Presentation on

THRESHOLD VALUE OF IRON ORE

P.Ramesh Babu (DGM-Geology)

S.Manoj Kumar (SM – Ore Dressing)

CONTENTS

oIron ore formation and deposits

o Distribution and occurrence

oSAIL Iron ore mines overview

oCaptive Mines of Bhilai Steel Plant

o Profile of Dalli-Rajhara Mines

oData Modeling of Dalli-Rajhara Mines

oThreshold value-issues & limitations

o Mineralogy of Dalli-Rajhara

oBeneficiability

oConclusion

o References

Magnetite Hematite Goethite Limonite

SAIL – Iron Ore Mines Overview

SL.

NO MINE State YOC

Rated

capacity

Original

Reserves

Remaining

(As on

Apr`2017) Quality

Iron Ore Fe% SiO2 Al2O3

1. Kiriburu Jharkhand 1964 5.5 33 27.25 62.97 3.51 2.57

2. Meghahataburu Jharkhand 1985 6.5 22.5 11.41 61.52 4.58 2.73

3. Bolani Orissa 1960 10 143.5 57.68 62.95 2.83 3.03

4. Barsua/Taldih Orissa 1960 3 74.25 30.11 61.77 2.88 3.76

5. Kalta Orissa 1966 2.5 66.8 20.68 62.50 2.97 3.26

6. Gua Jharkhand 1919 10 140.75 67.38 61.93 3.40 2.90

7. Manoharpur

(Chiria) Jharkhand 1907 5 1200 966 62.14 2.68 2.74

8. Dalli-Rajhara Chattisgarh 1958 9 301.95 93.76 62.32 7.02 1.86

9 Rowghat

Chattisgarh

2021* 14 511 511 63 3

1.5

To ensure continuous supply of Quality Raw Materials to Bhilai Steel

Plant in tune with the growth plan of Hot Metal on a sustainable

basis.

THE VISION

MINES ORGANISATION - BHILAI STEEL PLANT

BSP MINES LOCATIONS

25 km

100 km

135 km 275 km

198 km

MINING LEASES OF IRON ORE DEPOSITS BHILAI STEEL PLANT

NAME OF

MINES / LEASE MINERAL

PRESENT MINING LEASE STATUS

LEASE AREA (Ha.) VALIDITY

RAJHARA MECH Iron Ore 220.42 27-Apr-2023

DALLI MECH, J/DALLI &

KOKAN EAST Iron Ore 719.60 31-May-2023

DALLI MANUAL Iron Ore 100.00 20-Aug-2023

MAHAMAYA & DULKI Iron Ore 1522.67 03-Nov-2021

KALWAR (NEW) Iron Ore 938.06 Deemed renewed up

to 31/3/2025

ROWGHAT Iron Ore 2028.797 22-Sep-2029

IRON ORE RESERVES & THEIR

DEPLETION

NAME OF MINE

INITIAL

RESERVE

(MT)

BALANCE

RESERVE as

on 01.04.2017

(MT)

Fe% SiO2 %

RAJHARA 75.79 40.42 64.44 5.11

DALLI 118.85 22.11 61.60 8.40

JHARANDALLI 42.50 11.76 58.35 10.9

DALLI MNL 33.00 0.6 59.38 10.4

M/MAYA 23.19 10.25 59.48 9.50

DULKI (D-1) 8.62 8.62 63.26 3.95

TOTAL 301.95 93.76 62.32 7.02

7261 7219 7304

6904 6982 7156 7216 7302

7172

6742

4000

5000

6000

7000

8000

9000

2013-14 2014-15 2015-16 2016-17 2017-18(PR)

PRODUCTION DISPATCH

PRODUCTION & DISPATCH OF IRON ORE

‘ 000 T

* Production & Dispatch for 2017-18 has been taken on pro rata basis on present performance level and is likely to improve

7.303 7.909 7.926

7.169 7.685

2.149 2.655

7.66

6.072

4.349

9.452

10.564

15.586

13.241

12.034

0123456789

10111213141516

2013-14 2014-15 2015-16 2016-17 2017-18(PR)

ORE WASTE TOTAL

EXCAVATION OF ORE & WASTE MT

7.303 7.909 7.926

7.169 7.685

2.149 2.655

7.66

6.072

4.349

0123456789

10111213141516

2013-14 2014-15 2015-16 2016-17 2017-18(PR)

ORE WASTE stripping ratio sub-grade stock

Ratio ore : waste

The Rajhara Iron Mine of Balod district in the Indian state of Chhattisgarh

Mining Profile (X-Sec -DMM 480 RL)

Mining Profile (X-Sec -RMM 415 RL)

Modeling – Data Analysis

CATEGORY TONNES RFE RSIO2 RAL2O3 [Waste]

>55 19483498 62.86 6.77 1.76 >45 22627495 61.20 8.83 1.97 20700900 >35 23129770 60.79 9.38 1.99 20198626 >55 37383256 65.34 4.03 1.15 >45 40771569 64.09 5.33 1.32 2701875 >35 42609725 63.09 6.54 1.39 863719 >55 8845975 61.02 7.46 2.26 >45 11891805 58.44 10.71 2.67 5917518 >35 12195498 58.02 11.26 2.71 5613826

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

2010-11 2011-12 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18

Fe %(R) SiO2%(R) Al2O3%(R) Fe %(L)

SiO2%(L) Al2O3%(L) Fe %(F) SiO2%(F)

Al2O3%(F) Fe %(S) SiO2%(S) Al2O3%(S)

Quality Profile

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

2010-11 2011-12 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18

Fe %(R) SiO2%(R) Fe %(L) SiO2%(L)

Fe %(F) SiO2%(F) Fe %(S) SiO2%(S)

Quality Profile(Fe & SiO2))

PURPORT

"Rule 12(7)-Indian Bureau of Mines shall review the threshold values of minerals periodically in consultation with the stake holders." In view of the above comments and suggestions are hereby invited from all the stake holders including general public on the following aspects: 1.Inclusion or deletion of any major mineral from the list of minerals for which threshold value was notified in 2009, 2.Changes in the threshold value of the major minerals values of which were notified in 2009, with justifications,. 3.Suggested threshold value for the new major minerals proposed to be included in the list with justification.

• MINISTRY OF MINES INDIAN BUREAU OF MINES NOTIFICATION NAGPUR ,THE 16TH OCTOBER, 2009 No.T-45031/CGBM/2007(PF)

• THRESHOLD VALUE OF MINERALS FOR IMPLEMENTATION

• IRON ORE

(i)HEMATITIC IRON ORE: 45% Fe(MIN)

(ii) HEMATITIC SILICEOUS ORE (FOR ORE OF GOAN ORIGIN): 35% Fe(MIN)

"Threshold Value of minerals" means limit prescribed by the Indian Bureau of Mines from time to time based on the Beneficiability and or marketability of a mineral for a given region and a given time, below which a mineral obtained after mining can he discarded as waste."

ISSUE

The mine owners are directed to comply with following. 1. All the non-saleable/un-usable minerals/ ores above the limit prescribed in the threshold values are required to be stacked separately in the area earmarked for the purpose. 2. The mineral/ ore stock above the limit prescribed in the threshold values of minerals should be properly maintained in a bound register indicating the quantity and quality of material stacked. The month wise inventory of such materials shall be updated. 3. The overburden and waste material obtained during mining operation shall not be allowed to be mixed with the materials above the threshold values of minerals stacked.

Limitations

We have certain limitations like

• SAIL mines in this region were started operations before 1980’s with

large broken area out of total lease area.

• Due to non availability of space ; it is very difficult to extend the area

both laterally as well as vertically.

• MoEF insists to backfill the existing broken area and surrender for

fresh area clearances.

• Hence, area for dumping of waste and sub-grade ore is major

constraint in all mines.

Beneficiation Inevitability

MINERALOGICAL STUDIES – ROM Fines

MINERALOGICAL STUDIES – ROM Fines • fine size with size fractions of -1 to +12 mm with varying hues from yellow,

light to deep brown, there by physically suggesting moderate iron ore mineral content.

• The sample is moderately enriched in ore mineral content out of which 78% of them are ore minerals and the rest 22% is gangue content. The ore minerals include Hematite (H) and Goethite (G) and the gangue minerals are Ferruginous clay (Fcl) and Siliceous matrix ie Quartz(Q).

• Hematite is ubiquitous ore mineral by its contribution up to 72% followed by scanty mounts of Goethite (G) whose contribution is approximately 6% by area of their occurrence.

• Large and coarse-grained Hematite minerals do accommodate patches and medium to fine size inclusions of Ferruginous clay as well as Quartz, where as few of the coarse-grained and all most all the medium and fine size Hematite minerals do contain thin superficial coatings of Ferruginous clay matrix.

• None of the ore mineral grains are seen to occur in ‘free-state’ and all moat all the ore mineral grains either accommodate patches and/or inclusions of gangue mineral content or superficial coatings or thin layers of Ferruginous clay matrix.

MINERALOGICAL STUDIES - slimes

MINERALOGICAL STUDIES - slimes • The ore body showing characteristics of low to moderate grade ore

which comprises Hematite and Goethite as ore minerals and Quartz, Pseudo Ore and Ferruginous Clay as gangue minerals.

• Ore minerals distribution is around 40% as a whole and gangue minerals distribution is around 60% area as whole.

• Main ore mineral is Hematite with 25% area out of which around 9% grains are in free-state and remaining 16% grains are in un-liberated state. Around 7% un-liberated grains could be liberated at 25 micron size. Remaining un-liberated grains are in less than 15 micron size.

• Goethite covers around 15% area as a whole. All Goethite grains are in less than 70 micron size. Out of 15% Goethite, around 6% grains are in free-state and remaining 9% grains are in un-liberated state. All un-liberated grains are in less than 20 micron size.

MINERALOGICAL STUDIES-Summary

Hematite (H)

Goethite (G)

Ferruginous clay (Fcl)

Quartz(Q) Liberation size

Are

a D

istr

ibu

tio

n

ROM Fines

78% 22%

NA 72%

6%

Slimes

40% 60%

25% 15%

Liberated

9% 6% 15 µ

Generated Fines

(-1mm)

(+1-8mm)

(+8mm)

(Non-Mags)

To Slime Unit

(Mags)

GF Beneficiation – Process Flow

(+0.15-1mm) (- 0.15 mm)

CB 14

(Float)

(sink)

Pellet concentrates (Mags)

Slime Beneficiation - Process

Slime from Dam

Running Slime

Hopper Mixing Tank

From GF circuit

0.15 mm

…

…

…

…

…

…

…

…

…

…

…

…

…

…

…

…

…

…

…

Tailing

1.19 Mtpa

Fe: 37.1

%

SiO2 : 22.5 %

Al2O3 : 9.5 %

Concentrate

1.11 Mtpa

Fe: 65.4 %

SiO2 : 3.0 %

Al2O3 : 1.4 %

GF Slime

0.57 Mtpa

Fe: 55.6 %

SiO2: 10.0 %

Al2O3: 6.0 %

Capacity 2.33 Mtpa

Hydro cyclones for

de-sliming

WHIMS

Dewatering Hydro

cyclones

Ball Mill

Concentrate

Thickener

Pressure Filtration

Plant for

Concentrate

Tails Thickener

Running slime

0.35 Mtpa

Fe: 41.0 %

SiO2 : 20.6 %

Al2O3 : 12.3%

Hitkasa slime

1.38 Mtpa

Fe: 55.5

%;

SiO2 : 12.5 %;

Al2O3 : 3.7 %.

OPINION

• Industrial scale beneficiation works with 70-80% efficiency and practical assay gain of Fe content is only 4-4.5 unit.

• The problems associated with beneficiation of Iron ore are many fold.

• Generation of Substantial proportion of ROM as fines.

• Generation of Tailing and slimes.

• Economic utilisation/disposal of tailings and the related

environmental pollution

As per the rule16 of MCDR’2017,the sub-grade ore is to be mined out, but non-utilisability of low-grade iron ore is causing hindrance for the reclamation/rehabilitation of Pits as the total cost of production of the ore is also rise high.

Considering the present conditions, the threshold value of hematitic ore in Chattisgarh region may kindly be maintained at 45% Fe level content

or alternatively

intensive R&D studies activities may be patronised to find out economically viable beneficiation process by which low grade iron ore can be upgraded as per

industrial specification with high yield .