REFRACTORY ENGINEERING

DEPARTMENT
Induction program
Induction Program Report
Date – 07-11-2022

DATE – 07/11/2022
COKE MAKING

INTRODUCTION TO COKE OVENS 3

Insulation Checker
Bricks Bricks

Alumina
Silicate Silica Bricks for
Bricks Coke Oven and Hot
Blast Stove
Refractory Brick
Fire Clay
Bricks
 BASIC PARAMETERS OF THE COKE
OVENS
COKE OVEN COKE OVEN
PARAMETER
3 4
Type By product Recovery By product Recovery

Supplier MECC- China MECC- China

Capacity 1.5 MTPA 1.9 MTPA

No of Batteries 4 4

No of Ovens 224 288

Height of Coking Chamber 4300mm 4300mm

Avg. Hourly production coke oven, T 172.3 205.5

Coke Period 24 hr 24 hr

Avg. Operating Time, Min 10.5Minute 8.5 Minute

Coke +Tar+ Sulphur+Purified
Products Coke +Tar+ Sulphur+Purified gas
gas
Movable machines
Stamping Fixed machines

6
Parameters Coke oven 5 Present cost of blast furnace
coke - $780 per ton.
Type By Product
Recovery Present local consumers of
Technology M/s SINOSTEEL blast furnace coke
Supplier 1. JSW Steel Ltd,
No of Batteries 4 Torangallu, Bellary
No of Ovens 62 per Battery 2. Kirloskar Ferrous
Height of 6.25 mm Industries Ltd,
Battery Hospet
Coke Period 24 hrs 3. Hospet Steels Ltd,
Coke output 33.98 t Hospet.
Coal Charging 42.12 t 4. BMM Ispat,
Per oven Hospet.
Coke Production 3013111 tpa
Per year
7
TORPEDO REPAIR
SHOP (TRS)
 INTRODUCTION

 Torpedo ladles are being used to transfer the molten

pig iron from blast furnace to SMS and the ladle is
used for holding and transporting liquid hot metal.
 An open-topped cylindrical container (Missile
Structured) made of heavy steel plates and lined
with refractory
 The temperature of the hot metal being around 1500
degree Celsius which eventually decreases the life of
these torpedo ladles.
 Due to this erosion cause the refractories need to be
regularly inspected.
 In general its life is about 1300 to 1500 heats.
 A Thermography technique is used to depict the
temperature of the ladle at any given point of time.
 REFRACTORY IN TRS

 Refractory Lining comprises of three major lining

materials
1) Safety – 230mm
2) A1 – Impact Zone – 400mm
3) A2 – 345mm
4) A3 - 340mm

• The torpedo ladle consist of ASC Brick

• The major property of ASC bricks are

1)Excellent Refractoriness under load
2)Excellent Abrasion Resistant Ability
3)Excellent Thermal Shock Performance
4)Spalling resistance and slag corrosion resistance
 SYSTEM OF TRS AT IRON ZONE

• The iron zone consist of 41 Torpedo ladles.

Torpedo Number Capacity

01-26 350 Ton
27-41 380 Ton

• 34 Torpedo’s are under working circulation

• 7 Torpedo’s are under maintenance
• Torpedo’s have minor, mid and 2nd minor repairs
during their 1600 heats cycle.
KANBARA REACTOR [KR]
 KANBARA REACTOR [KR]
o A Kanbara reactor (KR) is a mechanical mixer-type hot metal
desulfurization facility. It is characterized by its acceleration of the
desulfurization reaction through the submersion and rotation of an
impeller in hot metal, and subsequent mechanical mixing of the
hot metal with inexpensive lime as a desulfurizing agent which on
reaction it eliminates calcium sulphate.
o It takes around 15mins for the desulphurization treatment.
o An KR impeller is made to rotate for 15mins at 90rpm by which
the impurity comes out based on density differences.
o Capacity of 1 KR ladle is 140 tons.
o There are in total 16 KR ladles.
o KR have approximately of 1400 temp .
o Around 1500kg lime is used go remove sulfur.
o Wings is of casted of 1.5 ton refractory like OCL refractory castables is dry
mixed for 5 minutes and 5.5 % water is being added and it is being casted .
REFRACTORY USED IN KR

o KR impeller is of Alumina silicon carbide

based refractory because of its high
Thermal shock resistant(TSR) and
Magnesia refractory is not used because
the material handled here is acidic and
MgO being the basic it couldn’t withstand
the acidic material.
BASIC OXYGEN FURNACE (BOF)
BASIC OXYGEN FURNACE

o Basic Oxygen Furnace (BOF) steel making or Basic Oxygen Furnace Steelmaking
(BOS) or Linz-Donawitz.
o A steelmaking method in which pure oxygen is blown into a bath of molten blast-
furnace iron and scrap. The oxygen initiates a series of intensively exothermic
(heat-releasing) reactions, including the oxidation of such impurities
as carbon, silicon, phosphorus, and manganese.
o The vessel consists of three parts: spherical bottom, cylindrical shell and upper cone. The vessel is
attached to a supporting ring equipped with trunnions. The supporting ring provides stable position
of the vessel during oxygen blowing.
o The converter is capable to rotate about its horizontal axis on trunnions driven by electric motors.
This rotation (tilting) is necessary for charging raw materials, sampling the melt and pouring the
steel out of the converter.
o A charge typically consisting of 75–80 percent molten blast-
furnace iron (containing approximately 4 percent carbon), 12–20
percent scrap metal, and lime and other fluxes is fed into the
furnace.
o Inert gas (nitrogen with argon) is injected from the bottom of the
converter to help with the mixing. The basic oxygen furnace uses
no additional fuel.
o The pig iron impurities (carbon, silicon, manganese and
phosphorous) serve as fuel. Indeed, iron and its impurities oxidize
evolving heat necessary for the process.
o Pressurized oxygen is blown in the melting hot metal with a lance, raising the temperature
to 1700°C.
o At this level of temperature, the scrap metal melts, and the content of carbon and of some
other undesirable chemical elements decreases.
o The heat produced by these refining reactions compensates the thermal losses, heats up and
melts all the necessary inputs added and to bring the pig iron to a higher temperature than
the one when it enters the converter.
o The duration of the oxygen “blow,” normally close to 20 minutes, is varied to reduce
the carbon in the steel to the required level. The steel is then tapped into a ladle at
temperatures close to 1,600° C
o In total it is of 45 to 50 mins process.

S.NO STEEL MELTING SHOP CAPACITY (CONVERTER)

1 SMS 1 135 T

2 SMS 2 180 T

3 SMS 3 160 T
The total weight of the refractory in a converter is around
450T.
The refractory used in converter if of Magnesia Carbon
refractory (basic ref) because of its superior slag /metal
corrosion and penetration resistance and excellent thermal
shock properties at high temperatures.
ELECTRIC ARC FURNACE
 ELECTRIC ARC FURNACE
o Electric arc furnace is one of the oldest methods. It has been
used since 1900.
o It is a steel making furnace, in which hot metal, scrap, hot
direct reduced iron, dolomite and lime are heated and melted by
heat of electric arcs striking between the furnace
electrodes(Graphite) and the metal bath.
o The capacity of the EAF is 160T.
o The electricity used is 300 -550kWh/t
o Oxygen is injected through the supersonic injection system as
rate of 2500- 3000 Nm3 for decarburization and Coke is
injected for slag formation.
o The main task of most modern EAFs is to convert the solid raw
materials to liquid crude steel as fast as possible and then refine
further in subsequent secondary steelmaking processes.
PROCESS DIAGRAM
 COMPARISON

S.NO BASIC OXYGEN ELECTRIC ARC FURNACE

FURNACE
1 Main charging Liquid pig iron Solid Scrap, HDRI, Fluxes, Hot metal
2 Scrap ratio 0-30% Up to 100%
3 Alloy content 0-5% 0-100%
4 Final carbon content 0.02-0.03% 0.05-2%
5 Energy input O2 O2,Coke, Electrical energy
6 Refractory lining Basic Basic
7 Cost High Low
 REFRACTORY LINING USED IN EAF
o There are 33 layers in the working lining of the EAF furnace which are made
up of only Magnesia-Carbon bricks
S.NO ZONES LAYERS REFRACTORY USED

1 Metal zone 19
2 Slag zone 12 MgO-C
3 Freeboard 2

o In bottom region, the thickness varies

• Non-impact region -250mm
• Impact region – 300mm
o The bottom ramming mass has a thickness of 850mm

o The side walls of the metal zone has three layers of thickness 476mm
whereas 76mm is safety lining and 400mm is working lining.
 REFRACTORY LINING USED IN EAF
o In backup lining castables are used
S.NO ZONES THICKNESS REFRACTORY
(mm) USED
1 Metal zone 140
2 Slag zone 65 70% Al2O3

3 Below the metal zone 35

(lower region)
o In Safety lining
S.NO ZONES THICKNESS REFRACTORY
(mm) USED
1 Metal zone 65 Alumina
2 Slag zone 35 Chrome Magnesite

3 Below the metal zone 65 Alumina

(lower region)
ZERO POWER FURNACE
 ZERO POWER FURNACE
o The capacity of the ZPF is 190T and the guarantee life is 600 heats.
o The raw materials used are
• CDRI - 30 ton
• Fluxes(dolomite and lime) - 10-12 ton
• Hot metal - 145-150 ton
o The pouring time of the raw materials is 20-25 mins.
o Five supersonic injectors are used to inject oxygen for decarburization in the rate of 4200 Nm3 per injector. It’s
blowing time is 35-40 mins.
o The oxygen is blown in the rate of 2500-3000 Nm3 per hour.
o After 200 heats it will be blown in the rate of 3800-4000 Nm3 per hour.
o The total tapping time is 50 mins with the temperature of 16500C.
o The maintenance time is below 3 mins.
o In this process, deslagging will be done continuously and the slag is removed by paledo.
o The metal present in the slag is separated and the scrap is send to EAF.
REFRACTORY LINING
• Dry ramming mass- 72% of MgO and 13-14% of lime – 498mm thickness
• One layer of bottom working lining – MgO-C bricks of 200mm thickness
• 2 layers of bottom safety lining thickness is 152mm
• The total bottom thickness is 850mm.
• The total sidewall thickness is 526mm(76mm safety lining+450mm working lining)
 STEEL LADLE
• Steel ladle is used to transport steel from converter to
tundish for the casting process. It is moved by cranes, ladle
cars, turntables, or turrets. A ladle turret has two liftable
forks, usually 180° apart, that revolve around a tower, each
fork capable of holding a ladle. Ladles have two heavy
trunnions on each side for crane pickup. Support plates
under each trunnion are used for setting the ladles onto
stands or ladle cars.
• Each ladle has – Purging plug , Slide gate

Capacity – 134T
Guarantee life – 150 heats
It can withstand 110 heats/day
 Refractory Lining
The Ladle can be divided mainly into 3 zones
1. Metal zone
2. Slag zone
3. Free board zone
• Back up casting – 70% Al2O3 contain low cement castable
• Bottom safety – 65% Al2O3 bricks
• Bottom working lining – MgO –C bricks , MgO – 97%, C-10%
• Metal zone safety lining – 42%Al2O3 bricks
• Slag zone safety – Chrome – Mag , MgO – 60% , Cr2O3 – 8%
• Metal zone working – MgO – C bricks , MgO – 97% , C – 10%
• Slag zone working – MgO – C bricks , MgO – 98% , C – 14%
• Free board working – MgO – C bricks , MgO – 97% , C – 10%
 Purging plug
• To achieve homogenous temperature and composition of steel
by fostering of slag metal refining reaction . Argon gas is
purged through bottom purging blocks into the steel bath.
Purging is the most important activitiy in secondary steel
refining process.

Refractory used
L60 refractory
 Slide gate
Slide is used to adjust the flow from the ladle to tundish

Refractory Used
• Well block – Precast shape of Sintered Alumina
• Plate – Alumina-Carbon
• Ladle Nozzle – Precast shape of Sintered Alumina,MA Spinel
• Exchangable Nozzle – Precast shape MA Spinel
• Mortar – Chrome Oxide , Fused Alumina .
 Tundish
Tundishes are containers which are used to feed molten metal into caster moulds. They act as reservoirs
of molten metal that feed continuously the casting process, while ladles are being swapped. Extremely
high temperatures, thermal shock and infiltration of liquid steel and its slags, are the main challenges
imposed on their refractories
Layers of tundish
1)Backup layer
2)Insulation
3)Anchor
4) Refractory – LC 70 Refractory
5)Castables
Capacity – 30 T
Zircon based refractory – stopper
Tundish Process
THANK YOU