Department of Materials and Metallurgical Engineering, FTI-ITS(*) Sungging PintowantoroDepartment of Materials and Metallurgical Engineering, Faculty of Industrial Technology (FTI),Sepuluh Nopember Institute of Technology Surabaya (ITS), Kampus ITS, Keputih Sukolilo, Surabaya 60111, Telp/Fax : 031-5997026

Iron Ore andProcess Agglomerattion

Department of Materials and Metallurgical Engineering, FTI-ITS(*)Overview Steelmaking Process

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Classified of Iron OresIron ores are rocks and minerals most of whose deposites are found in sedimentary rocks. They formed from chemical reactions that combined iron and oxygen in marine and fresh waters. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, deep purple, to rusty red.The most important minerals in these iron ore deposits are magnetite (Fe3O4), hematite (Fe2O3), goethite (FeO(OH)), limonite (FeO(OH).n(H2O)), ilmenite(FeTiO3) , siderite (FeCO3) and Pyrite (FeS2). These iron ores have been mined to produce almost every iron and steel object that we use today - from paper clips to automobiles to the steel beams in skyscrapers.By Minerals

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Classified of Iron OresBy MineralsMineralogical Characteristic of Iron Ores

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Classified of Iron OresBy Harmful ImpuritiesBy harmful impurities (S, P, Cu, Pb, Zn, V, Ti, Co, Ni, Sn, F, As) ratio of content, iron ores can be divided into high-sulfur iron ore, low sulfur iron ore, high phosphorus iron Ore, low phosphorus iron ore and so on.Harmful impurities are often the minerals that we remove from iron ore in the ore production. Sometimes for removing these impurities , some special physical or chemical methods of beneficiation are chosen to filter them.

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Classified of Iron Ores

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Classified of Iron OresBy GradesIron ore is typically classified as High grade (+65% Fe), Medium grade (+62 65% Fe) and Low grade (-62% Fe). Typically, the Integrated Steel Plants(ISPs) use medium/High grade Iron Ore whereas the Sponge Iron plants require only High Grade iron ore, preferably, with +67% Fe.By Ore StructureAccording to the structure, iron ores can be divided into disseminated ore , stockwork disseminated ores, striped ores, banded ore , dense massive ore, breccia ore, the oolite and bean-shaped, kidney-shaped, honeycomb, powdery, earthy oresBy Special Form(i) Lumpy/Fine Ore: Iron Ore is traded in lumps (i.e. sized ore) or in fines. Production/availability of lumps is limited by virtue of the natural occurrence and also because of generation of lot of fines during crushing of large lumps present in the run-of mines (ROM).(ii) Natural pellet: It is a term coined by producers in some Asian counties, to designate sized iron ore used directly in Sponge Iron production.(iii) Blue Dust: Blue Dust is the name given to naturally occurring, extremely friable, high grade Haematite Iron Ore powder.

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Classified of Iron Ores

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Sintering of Iron OreIron sintering plants are associated with the manufacture of iron and steel, often in integrated steel mills. The sintering process is a pre-treatment step in the production of iron, where fine particles of iron ores and in some plants, also secondary iron oxide wastes (collected dusts, mill scale), are agglomerated by combustion. Agglomeration of the fines is necessary to enable the passage of hot gases during the subsequent blast furnace operation.[1]

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Sintering of Iron OreG Zone : 100 0C partially removed moistureF Zone : 350 0C completely removed moisture (drying zone)E Zone : 800 0C expulsion of carbon dioxideD Zone : 800 900 0C reduction take placeC zone : 900 ignition of fuel (coke)combustion take place until reach 1250 1350 0C. (Sintering zone)B Zone : reoxidation take placeA Zone : cooling gas stream

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Sintering of Iron OreFollowing chemical reactions characterize the sintering

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Pelletizing of Iron Ore

Iron ore is upgraded to a higher iron content through concentration. The concentrate must be pelletized in order to feed a blast furnace or a DRI plant.

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Pelletizing of Iron Ore

WhatPellets are indurated, spheres of ore with a high iron content and uniform quality.Pellet plants can produce two varieties of pellets: blast furnace pellets and direct reduction pellets (DR pellets). Blast furnace pellets are used in the coke-based blast furnace process, which is the most common method of producing hot metal (molten iron for steelmaking). Blast furnace pellets are delivered mainly to steel mills.DR pellets are used in the direct reduction processes to produce sponge iron, which is an alternative process route, as an initial stage from iron to steel. The DR process is primarily based on the use of natural gas and has become increasingly common in countries with access to inexpensive natural gas.ProcessThe object of the process is to transform the pelletized concentrate into hardened pellets that can be used as blast furnace feed or direct reduction furnace feed. The transformation is achieved by the traveling grate and kiln. The traveling grate transports the pelletized concentrate through a series of controlled temperature zones to produce a preheated pellet of 800-900C, which is dropped into the rotary kiln. The rotary kiln finishes the induration and is operated at 1200-1350C. The indurated pellets are now dropped into an annular cooler where the pellets are cooled to a suitable temperature for transporting on a belt to load out facilities. The gases from the cooler are recycled to the kiln and the grate, resulting in the Grate-Kiln being the most energy efficient system for producing indurated pellets.

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Pelletizing of Iron Ore

Three Steps for pelletizing of burden material :Preparation of raw material

The large particles must be grinding first (< 0.2 mm).2.Formation of green pelletsFeed materials + fine ores + binders + limestones charged to drums and sparyed with water. The surface tension take place and first agglomerates are formed. The water must layered the feed materials.

Firing of green pellets

Conditioned feed materials

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Pelletizing of Iron Ore

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Pelletizing of Iron Ore

Binding Mechanism of pellets :

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Pelletizing of Iron Ore

Perbedaan antara Sintering dan Pelletizing

NoAspekSinteringPellet1Ukuran feed materialLebih besar dari pellet (0 10 mm)Ukuran halus (

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Briquetting of Iron Ore

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Briquetting of Iron Ore

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

Briquetting of Iron OreBriquettingCold BriquettingTemperature slightly higher than room temperatureHot Briquetting Temperature reach 1000 0C Binding agentOrganic binding (bitumen, molasses, coal)Inorganic binding (Calcium carbonat, hydroxide, ashes)

Department of Materials and Metallurgical Engineering, FTI-ITS(*)

TERIMA KASIH