India

Iron Ore Developments – view from a growing mining and steel industry

Ashok Kumar Tata Steel

Jamshedpur, India

IRON ORE 2017 Building Resilience

24th-26th July, 2017

Perth, Australia

1

India

Iron Ore Developments – view from a growing mining and steel industry

Iron ore reserves - local demand, supply, stress

Nature of the iron ore

Alumina – a difficult chapter in Indian BF ironmaking

Beneficiation challenges

Agglomeration developments 2

Iron Ore in India, numbers

resource, reserve, spread, extraction, projection Estimated Resource,

billion t

Extractable Reserve,

billion t

Current extraction,

mtpa

Estimated domestic demand 2025

mtpa

Hematite Odisha

Jharkhand Chattisgarh

Karnataka

Goa

18 5.9 4.6 3.3 2.2 1.0

9.6

Almost all hematite

Based on a projected steel

production of 180-220 mtpa

Largely hematite, some magnetite

could come in

Magnetite Karnataka

Andhra Pradesh Rajasthan

Tamilnadu Assam + others

10.5 7.8 1.5 0.5 0.5 0.3

0.02

total

28.5 9.6 160-200 ~350

3

India major economic iron ore deposits are associated with

BIF and divided into 5 distinctive zones

Zone A Bonai Iron ore Range

Zone B: N-S trending linear belt in central India

Zone C: Bellary Hospet region

Zone D: Goa and West Maharashtra

Zone E: Magnetite deposit of Karnataka

5

Forest Map Tribal population

Iron ore rich area

Mineral rich areas overlap

with areas having :

Dense forest cover Low HDI High Tribal Population Left wing extremism

Mineral Resource – Occurrence vis-à-vis Challenges

6

Distress in Indian iron ore industry – levies

7

8

Disadvantage Indian iron ore industry – scale

250 MT

290 MT

327 MT

Total No of Mines: 9

Total No of Mines: 15

Total No of Mines: 8

Total No of Mines: 6

Total No of Mines: 7

Total No of Mines: 4

17 MT

19 MT

30 MT

~47 m3 ~400 T ~10 m3 ~100 T

1

132

311

363

2013-14 2025-26

Iron Ore Forecast in 2025 mtpa

Steel Forecast in 2025 mtpa

Supply demand balance in 2025 mtpa

87

202

233

2013-14 2025-26

@7% GDP

@8% GDP +146

+231

Required Avialble

350- 400 150-

@7% GDP

@8% GDP

-200

• From being an exporter, India could become a major Importer of iron ore ??

If iron ore mining does not step up pace ..

Will iron ore mining growth keep up with steel ?

Nature of the iron ore

• Reasonably good Fe .. 52-64 %

• Moderate silica .. 2-5%

• Relatively higher alumina .. 1.5-7 % (particularly eastern India ores)

very finely disseminated in the ore- inclusions as small as a few microns

often, incorporated into the mineral lattice – Fe atoms replaced by aluminium atoms in lattice

Nature of iron ore: First impressions can sometimes mislead why eastern India ores are more difficult

Western region ores Eastern region ores

Ore type

Grade, % Fe

Friable, Soft

52-58

Hard, Friable, Blue dust, Soft

58-65

Mineral make up

major…

minor…

Hematite, Goethite

Gibbsite, Kaolinite, Quartz

Hematite, Goethite

Gibbsite, Kaolinite, Quartz

Textural Association Gangue as void filling Gangue as very fine inclusions

Goethite is ocherous

Alumina Deportment

• Alumina mainly contributed by

Gibbsite and Kaolinite (~75%)

• Alumina contributed by Goethite is

low (~25%)

• Al substitution for Fe in Goethite

lattice is 8% max

• Alumina mainly contributed by

Goethite(~65%)

• Alumina contributed by Gibbsite

and Kaolinite (~35%)

• Al substitution for Fe in Goethite

lattice is ~ 18%

the “rising” ore quality dis-advantage

13

0

1

2

3

4

5

6

7

Me

talo

inve

st

-…

Nort

hla

nd

- T

ap

uli

Fee

d

Me

talo

inve

st

-…

Clif

fs -

Wa

bush…

Me

tinve

st

- C

GO

K 6

8%

…

Sydvara

ng

er

- P

rodu

ct

2

LK

AB

- K

PB

A 2

01

2

Me

talo

inve

st

-…

Sydvara

ng

er

- P

rodu

ct

4

Me

tinve

st

- Y

UG

OK

…

Me

tinve

st

- S

evG

OK

…

Me

tinve

st

- In

gG

ok…

Fe

rre

xpo

- P

rem

ium

…

Sa

ma

rco

- P

F

LK

AB

- M

PB

O 2

012

Me

tinve

st

- M

agp

ie…

LK

AB

- M

PF

20

12

Se

ve

rsta

l -…

AM

MC

- B

SN

Pe

llets

Clif

fs -

Wa

bush F

luxe

d…

Rio

Tin

to -

IO

C A

cid

…

Me

tinve

st

- C

GO

K 6

5%

…

Sa

ma

rco

- L

S P

elle

ts

SN

IM -

GM

AB

Sa

ma

rco

- B

F P

elle

ts

Me

talo

inve

st

-…

Ba

min

- D

SO

Lu

mp

Va

le -

PF

FT

20

12

Dufe

rco

- A

cap

ulc

o

Dan

ne

mo

ra -

DL1

6

Va

le -

AS

08

SN

IM -

TZ

FC

Va

le -

AF

50

CS

N -

Nam

isa S

F

SN

IM -

TZ

F

An

glo

- S

ishe

n L

um

p

Ra

na G

rub

er

- H

15

0

Va

le -

IO

CJ 2

01

3

Lon

do

n M

inin

g -

…

Usim

ina

s -

SF

Va

le -

LO

BT

An

glo

- S

ishe

n F

ine

s

CS

N -

SS

H5

Assm

an

g -

Kh

um

an

i…

Va

le -

PF

FG

20

13

An

glo

- S

F5

8

Ta

ta S

teel -

cu

rren

t

BH

PB

- N

ew

ma

n

FM

G -

Ro

cke

t F

ines

Se

sa

Goa

- S

ixty

One %

Ta

ta S

teel -

like

ly f

utu

re

Rio

Tin

to -

Robe

Va

lley

Eld

ora

do -

Vill

a N

ova

…

QIT

- Ilm

en

ite

Afr

ica

n M

ine

rals

-…

Al2

O3,

%

Global Iron Ore Alumina

Ind

ia ..

b

ette

r q

ual

ity

Ind

ia …

ave

rage

0

100

200

300

400

500

600

8 13 18 23

Al2O3%

Vis

cosi

ty

1330

1340

1350

1360

1370

1380

1390

1400

Liqu

idus

Tem

p(C

)

Viscosity

Liquidus Temp

Effect of alumina on viscosity and liquidus temperature BF slag alumina 15 20 % - implications

Blast furnace slag - CaO/SiO2=1 , MgO=7%, 1500 oC

constant alumina input

Liquidus ▲15 oC

Viscosity ▲ 70 cp

Slag rate ▼ 100 kg/thm

ref

14

BF slag rate vs Alumina load slag alumina = 10 % , 15 % , 20 %,

Siderar

Inland 7

Thyssen Gy Posco Nagoya

Ijmuiden

Tata

Vizag

Bokaro Bhilai

Rautaruuki

170

220

270

320

370

420

15 25 35 45 55 65 75 85

Alumina load, kg / thm

Sla

g r

ate

, kg

/ t

hm

15

25 %

Can such

slags be

made to

flow ?

-40+10 mm

2% Al2O3

Industrial Practice of Iron Ore Processing – current and proposed

Lumps

Fines Slimes

Blast furnace charge

Sinter

plant

Iron Ore (ROM)

Crushing, screening,

classification plant

Tailing

pond -10+0.15 mm

2.7 % Al2O3

-0.15 mm

~8 % Al2O3

High alumina fines and slimes

Gravity separation

Magnetic separation

Froth flotation

Selective dispersion / flocculation

Bio - beneficiation

Discover optimum beneficiation

flowsheet

Enriched low

alumina product Residual Waste

Blast furnace

charge material

Agglomeration Semi-dry disposal

Iron rich cements Waste management

strategy Value-added products eco-

friendly storage

discard Plant 1 Plant 2 Plant 3 Plant 4 Plant 5 Plant 6 Plant 7 Plant 8 Plant 9

Slime Fe (%) 52.5 56-59 58 54.3 50 55 57 45 58.42

Al2O3(%) 7.4 7-10 3-5 7-8 8 7 6-7 9 3.72

SiO2 (%) 7.8 3.7-5.5 2.5-3.5 8-9 9 6 7-8 12 4.67

Slime discard % of ROM feed

24.8 13.5 18 18 12 15 17 25 16

Nature of iron ore and processing methods high Fe discard a study across several iron ore processing plants, India

Slime Dam Slime discard

12-25% of ROM

ROM: Hematite, Fe 59-64% , Alumina 3-5%, Silica 2.5-5%

Fineness…..difficulty in conventional beneficiation

Selective Flocculation - application in slime beneficiation

… water chemistry is adjusted to flocculate or disperse a particular particle type. This

process is typically used to remove very fine gangue particles

Selective flocculation and dispersion: using surface charge of particles

• The surface charge of any particle is a function of pH

• A high pH causes surfaces to become negative

• A low pH causes surfaces to become positive

Pilot Test Results of selective flocculation at Noamundi Mines

Impeller

Stand

Bucket for thickener underflow

Bucket for Flocculant Thickener

Fig No: 6 prepared test work setup

Tank

Schematic Test work setup

Fe% Alumina% Silica%

Feed 56 6.25 6.06

Product 64 3.22 2.75

Reject 42 13.10 13.68

Results

Product Fe% ~7%

Reject Fe% ~14%

Yield ~ 63%

Results “selective flocculation” induced recovery of values from ‘slime’

Results of “selective flocculation” ~ 90% Fe recovery with only 40 % alumina reporting to concentrate

“know thy ore” – navigating ore quality effects

..Iron Ore Agglomeration

Sinter alumina: experience at Tata Steel

Lowers sinter strength Raises sinter RDI Lowers sinter size

Alumina in ore, flux, fuel Countered by

Higher heat input sintering Higher flux addition

High FeO - Less reducible sinter

Higher CaO - more slag content

Blast Furnaces

Lower productivity Higher Fuel rate

24

Alumina effects in sintering …

energy consumption ↑ sinter strength ↓

71.6

71.8

72.0

72.2

72.4

72.6

72.8

73.0

73.2

73.4

73.6

2.00 2.10 2.20 2.30 2.40 2.50 2.60

Tu

mle

r In

de

x (

+6

.3m

m,%

)

Al2O3, %

Al2O3,% vs sinter strength weekly averages

25

Ore fineness and moisture effects…

high Blaine .. Joda ore pellets .. deformed high moisture, high Blaine

normal run… Noa ore run

27

Ore characteristics beyond the chemistry of ore …mineralogy

Association of iron phase Mineral Chemical Formula

Fe2O3

FeO(OH) /

Fe2O3.H2O

Untreated Goethite Heat treated @400 C Goethite

ΔH

H20

1. Productivity

2. Heat Input

Fe2O3.H2O Fe2O3

Few of the minerals in iron ore

Hematite α-Fe2O3

Hydro hematite Fe2O3.nH2O

Maghemite γ-Fe2O3

Magnetite Fe3O4

Goethite α-FeOOH Lepidocrocite γ-FeOOH Ferrihydrite (6-line) Fe1.55O1.66(OH)1.34

Gibbsite Al(OH)3

Kaolinite Al2Si2O5(OH)4

Transformation of minerals during heating

Hematite (Fe2O3)

Magnetite (Fe3O4)

Hydro-hematite Lepidocrocite

small endothermic peak appears at about 675–680 °C

480–1000 °C exothermic, oxidation

Hematite (Fe2O3)

Gibbsite Al(OH)3

Goethite FeO(OH)

Kaolinite Al2Si2O5(OH)4

575oC

Endothermic peak due to de-hydroxilation

1000oC Exothermic peak

Mullite (2 Al2O3. SiO2)

240oC 560oC

Endothermic Boehmtite AlO(OH)

800oC

Exothermic ɣAl2O3

395oC

Endothermic Alpha Hematite (α Fe2O3)

350oC

Endothermic Gamma Hematite (ɣ Fe2O3)

400oC

Exothermic Alpha Hematite (αFe2O3)

275–450 °C Exothermic Oxidation

Thermal processing tests as a means of deciphering mineral

constituents and their behavior

Thermal Analysis (TA) - a group of techniques that study the properties of materials

as they change with temperature ... Includes several different methods. These are distinguished from one another by the property which is measured.

Thermogravimetric analysis TGA Differential scanning calorimetry DSC

weight loss curve • changes in sample composition

• thermal stability

• kinetic parameters for chemical reactions in the sample

– Measure heat absorbed or liberated during heating or cooling

DSC curve phase transitions, dehydration, gas

evolution, melting, crystallization

oxidation stability, direct measurement of heat capacity

– Measure mass change during heating or cooling

31

Thermal behavior of different pure hydrous minerals, heat absorbed as function of temperature

Goethite Hydro-hematite Gibbsite Kaolinite

Single Endothermic peak

Start decomposition at 340

deg.C

Culminates to peak around 395

Deg. C

Goethite gives alpha-hematite

on decomposition

Temp (degree Centigrade) Temp (degree Centigrade) Temp (degree Centigrade) Temp (degree Centigrade)

The grain size, purity, and physical structure are also important in determining the temperature of decomposition

Endothermic followed by

exothermic peak

Start decomposition at 300oC

Culminates to peak around 350 oC

Hydro hematite gives gamma

hematite endothermic peak

Gamma hematite transform to

alpha Hematite Exothermic

350oC 395oC

350oC 300oC 350oC

240oC

560oC

300oC

575oC

1000oC

Three endothermic peaks

Peak 1 Gibbsite decomposes

to Bohemite 6.3% weight loss

Peak 2 Remaining Gibbsite

decomposes to Bohemite,

22.3% weight loss

Peak 3 Bohemite

decomposes gamma-alumina

2

1 1

1

2

3

1

2

One endothermic peak

followed by one exothermic

peak

Peak 1 Endothermic peak

due to de-hydroxilation

Peak 2 Exothermic peak

due to mullite formation

Thermogram of Lat-3

Mineral Makeup • Goethite • Hydro Hematite • Quartz

Observations 1. Two distinctive peak one for Goethite and one for Hydro hematite 2. While they both have the same chemical composition (Fe2O3.H2O), they differ structurally in the nature of

bonding of the hydrogen atom 3. In Goethite, the hydrogen atom act as a cation between oxygen atoms and in Hydro hematite hydrogen

atom is present in discrete OH group

VIRTUAL Ore Pile: synthesis of quality and stacking data

image transmission

Iron ore pile at Noamundi – for dispatch of ore to Pellet

Plant at Jamshedpur

“virtual iron ore pile”

Prediction of chemistry, mineralogy, size – for ~ one week’s supply

time series data of: • Stacker position • Discharge tph • Ore chemistry • Ore ptl size

Use of geological models Resource estimation

Bore hole results +

other information

Ore mineralogy .. effects on pelletizing performance

y = -0.1005x + 25.462 R² = 0.1611

23

23.5

24

24.5

25

25.5

5 10 15 20 25

Gro

ss p

rod

uct

ivit

y (t

/m2

/d)

Estimated % Goethite in ore

Pellet plant weekly data Jan'13-Jan'15, Availability >85%

y = 15.111x + 709.89 R² = 0.3207

750

800

850

900

950

1000

1050

1100

1150

0 5 10 15 20 25

Hea

t in

pu

t (M

J/t)

Estimated Goethite in Ore, %

Pellet plant weekly data Jan'13-Jan'15, Availability >85%

Productivity Energy consumption

37

Data Analytics for smoothening agglomeration thinking beyond the chemistry of ore …mineralogy

Association of iron phase Mineral Chemical Formula

Fe2O3

FeO(OH) /

Fe2O3.H2O

Untreated Goethite Heat treated @400 C Goethite

ΔH

H20

Productivity

Heat Input

Fe2O3.H2O Fe2O3

Adjusting pellet induration profile – based on diagnosed ore characteristics

0 200 400 600 800 1000 1200-3

-2.5

-2

-1.5

-1

-0.5

0

Temperature, oC

Weig

ht

loss,

wt%

Different ores demand heat at characteristic temperatures

A mismatch causes deficiency or excess heat poor pellets

Adjust burner settings and process to respond to measured ore characteristics

Appropriate thermal history ensures pellet quality

India summary Iron Ore Developments – view from a growing mining and steel industry

Iron ore reserves Large hematite resource base – needs rapid development, scale and facilitation

Nature of the iron ore “sticky” alumina problem in eastern India hematite goethitic ores Magnetite potential not yet explored adequately

Alumina Continues to be a difficult chapter in Indian BF ironmaking

Beneficiation challenges Complex flowsheets – leveraging gravity, magnetic, surface forces targeting specific size fractions

appear relevant

Agglomeration developments Process interventions guided by mineralogical characterization hold promise

40

Thank you

41