1st Edition

Agglomeration of Iron Ores

By Ram Pravesh Bhagat Copyright 2019
    438 Pages 172 B/W Illustrations
    by CRC Press

    This book focuses on agglomeration, or the size enlargement process, of iron ores. This process sits at the interface of mineral processing and extractive metallurgy. The book begins with a discussion of raw materials preparation and the beneficiation process. It then describes fundamental principles of the sintering and pelletization processes, including formation of green mix through granulation and green balls as well as chemical reactions during sintering. Finally, it offers a brief description of iron making processes and correlations related to the agglomerates: quality parameters and BF productivity and coke rate.

    Chapter 1: Introduction

    1.1 Preamble

    1.2 Definition and Category

    1.3 Scope of Agglomeration

    1.4 Need for Agglomeration

    1.5 Raw Materials for Agglomeration

    1.6 The Agglomeration Processes

    1.7 Iron-Making

    1.8 R&D

    1.9 Techno-Economics

    1.10 Evolutionary Phases

    Chapter 2: Raw Materials : Characterization and Preparation

    2.1 Categories and Specifications

    2.2 Characterization of Raw Materials

    2.3 Genesis of Iron Ore

    2.4 Classification of Iron Ores

    2.5 Mineralogy of Iron Ores

    2.6 Preparation of Iron Ores

    2.7 Industrial Practice on Iron Ore Beneficiation and Process Flow Sheets

    2.8 Handling of Iron Ores

    Chapter 3: Iron-Making Processes

    3.1 Preamble

    3.2 Reduction of Iron Oxide

    3.3 Direct Reduction Processes

    3.4 Blast Furnace (BF) Iron Making Process

    3.5 Blast Furnace (BF) Iron-Making Reactions

    3.6 Blast Furnace Performance : Factors Affecting

    Chapter 4:: Agglomerates in Iron-Making Processes

    4.1 Preamble

    4.2 Agglomerates in Iron Making Processes

    4.3 Properties of Agglomerates

    4.4 Quantitative Effect on Blast Furnace Performance

    Chapter 5: Process of Sintering

    5.1 Preamble

      1. The Sintering Process
      2. Control of Sinter Plant Operation

    5.4 Pollution Control and Waste Heat Recovery

    5.5 Recycling of Steel Plant Solid Waste

    5.6 Non-conventional / Other Process

    Chapter 6: Sintering Fundamental

    6.1 The Process of Sintering

    6.2 Sintering Zones

    6.3 Air Flow and Permeability

    6. 4 Structure and Porosity of Bed

    6. 5 Granules and Granulation

    6.6 Thermal Characteristics during Sintering

    6.7 Bonding in Sinter

    6.8 Assimilation and Coalescence

    6.9 Sintering Reactions

    6.10 Sintering Reaction and Mineralogy

    6.11 Mass Balance

    6.12 Heat Balance

    6.13 Ignition

    6.14 Combustion of Solid Fuel in Sintering

    Chapter 7: Sinter Productivity: Theoretical Consideration and Plant Practice

    7.1 Sinter Productivity

    7.2 Bed Permeability and Bed Structure

    7.3 Iron Ores: Particle Size and Characteristics

    7.4 Granulation

    7.5 Moisture Content of Sinter Mix

    7.6 Sinter Basicity and MgO Content

    7.7 Coke and Fluxes: Content, Nature and Particle Size

    7.8 Return Fines

    7.9 Sinter Mean Size

    Chapter 8: Sinter Mineralogy

    8.1 Preamble

    8.2 Major Constituents and Desired Mineralogy of Sinter

    8.3 Mineralogical Terminology

    8.4 Sintering Reaction and Mineralogy

    8.5 5 Composition and Mineralogical Characteristics of Fluxed Sinter

    8.6 Process Variables and Sinter Mineralogy

    8.7 Sinter Chemistry and its Mineralogy

    8.8 Sinter Mineralogy and Quality Parameters

    Chapter 9: Sinter Quality: Theoretical Consideration and Plant Practice

    9.1 Sinter Quality and Contributing Factors

    9.2 Sinter Mineralogy and its Quality Parameters

    9.3 Cold Strength

    9.4 Sinter Reducibility

    9.5 Sinter Reduction –Degradation Index (RDI)

    9.6 Salient Ways to Improve Sinter RDI

    Chapter 10: Process and Operational Variables with respect to Sintering

    10.1 Preamble

    10.2 Iron Ore : Characteristics and Size Parameters

    10.3 Alumina Content of Ore

    10.4 Sinter Basicity

    10.5 MgO Content of Sinter

    10.6 Fluxes: Size Parameters, Calcination and Assimilation

    10.7 Solid Fuel

    10.8 Newer Coating and Granulation Techniques

    Chapter 11: Pelletization Process

    11.1 Pelletization Process

    11.2 Raw Materials and their Preparation

    11.3 Pelletization Steps

    11.4 Environmental Pollution and Control

    11.5 Specification of Pelletization Plants

    11.6 Composite Pellets

    Chapter 12: Green Pelletization: Process and Mechanism

    12.1 Balling Process

    12.2 Formation of Green Balls and Growth

    12.3 Strength of Wet Agglomerates

    12.4 Viscosity Effect and Binders

    12.5 Elastic and Plastic Deformation of Green Pellets

    12.6 Stages of Pellet Formation and Growth

    12.7 Kinetics of Ball Growth




    Chapter 13: Quality of Green Pellets

    13.1 Preamble

    13.2 Size and Porosity of Pellets

    13.3 Drop Resistance (Number)

    13.4 Wet Compressive Strength

    Chapter 14: Induration of Green Pellets

    14.1 Preamble

    14.2 Pellet Induration : Steps

    14.3 Process of Induration using Shaft Furnace

    14.4 Straight Grate Process of Pellet Induration

    14.5 Grate-Kiln-Cooler Process

    14.6 Comparison of Straight Grate Process vis-à-vis Grate Kiln Process

    14.7 Factors influencing the Induration Process (and Pellet Quality)

    14.8 Fuel Substitution in Pellet Induration

    Chapter 15: Reactions and Formation of Phases during Induration

    15.1 Preamble

    15.2 Induration of Magnetite bearing Pellets and Phases Formed

    15.3 Induration of Hematite bearing Pellets and Phases formed

    15.4 Induration: Magnetite vis-à-vis Hematite Concentrate

    15.5 Phases and Pores in Indurated Pellets

    15.6 Parameters influencing the Mineral Phases in Indurated Pellets

    15.7 Parameters Influencing the Porosity in Indurated Pellets

    15.8 Duplex Structure

    Chapter 16; Quality of Indurated Pellets

    16.1 Preamble: Pellet Properties and Factors Influencing

    16.2 Pellet Chemistry

    16.3 Bulk Density and Angle of Repose

    16.4 Crushing Strength (CCS)

    16.5 Porosity .

    16.6 Swelling Index

    16.7 Pellet Reducibility

    16.8 Reduction – Degradation Index (RDI)

    16.9 Softening and Melt-Down Characteristics


    Ram Pravesh Bhagat (born October 1954 has 36 years of research experience in the iron ore beneficiation & agglomeration areas while serving premier R&D establishments, SAIL-RDCIS and CSIR-NML.

    He has worked with Soviet Experts to implement R&D Projects at SAIL plants aimed to improve the productivity of sinter and its quality. In the 1990’s, the author research projects in collaboration with IIT Kharagpur, RAS Russia and with support from Private Industries. His subsequent research career in CSIR-NML (2000--2014) had been concentrated to the agglomeration area with support from the Ministry of Steel (Govt, of India), Private/ PSU Organisations,

    As a faculty member of AcSIR-CSIR and IIT (ISM), the author has developed courses in agglomeration technology and delivered invited lectures. He has supervised two Ph.D. scholars (IIT Kharagpur) and four M. Tech students (ISM). At ISM he initiated research in the field of agglomeration. He has contributed three book chapters including "Agglomeration" in the Encyclopedia of Iron, Steel, and Their Alloys (CRC Press). He has also published over a hundred research papers in journals and conference proceeding volumes. He is life fellow and member of several professional bodies. He is also recipient of various awards and fellowship including CSIR-DAAD.

    Agglomeration of Iron Ores covers in considerable detail both the sintering and pelletising of iron ore fines and concentrates that are generated along with lump ore in iron ore mines around the world, either naturally or after upgrading in a beneficiation process. The book is devoted to a detailed treatise of the sintering and pelletising of the raw materials in separate chapters, including the fundamentals, mineralogy, reactions, process and operating variables, quality and productivity of sintering and pelletising. In summary, this book is a masterful coverage of the subject, and is recommended reading for metallurgical students, teachers, researchers, and practicing professionals in the iron and steel industry.

    --Ralph J Holmes, CSIRO Mineral Resources, Clayton, VIC, Australia, Mineral Processing and Extractive Metallurgy, April 2020