Analisis Pengaruh Distribusi Temperatur Terhadap Proses Degradasi High-Alumina Brick Pada Roof Electric Arc Furnace Di Industri Nikel

Ramadhani, Difa Rifky (2025) Analisis Pengaruh Distribusi Temperatur Terhadap Proses Degradasi High-Alumina Brick Pada Roof Electric Arc Furnace Di Industri Nikel. Other thesis, Institut Teknologi Sepuluh Nopember.

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Abstract

Indonesia memiliki kekayaan bijih nikel laterit yang melimpah, sehingga pemrosesan nikel melalui metode pirometalurgi menggunakan Electric Arc Furnace (EAF) menjadi strategi yang penting dalam industri metalurgi nasional. Namun, salah satu tantangan utama dalam operasi EAF adalah kerusakan pada bagian atap tungku yang dilapisi material refractory high alumina. Material ini bekerja dalam kondisi termal ekstrem yang dapat memicu degradasi mikrostruktur dan retak akibat tegangan termal berulang. Penelitian ini bertujuan untuk menganalisis pengaruh distribusi temperatur terhadap ketahanan material refraktori pada atap tungku EAF melalui simulasi perpindahan panas berbasis computational fluid dynamics (CFD) menggunakan ANSYS Fluent, dan mencakup metode eksperimen. Geometri tungku dimodelkan dengan tinggi 7 m dan diameter dalam 18 m. Kondisi batas temperatur tetap pada kondisi operasi yang berjalan, diasumsikan terjadi konveksi dan radiasi menuju refractory roof. Simulasi dilakukan pada material high-alumina pada antarmuka bagian dalam (inside), luar (outside), dan bagian transisi dengan variasi kondisi operasional dan temperatur operasional. Hasil simulasi ANSYS menunjukkan adanya gradien suhu dari ~845–1049℃ (hot-face) hingga ~720–724℃ (cold-face). Ketidakteraturan distribusi temperatur berpotensi memicu kerusakan struktural, khususnya pada area delta roof. Gradien tersebut menciptakan tegangan termal internal akibat perbedaan ekspansi termal antar-lapisan dan area, serta dapat mengganggu sistem kestabilan internal material refractory. Kecocokan spasial antara titik kerusakan aktual dan zona suhu ekstrem hasil simulasi membuktikan bahwa distribusi temperatur menjadi faktor kunci dalam penurunan umur refraktori. Zona panas yang terus-menerus terekspos radiasi busur listrik dan lingkungan operasi memicu kerusakan struktural lebih cepat. Dengan demikian, mekanisme degradasi refraktori terjadi secara bertahap melalui sintering tidak merata, redistribusi ionik dalam struktur mullite, oksidasi lokal unsur, yang dipicu dan diperburuk oleh distribusi temperatur yang bervariasi. Oleh karena itu, distribusi temperatur yang tidak merata dapat menjadi salah satu faktor menurunnya ketahanan dan integritas refraktori high-alumina pada atap tungku EAF.
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Indonesia has abundant lateritic nickel ore, making the processing of nickel through pyrometallurgical methods using Electric Arc Furnace (EAF) a vital strategy in the national metallurgy industry. However, one of the main challenges in EAF operations is the damage to the furnace roof, which is lined with high alumina refractory material. This material operates under extreme thermal conditions that can trigger microstructural degradation and cracking due to repeated thermal stresses. This study aims to analyze the effect of temperature distribution on the durability of the refractory material on the EAF furnace roof through heat transfer simulations based on computational fluid dynamics (CFD) using ANSYS Fluent, as well as experimental methods. The furnace geometry is modeled with a height of 7 m and an inner diameter of 18 m. The temperature boundary conditions are fixed at the operational conditions, assuming convection and radiation occur toward the refractory roof. The simulation is conducted on high-alumina material at the inner (inside), outer (outside), and transition interfaces with variations in operational conditions and temperatures. The ANSYS simulation results show a temperature gradient from ~845–1049℃ (hot-face) to ~720–724℃ (cold-face). The irregular temperature distribution potentially triggers structural damage, particularly in the delta roof area. This gradient creates internal thermal stresses due to the differences in thermal expansion between layers and areas, which can disrupt the refractory material’s internal stability system. The spatial correlation between actual damage points and extreme temperature zones from the simulation proves that temperature distribution is a key factor in reducing refractory lifespan. The constantly heated hot zones exposed to arc radiation and the operational environment accelerate structural damage. Thus, the mechanism of refractory degradation occurs gradually through uneven sintering, ionic redistribution in the mullite structure, localized oxidation of elements, which is triggered and exacerbated by the varying temperature distribution. Therefore, non-uniform temperature distribution can be one of the factors contributing to the decrease in the durability and integrity of high-alumina refractories on the EAF furnace roof.

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Computational Fluid Dynamics, Distribusi Panas, Electric Arc Furnace (EAF), High-Alumina Refractory, Computational Fluid Dynamics, Electric Arc Furnace (EAF), Heat Distribution, High-Alumina Refractory.
Subjects:	T Technology > TA Engineering (General). Civil engineering (General) > TA169.5 Failure analysis T Technology > TA Engineering (General). Civil engineering (General) > TA347 Finite Element Method T Technology > TA Engineering (General). Civil engineering (General) > TA357 Computational fluid dynamics. Fluid Mechanics
Divisions:	Faculty of Industrial Technology > Material & Metallurgical Engineering > 28201-(S1) Undergraduate Thesis
Depositing User:	Difa Rifky Ramadhani
Date Deposited:	31 Jul 2025 06:03
Last Modified:	31 Jul 2025 06:03
URI:	http://repository.its.ac.id/id/eprint/125057

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