Lecture No 1 07-01-2013

Course Title: MY-301: Steel Making Processes

Course Teacher: Muhammad Ali Siddiqui, Lecturer

Academic Session: Spring Semester (2013) Batch: 2010-11

Course Plan

TOPICSNO. OF

PERIODS

Introduction, Difference between iron and steel making processes.

An outline of various methods of steelmaking - Physical chemistry of

steel making process

Raw materials for steel making Process; Acid open hearth and basic

open hearth processes. Oxygen Enrichment of fuel Operation, control

of composition and different slag practices.

Principles of operation under different slag practices for steelmaking

by Electric Arc furnace and Induction furnace. Rapid steel making,

Basic oxygen furnaces.

Acid Bessemer. Basic Bessemer. Side blown convertor. L.D.

convertor, Kaldo Rotor- Bottom blown and combined blown

processes of steel making

Mid Test

Deoxidation by Si. Al- Mn etc., Comparison of deoxidising effects of

various deoxidisers. Deoxidation by complex deoxidisers. Vacuum

degassing of steels. Ladle Metallurgy. Concept of clean steel.

Lecture No 1 07-01-2013

Introduction to secondary steel making. Some modern developments

in steel making like ESR VOD and AOD process Pre-treatment of

steels.

Ingot solidification. Killed, semi killed. Rimmed and capped steels.

Ingot defects, their identification and remedial actions

Continuous casting of steel.

Low, medium and high carbon steels.

Alloy Steels

Tool steels and stainless steels.

Applications of Computers in steel making processes

Manganese steels

Free cutting steel

Basis of designing of Steels.

Final Test

Total 45

Lecture No 1 07-01-2013

Sessional Marks Distribution

Activity in Spring Semester Marks Distribution

Attendance No Marks

Total Test = 02

(Each test of 5 No’s)10 No's.

Problems Assignment

Assign During lectures5 No’s.

Working on EAF,BOS,CC

Simulation (Minimum Practice =

30 times per simulation),

False HEAT does not included

(www.steeluniversity.org)

5 + 5 + 5 = 15 No’s.

Total 30

Total Marks = 100 No’s.Sessional Marks = 40 No's.

Final Exams Marks = 60 No's.

Lecture No 1 07-01-2013List of Text Books

1. Introduction to Modern Steel Making by R. H. Tupkary and V. R. Tupkary (2008)

2. The Making, Shaping and Treating of Steel (Steel Making and Refining)

by Richard J. Fruehan, United States Steel Co., American Society for Metals

ISBN-10: 0930767039, ISBN-13: 978-0930767037

3. Modeling of Steelmaking Processes by Dipak Mazumdar, James W. Evans ISBN-10: 1420062433 | ISBN-13: 978-1420062434

4. Secondary Steelmaking: Principles and Applications Ahindra Ghosh ISBN-10:

0849302641 | ISBN-13: 978-0849302640

5. Ironmaking and Steelmaking: Theory and Practice Ahindra Ghosh (Author), Amit

Chatterjee

6. Physical Chemistry of Steel Making by John. F Elliott, ISBN-10: 0-262-55046-6, ISBN-

13: 978-0-262-55046-8

7. A Text Book Of Metallurgical Analysis Author: B C Agarwal P Jain and S C Sharma

ISBN: 8174091351

Useful Link

www.steeluniversity.orgMake your own Notes it will be easy to understand any subject/topic

Lecture No 1 07-01-2013

MY-301: STEEL MAKING PROCESSES

INTRODUCTION:

What is steel?

Difference between iron and steel making processes?

Engineering practice of the reduction of Iron oxide

1) Reduction of Iron Oxide in Blast furnace by (Indirect Method):

2) Reduction of Iron Oxide in Shaft or Rotary Furnace by (Direct

Method) or MIDREX® Process

Lecture No 1 07-01-2013

1)BLAST FURNACE by (indirect method)

Iron is extracted from the ore haematite (Fe2O3) by reduction CO is a reducing agent because it is more reactive than iron

Process or steps or (how iron is extracted from their ore)

Lecture No 1 07-01-2013

Hot air is blasted into the furnace causing coke (carbon) to burn rapidly and raise the temperature to 2000 °C. (Exothermic reaction) C(s) +    O2 (g)             CO2 (g)     + Heat     

The carbon dioxide then reacts with hot carbon to form carbon monoxide. CO2 (g) +    C(s)             2CO (g) Carbon monoxide then reduces iron in the ore to iron metal. 3CO (g)       +      Fe2O3(s)                3CO2 (g)     +     2Fe (l)

The main impurity is silica (sand or rock) which is SiO2

SiO2 is solid at the furnace temperature and the furnace would become blocked if it was not removed

Limestone is calcium carbonate (CaCO3) and it is added to the blast furnace to remove the impurities in the iron ore.

Calcium carbonate is decomposed by heat in the furnace to give calcium oxide (lime) and carbon dioxide.This is called thermal decomposition.

CaCO3(s)                       CaO(s)        +        CO2 (g)

Silicon dioxide reacts with calcium oxide to form calcium silicate (called slag) which is liquid in the furnace.Slag flows to the bottom of the furnace where it floats on the liquid iron and is easily removed.

  CaO(s)        +         SiO2(s)             CaSiO3 (l)

The slag (CaSiO3) is allowed to cool until it becomes a solidand is used for road construction.

Lecture No 1 07-01-2013

2) Shaft or Rotary Furnace by (Direct Method) or MIDREX®

Lecture No 1 07-01-2013

Reduction:

Iron oxide, in pellet or lump form, is introduced through a proportioning hopper at the top of the shaft furnace.

As the ore descends through the furnace by gravity flow, it is heated and the oxygen is removed from the iron (reduced) by counter flowing gases which have a high H2 and CO content.

These gases react with the Fe2O3 in the iron ore and convert it to metallic iron, leaving H2O and CO2.

For production of cold DRI, the reduced iron is cooled and carburized by counter flowing cooling gases in the lower portion of the shaft furnace.

The DRI can also be discharged hot and fed to a briquetting machine for production of HBI, or fed hot, as HDRI, directly to an EAF.

Reaction in Reformer:CH4 + CO2 2CO + 2H2 CH4 + H2O CO + 3H2 Reaction in shaft Furnace:Fe3O4 + CO 3FeO + CO2 Fe3O4 + H2 3FeO + H2O FeO + CO Fe + CO2 FeO + H2 Fe + H2O