsi energi, dan persentase fosfor dan sulfur akan meningkat pula. Jumlah produk ferromangan tertinggi didapat pada angka 9.1 kg dengan menggunakan batubara 53.67%. kadar Mn tertinggi didapat pada angka 72% dengan pemakaian batubara 53.67% dan kadar terkecil yaitu 63.12% dengan pemakaian batubara 40.33%. Off gass tertinggi pada angka 33.5 kg dengan pemakaian batubara 60.33% menunjukkan proses reduksi yang tidak optimal, dimana proses reduksi tidak berjalan sempurna. Energi yang paling tinggi di dapatkan pada berat batubara 40.33% yaitu 12.45 Kwh/Kg FeMn, sedangkan yang paling optimum dari segi energi, yaitu didapatkan pada berat batubara 47% dengan 7.56 Kwh/Kg FeMn. %P yang paling tinggi dengan pemakaian batubara 53.67% dengan hasil 0.74% fosfor. Sedangkan untuk %S yang paling tinggi dengan pemakaian batubara 16.1 Kg dengan hasil 0.9% sulfur. Batubara dengan persentase 47% merupakan yang paling optimum apabila dilihat dari aspek ekonomi, %P %S, konsumsi energi, dan kadar mangan.;Due to lack of knowledge and capability to develop new technology for reduction of ferromanganese metal, the number of imported ferromanganese are also increasing in Indonesia. This present study will carried out new perspective to produce ferromanganese metal from Indonesian local manganese ore itself to maintain the demand of ferromanganese product for local industries. The experiment will based on medium grade manganese ore from Jember, East Java ? Indonesia and using mini submerged arc furnace (SAF) as its technology to reduce manganese ore into ferromanganese metal. Influence of various number of coal as its reductor agent have been ninvestigated. The optimized parameter has been established to obtain maximum yield. The experiments with 30 kg of manganese ore, 12 kg of limestone, and various number of coal ranging from 40.33%, 47%, 53.67%, and 60.33% have been carried out. The efforts have also been made to reduce the electrical consumption and the cost of production by using coal instead of cokes.The result showed that an increase in number of reductor increases the amount of product, manganese content, yield ratio, mass of offgas, energy consumption, phosphorus and sulfur content. Biggest number of ferromanganese which can be produced is 9.1 kg with 72% manganese content inside the metal from 53.67% coal and the smallest manganese content is 63.12%Mn from 40.33% coal. Biggest number of off gasses is 33.5 kg which came from 60.33% coal and this phenomena showed that reduction process is not efficient. Highest energy consumption came from 40.33% coal which is 12.45 kwh/kg FeMn product, and the most efficient energy is produced by 53.67% coal which is 7.56 kwh/kg FeMn product. Biggest phosphorus and sulfur content came from 53.67% coal which is 0.74%P and 0.9%S. As the last result, the most optimum research has been carried out by 47% of coal.;Due to lack of knowledge and capability to develop new technology for reduction of ferromanganese metal, the number of imported ferromanganese are also increasing in Indonesia. This present study will carried out new perspective to produce ferromanganese metal from Indonesian local manganese ore itself to maintain the demand of ferromanganese product for local industries. The experiment will based on medium grade manganese ore from Jember, East Java ? Indonesia and using mini submerged arc furnace (SAF) as its technology to reduce manganese ore into ferromanganese metal. Influence of various number of coal as its reductor agent have been ninvestigated. The optimized parameter has been established to obtain maximum yield. The experiments with 30 kg of manganese ore, 12 kg of limestone, and various number of coal ranging from 40.33%, 47%, 53.67%, and 60.33% have been carried out. The efforts have also been made to reduce the electrical consumption and the cost of production by using coal instead of cokes.The result showed that an increase in number of reductor increases the amount of product, manganese content, yield ratio, mass of offgas, energy consumption, phosphorus and sulfur content. Biggest number of ferromanganese which can be produced is 9.1 kg with 72% manganese content inside the metal from 53.67% coal and the smallest manganese content is 63.12%Mn from 40.33% coal. Biggest number of off gasses is 33.5 kg which came from 60.33% coal and this phenomena showed that reduction process is not efficient. Highest energy consumption came from 40.33% coal which is 12.45 kwh/kg FeMn product, and the most efficient energy is produced by 53.67% coal which is 7.56 kwh/kg FeMn product. Biggest phosphorus and sulfur content came from 53.67% coal which is 0.74%P and 0.9%S. As the last result, the most optimum research has been carried out by 47% of coal., Due to lack of knowledge and capability to develop new technology for reduction of ferromanganese metal, the number of imported ferromanganese are also increasing in Indonesia. This present study will carried out new perspective to produce ferromanganese metal from Indonesian local manganese ore itself to maintain the demand of ferromanganese product for local industries. The experiment will based on medium grade manganese ore from Jember, East Java – Indonesia and using mini submerged arc furnace (SAF) as its technology to reduce manganese ore into ferromanganese metal. Influence of various number of coal as its reductor agent have been ninvestigated. The optimized parameter has been established to obtain maximum yield. The experiments with 30 kg of manganese ore, 12 kg of limestone, and various number of coal ranging from 40.33%, 47%, 53.67%, and 60.33% have been carried out. The efforts have also been made to reduce the electrical consumption and the cost of production by using coal instead of cokes.The result showed that an increase in number of reductor increases the amount of product, manganese content, yield ratio, mass of offgas, energy consumption, phosphorus and sulfur content. Biggest number of ferromanganese which can be produced is 9.1 kg with 72% manganese content inside the metal from 53.67% coal and the smallest manganese content is 63.12%Mn from 40.33% coal. Biggest number of off gasses is 33.5 kg which came from 60.33% coal and this phenomena showed that reduction process is not efficient. Highest energy consumption came from 40.33% coal which is 12.45 kwh/kg FeMn product, and the most efficient energy is produced by 53.67% coal which is 7.56 kwh/kg FeMn product. Biggest phosphorus and sulfur content came from 53.67% coal which is 0.74%P and 0.9%S. As the last result, the most optimum research has been carried out by 47% of coal.]"

"[ABSTRAKLogam ferromangan adalah salah satu unsur paduan penting pada bajauntuk meningkatkan sifat mekanis, ketahanan aus, dan kekerasannya. Bentukferromangan (FeMn) telah diatur dalam standard ASTM dengan kadar minimalsebesar 75% Mangan (Mn). Tujuan penelitian ini adalah pembuatan logam FeMndengan kandungan minimal 60%Mn dari bijih mangan lokal dan mempelajari efekdari basasitas terak yang dipengaruhi oleh penambahan kapur sebagai zat aditifdalam proses pembuatan ferromangan terhadap jumlah produk ferromangan yangdihasilkan dan konsumsi energi yang dibutuhkan dalam proses tersebut.Dalam penelitian ini digunakan bijih mangan lokal kadar menengah daridaerah Jember-Jawa Timur 39.38 Mn ? 2.89 Fe ? 26.58 SiO2 (Medium Grade Ore)dengan teknologi Mini Sub-merged Arc Furnace (SAF) di UPT BPM LIPI,Lampung. Setiap satu kali proses, digunakan 30 kg bijih mangan (Ø ±30mm), 7.5kg kokas, dan jumlah batu kapur yang bervariasi, yaitu; 8, 10, 12, dan 14 kg.Proses peleburan berlangsung pada temperatur 1200-1500 oC. Kemudian hasilakan dianalisa dengan menggunakan XRF (X-Ray Fluoroscence), XRD (X-RayDiffraction), AAS (Atomic Absorbtion Spectrometry), dan Proksimat.Hasil penelitian menunjukan bahwa dengan meningkatnya basasitas terak(dari 0.32 hingga 0.76) akan meningkatkan jumlah produk ferromangan hingga 8.2kg FeMn, kemudian memaksimalkan kadar % mangan yang tereduksi pada logamhingga mencapai komposisi kimia yang optimal (78,13 Mn-12,65 Fe-8.93 Si),menekan konsumsi energi hingga 9.8 kwh/kg ferromangan, menekan angkakonsumsi elektroda, dan menghasilkan prosentase efisiensi proses berupa % yieldyang cukup tinggi yakni sebesar 58.61%. Hasil lain yang menunjang prosespengolahan ferromangan dengan meningkatnya hasil basasitas terak adalahtercapainya suhu reaksi yang tinggi yakni sebesar 15940C sehingga membuatreduksi oksida mangan pada terak menjadi mangan pada logam semakin baik,kemudian jumlah terak juga dapat ditekan. Selanjutnya secara tinjauan aspekekonomi dari keempat kali proses penelitian, maka didapatkan hasil yang palingmenguntungkan sebesar Rp 5.731,-/proses.ABSTRACTFerromanganese metal is an important alloying element in steel productionindustry used to maximize its mechanical properties such as wear resistance andhardness. The most common form of ferromanganese according to ASTM standardcontain min.75%Mn and max.25%Fe inside the product. The target of this researchis to obtain ferromanganese metal with min.60%Mn using medium grademanganese ore (39.38 Mn ? 2.89 Fe ? 26.58 SiO2) from Jember district - East Java,yet the effect of its slag basicity will also support the most optimum result. This kindof basicity will determined by the amount of limestone as fluxing agent which addedto the furnace. Moreover, this study will focus to the effect of its slag basicity on thenumber of ferromanganese product and the amoung of energy consumption.This study was taking place at UPT BPM LIPI Lampung, Sumatera. Usingtheir Mini Sub-merged Arc Furnace (SAF) the process began without anybeneficiation processs for its raw material. Manganese ore Ø ±30mm, cokes, andlimestones were added at the same time to the SAF and melted at 1200-1450 oC.Processes were repeated 4 times with each process using 30 kg manganese ore, 7.5kg cokes, and limestones which varied from 8, 10, 12, and 14 kg. Validity of thisstudy supported by the chemical analysis which took place before and afterreduction process using some tools such as XRF (X-Ray Fluoroscence), XRD (XRayDiffraction), AAS (Atomic Absorbtion Spectrometry), and Proxymate analysis.The result of this research showed an increasing trend in product?s qualityas the slag basicity and the amount of limestone increased. As the slag basicityincrease, the number of ferromanganese metal products were also increased until8.2 kg FeMn and the amount of manganese element in metal phase also showed themost optimum chemical composition of ferromanganese metal (78,13 Mn-12,65 Fe-8.93 Si). Furthermore, the energy consumption can be reduced until 9.8kwh/kg FeMn as well as the electrodes consumption and also the efficiencypercentage or % yield process can be increased up to 58.61%. Other parameterswhich used to support these 4-times-research plan was the temperature level whichturned out to be as high as 15940C and helped the reduction process of manganeseoxide into manganese metal became easier. Not only to obtain more manganesecontent in metal phase, but also this level of reduction temperature can reduced theamount of slag. Finally, in addition to support the optimum data, economic analysisalso showed that this composition was the most profitable process with Rp 5.731,-/process as its profit., Ferromanganese metal is an important alloying element in steel productionindustry used to maximize its mechanical properties such as wear resistance andhardness. The most common form of ferromanganese according to ASTM standardcontain min.75%Mn and max.25%Fe inside the product. The target of this researchis to obtain ferromanganese metal with min.60%Mn using medium grademanganese ore (39.38 Mn – 2.89 Fe – 26.58 SiO2) from Jember district - East Java,yet the effect of its slag basicity will also support the most optimum result. This kindof basicity will determined by the amount of limestone as fluxing agent which addedto the furnace. Moreover, this study will focus to the effect of its slag basicity on thenumber of ferromanganese product and the amoung of energy consumption.This study was taking place at UPT BPM LIPI Lampung, Sumatera. Usingtheir Mini Sub-merged Arc Furnace (SAF) the process began without anybeneficiation processs for its raw material. Manganese ore Ø ±30mm, cokes, andlimestones were added at the same time to the SAF and melted at 1200-1450 oC.Processes were repeated 4 times with each process using 30 kg manganese ore, 7.5kg cokes, and limestones which varied from 8, 10, 12, and 14 kg. Validity of thisstudy supported by the chemical analysis which took place before and afterreduction process using some tools such as XRF (X-Ray Fluoroscence), XRD (XRayDiffraction), AAS (Atomic Absorbtion Spectrometry), and Proxymate analysis.The result of this research showed an increasing trend in product’s qualityas the slag basicity and the amount of limestone increased. As the slag basicityincrease, the number of ferromanganese metal products were also increased until8.2 kg FeMn and the amount of manganese element in metal phase also showed themost optimum chemical composition of ferromanganese metal (78,13 Mn-12,65 Fe-8.93 Si). Furthermore, the energy consumption can be reduced until 9.8kwh/kg FeMn as well as the electrodes consumption and also the efficiencypercentage or % yield process can be increased up to 58.61%. Other parameterswhich used to support these 4-times-research plan was the temperature level whichturned out to be as high as 15940C and helped the reduction process of manganeseoxide into manganese metal became easier. Not only to obtain more manganesecontent in metal phase, but also this level of reduction temperature can reduced theamount of slag. Finally, in addition to support the optimum data, economic analysisalso showed that this composition was the most profitable process with Rp 5.731,-/process as its profit.]"

"Cadangan bijih mangan kadar rendah di Indonesia cukup besar, namun cadangan bijih mangan tersebut tidak dapat dimanfaatkan secara optimal karena rendahnya rasio Mn/Fe.Sehingga diperlukan penelitian untuk mempelajari metode benefiasi guna meningkatkan rasio Mn/Fe, menggunakan bijih mangan kadar rendah dari Kabupaten Tanggamus (MnO=15.30%, rasio=0.91) dan kabupaten Jember (MnO=28.66%, rasio=1.39) supaya bisa dijadikan bahan baku dalam pembuatan FeMn menggunakan SAF.Penelitian benefisiasi bijih mangan kadar rendah dimulai dengan melakukan fraksinasi untuk mendapatkan ukuran butir 841-420 μm, 420-250 μm dan 250-177 μm kemudian dilakukan proses pemisahan gravitasi untuk menghasilkan concentrate dan tailing yang akan digunakan sebagai bahan baku untuk reduction reduction roasting. Proses reduction roasting dilakukan dengan variasti suhu 500°C, 700°C dan 900°C serta variasi waktu reduction roasting 30, 60, 90 dan 120 menit dan kemudian dilakukan proses pemisahan secara magnetic. Material non magnetik yang menghasilkan peningkatan rasio Mn/Fe paling optimum akan dilakukan proses briketisasi untuk digunakan sebagai bahan baku pembuatan FeMn menggunakan SAF.Pengaruh variasi temperatur dan waktu reduction roasting memberikan hasil rasio Mn/Fe optimum 6.11, pada partikel non magnetik ukuran 841-420 μm dengan suhu reduction roasting 700°C selama 60 menit. Proses reduction roasting juga menyebabkan munculnya fase baru seperti Hausmanite (Mn3O4), Manganosite (MnO), Fayalite (Fe2SiO4) dan Phlogopite (KMg3(AlSi3O10(OH)2), akibat proses perubahan fase pada bijih mangan. Fase mineral tersebut muncul pada reduction roasting variasi waktu 60 menit, 90 menit dan 120 menit, serta muncul pada variasi suhu 500°C, 700°C dan 900°C.Pada pengujian dalam SAF digunakan basisitas berdasarkan stoichiometri dengan nilai 1.17, 1.32, 1.15 dan basisitas referensi hasil penelitian Bobby et al, 2015, dengan nilai 0.7. Penggunaan basisitas 0.7 menghasilkan kenaikan berat metal dan menurunkan berat terak pada saat diproses dalam SAF. Selain itu basisitas stoichiometry hanya menghasilkan ferromangan dengan Mn=35.47% dan basisitas referensi 0.7 menghasilkan Ferromangan dengan Mn=60%.Hasil penelitian ini menunjukkan bahwa peningkatan rasio menggunakan benefisiasi bisa mencapai rasio 6.11. Sedangkan proses pembuatan FeMn dengan menggunakan bijih mangan kadar rendah pada submerged arc furnace bisa menghasilkan kadar Mn 60% dengan kontrol pada basisitas untuk mengurangi volume terak, meningkatkan berat logam dan menaikkan kadar Mn.

---

Low grade manganese ore reserves in Indonesia is quite large, but manganese ore reserves can not be used optimally because of the low ratio of Mn / Fe.In that case, research is needed to study the methods of benefiasiation to increase the ratio of Mn / Fe, using low grade manganese ore from Tanggamus ( MnO = 15.30% ratio = 0.91) and Jember (MnO = 28.66%, ratio = 1.39) that can be used as raw material in the manufacture of FeMn using SAF.

Research for beneficiation of low grade manganese ore started by fractionation to obtain the grain size of 841-420 μm, 420-250 μm dan 250-177 μm then performed meja getar process to produce the concentrate and tailings to be used as ingredients raw for reduction roasting. Reduction roasting variety process carried out with a temperatur of 500 °C, 700 °C and 900 °C and roasting time variation of 30, 60, 90 and 120 minutes and then a magnetic separation process. Non-magnetic material that produces an increase in the most optimum ratio of Mn/Fe will be used into bricketing process as raw material for FeMn using SAF.

The effect of variation of temperatur and roasting time results ratio of Mn/Fe optimum 6.11, on a non-magnetic particle size of 841-420 μm with a roasting temperature of 700 °C for 60 minutes. Roasting also cause new phase occurensces such as Hausmanite (Mn3O4), Manganosite (MnO), Fayalite (Fe2SiO4) and Phlogopite (KMg3(AlSi3O10(OH)2), due to the process of phase changes in manganese ore. Mineral mineral appeared on roasting with time variations 60 minutes, 90 minutes and 120 minutes, as well as appearing on the variation in temperatur of 500 °C, 700 °C and 900 °C.

On testing in the SAF used basicity based stoichiometri with a value of 1.17, 1.32, 1.15 and reference basicity 0.7 based on the Bobby et al, 2015 reserach. Influence of basicity resulted in an increase of weight of metal and decrease the weight of slag during processing in the SAF. In addition basicity stoichiometry produces only ferromangan with Mn = 35.47% and reference basicity 0.7 generate Ferromangan with Mn = 60%.

The results of this study showed that increasing the ratio of Mn/Fe using beneficiation could reach a ratio 6.11. While the process of making FeMn using low grade manganese ore at Submerged arc furnace can produce 60% Mn grade with controls on basicity to reduce the volume of slag, improve and raise the level of heavy metals Mn."

"Indonesia sebagai negara kepulauan memiliki potensi besar dalam industri besi dan baja. Maka dari itu potensi Indonesia di industri besi dan baja harus dikembangkan untuk meningkatkan perekonomian masyarakat. Sehingga diperlukan teknologi untuk memanfaatkan potensi yang ada. Tanur putar merupakan salah satu contoh teknologi yang dapat digunakan. Pada tanur putar terjadi reduksi langsung bijih besi bongkah menjadi besi spons. Proses reduksi langsung dilakukan dengan menggunakan reduktor arang batok kelapa. Pada proses reduksi langsung terdapat parameter-parameter yang mempengaruhi reduksi langsung salah satunya adalah ukuran bijih besi yang digunakan.Penelitian ini dilakukan untuk mengetahui pengaruh ukuran bijih, ukuran bijih yang digunakan adalah 1 cm, 2 cm, dan 3 cm. Hasil reduksi diuji dengan menggunakan XRD (X-Ray Diffraction). Hasil menunjukkan bahwa terjadi reduksi dari Fe2O3 menjadi Fe3O4 dan bijih berukuran 1 cm merupakan bijih yang mengalami reduksi paling optimal. Dapat disimpulkan bahwa bijih 1 cm merupakan ukuran yang paling optimal untuk proses reduksi langsung.

---

Indonesia as an archipelago has great potential in the iron and steel industry. Thus the potential in the iron and steel industry should be developed to improve the community's economy. A necessary technology needed to exploit the potential. Rotary kiln is one technology that can be used. Inside, direct reduction occurs reducing lump ores into sponge irons. Direct reduction process is done using coconut charcoal as a reductant. There are parameters that affect the direct reduction process, one of them is the ore size.

This study was conducted to determine the effect of ore size, ore used is 1 cm, 2 cm, and 3 cm. Reduction results tested using XRD (X-Ray Diffraction). The results showed that reduction occurs, reducing of Fe2O3 into Fe3O4 and 1 cm-sized ore is the optimally reduced ore. It can be concluded that the ore 1 cm is the optimal size for the direct reduction process."

"Aluminium paduan seri 5083 banyak digunakan pada aplikasi perkapalan karena ketahanan korosinya yang baik di lingkungan laut dan kekuatan spesifik yang baik. Namun pada proses pengelasannya, aluminium sering terdapat porositas di daerah lasannya. Salah satu cara untuk mengurangi porositas dalam pengecoran aluminium adalah dengan memberikan getaran saat pengecoran dilakukan dan ini coba diterapkan pada pengelasan aluminium. Hasil penelitian tidak menunjukkan pengaruh yang berarti pada jumlah porositas yang terbentuk. Untuk nilai rata-rata uji tarik yang tertinggi terdapat pada spesimen yang tidak digetarkan, dengan nilai 231 Mpa. Sedangkan nilai rata-rata kekerasan tertinggi pada weld metal terdapat pada spesimen yang digetarkan dengan nilai 81,68 HVN.

---

Aluminum alloy 5083 series is widely used in marine applications due to good corrosion resistance in marine environments and good specific strength. But in the process of welding, porosity is often found in the weldment of aluminum. One way to reduce porosity in the aluminum casting is to provide a vibration when casting is performed so it is trying to be applied to the welding of aluminum. The results of the study showed no significant effect on the amount of formed porosity. The highest average value of tensile strength is in the specimens that are not vibrated, with a value of 231 MPa. While the highest average value of hardness in weld metal is in the specimens that vibrated with a value of 81.68 HVN."

"ABSTRAKBatasan rasio komposisi Cu : Mg yang mengalami fenomena rapid hardening pada paduan Al-Cu-Mg masih belum diketahui secara pasti. Selain itu juga, pengaruh komposisi Cu dan Mg pada rentang yang lebar terhadap respons penuaan belum pernah diamati dengan rinci. Penelitian ini mengamati pengaruh variasi komposisi Cu dan Mg pada fenomena rapid hardening dan respons penuaan pada paduan Al-Cu-Mg. Karakterisasi meliputi pengujian kekerasan Vickers dan pengamatan mikrostruktur dengan menggunakan mikroskop optik, SEM/EDS (Scanning Electron Microscopy/Energy Dispersive Spectroscopy), dan TEM (Transmission Electron Microscopy). Hasil menunjukkan bahwa peningkatan komposisi Cu dan Mg memperkecil ukuran butir dan meningkatkan fraksi volume partikel intermetalik yang terbentuk. Pada rentang komposisi Cu (1.1-3.0 at.%) dan Mg (1.7-3.5 at.%) yang lebar, pada paduan Al-Cu-Mg, batas rasio terjadinya fenomena rapid hardening belum dapat ditentukan dengan tepat. Komposisi dimana terjadi fenomena rapid hardening pada penuaan temperatur 170 oC ternyata fluktuatif. Pada saat rapid hardening (waktu penuaan 60 detik), loop dislokasi merupakan satu-satunya mikrostruktur yang ditemukan, sementara pada saat kekerasan puncak, ditemukan presipitat fasa S.

---

ABSTRACTThe range of Cu : Mg ratio in Al-Cu-Mg alloy which undergoes rapid hardening has not been clearly understood. The ageing response on this alloy with wide Cu : Mg ratio has not been fully evaluated. This study observed the effect of Cu : Mg ratio on rapid hardening and ageing response of Al-Cu-Mg alloys. Characterization included Vickers Hardness Testing and Microstructural Observation by using Optical Microscope, SEM/EDS (Scanning Electron Microscopy/Energy Dispersive Spectroscopy), and TEM (Transmission Electron Microscopy). The results showed that the higher the Cu and Mg content, the smaller the grain size and the higher the volume fraction of intermetallic particles. Within the range of 1.1-3.0 at.% Cu and 1.7-3.5 at.% Mg, the Cu : Mg ratio at which rapid hardening occurred, was not able to define. The data was fluctuative at the ageing temperature of 170 oC. After rapid hardening (for 60 seconds of ageing), dislocation loops were observed. While at the peak hardness, the microstructure was strengthened by S precipitates."

"ABSTRAKPenggunaan baja sebagai material konstruksi menuntut setiap negara mengeluarkan peraturan desain. Di Indonesia regulasi perhitungan struktur baja tertuang dalam SNI 03-1729-2002. Untuk mempermudah para perencana melakukan preliminary desain, SNI baja perlu dilengkapi dengan tuntunan praktis dalam bentuk grafik atau tabel seperti halnya AISC. Penelitian ini bertujuan melengkapi SNI baja Indonesia dengan grafik kuat tekan kolom baja sebagai fungsi dari panjang efektif dengan asumsi kolom berada pada braced frame. Dilakukan pengembangan grafik penentuan kapasitas nominal kolom untuk profil WF dan H yang diproduksi oleh salah satu produsen baja di Indonesia. Menggunakan bantuan software Matlab, output dari program diplot dalam bentuk grafik dan tabel hubungan antara panjang efektif kolom dan kapasitas nominal. Dilakukan validasi terhadap output program dengan AISC, besarnya deviasi perhitungan berkisar antara 0,001 % - 1%.

---

ABSTRACTThe use of steel as structural components should follow design code released by government in each country. Indonesia design regulation of steel as a buliding structure is described in SNI 03-1729-2002. In order to help structural designer to predict nominal capacity of column and also to choose the suitable profile, SNI should be accomplished with graphs or tables. The research conducted is aimed to produce graph of nominal capacity of several WF and H shapes produced by one of local manufacturing in Indonesia. Matlab was used as programming software. The result is presented in table and graph as a function of effective length (Le) of the column. The program output is being validated againts AISC. Small deviation of 0,001% to 1 % is found. In general, the results are valid an can be used as a complementary of SNI 03-1729-2002."