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TATA INNOVISTA 2013 - Regional Round Winner

Silent Sizing of Ferroalloy Cake

Silent Sizing of Ferroalloy Cake using a chemical additive

D67213121840 Dare To Try

Mr. Veerendra Singh Principal Researcher, R&D, Tata Steel Mr. Prabhash Gokarn Head, Raw Material Projects, Tata Steel Mr. Chandan Singh Sr Manager, KVHS, Tata Steel Mr. Ganesh Sahu Head, FAP Bamnipal, Tata Steel Mr. Subhakant Sarangi Manager, FAP Bamnipal, Tata Steel

Tata Innovista, Finals 25th April, 2013

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1. Background - Ferroalloy Production Process 2 slides

2. Trigger – eliminate/reduce manual sizing 1 slide

3. An Unlikely Source of Inspiration 1 slide

4. Construction Site Demolition Using Chemicals 1 slide

5. Concept Testing & Projected Benefits 1 slide

6. Plant Trials 3 slides

7. Failure and its Analysis 2 slide

8. Raring to Go - Why we will be Back 1 slide

D67213121840 Silent Sizing of Ferroalloy Cake

Presentation Structure

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D67213121840 Silent Sizing of Ferroalloy Cake

Background Business Ferroalloys* are used to produce almost all quality steels

~ 80 % of Ferroalloys used in steel making – deoxidation & alloying

Ferroalloys contribute 5 % - 30% of steelmaking cost

World Ferroalloy production - 30 mTPA in 2012.

India among top 5 Ferroalloy producers of the world

Tata Steel produces ~350kTPA Ferroalloys (FeCr, FeMn, SiMn) -

6th largest producer of FeCr, largest ferroalloy player in India

* Bulk – FeCr(incl ChCr), FeMn, SiMn, FeSi… Noble - FeTi, FeNb, FeV, FeMo, FeB … FeMn FeCr SiMn

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D67213121840 Silent Sizing of Ferroalloy Cake

Ferroalloy Production Process

Submerged Arc Furnace

Liquid Metal Cast in Pans

Metal Cakes Need to Be Sized

Sizing

Ferroalloy Production

Smelting-reduction (@ 1700o C)

Casting of liquid ferroalloy

Sizing (2m→300mm→80mm)

Packing and Despatch

Sized Lumps

Fines

Steel Making

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Crushing Machine

High generation of fines

D67213121840 Silent Sizing of Ferroalloy Cake

Trigger – eliminate/reduce manual sizing

Search for Alternates to Manual Sizing Pig Caster

Low Yield X Blasting

Unsafe X X

Manual Sizing :

- Large number of unskilled labour

- Direct & Indirect cost of high labour

- Safety Concerns

- Periodic IR Issues

- Rising aspirations of people – cost, availability

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D67213121840 Silent Sizing of Ferroalloy Cake

An Unlikely Source of Inspiration

Use of chemicals for Ferroalloy Sizing

Search for Comminution additives …

Bursting of water pipeline in cold ?

Silent demolition agents

(Construction Industry)

• CaO Based Powder • Cost Rs 20/Kg • Pressure : 100MPa

Water Ice

Rock

4% vol

Ettringite crystal

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D67213121840 Silent Sizing of Ferroalloy Cake

Construction Site Demolition Using Chemicals

Demolition of a Concrete Structure using a Chemical Reagent

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D67213121840 Silent Sizing of Ferroalloy Cake

Concept & Lab Testing

Procedure Step -1 : Making holes in cake step -2 : Filling additive slurry Step -3 : Allow expansion (2-12 hours) Step -4 : Optimize process variables (time and hole spacing)

Lab Testing

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D67213121840 Silent Sizing of Ferroalloy Cake

Potential Benefits

1. Economic • Current cost of sizing : Rs 300/ton • Cost after the process developed : Rs 150/ton • Total Saving for all the plants (FeCr, ChCr, SiMn, FeMn) (Rs):

= 350,000*150 = Rs 5,250,000 = Rs 5.2 Crore/year

2. Environmental • Lower dust generation • Reduced noise pollution • Energy used in mechanical crushing saved

3. Social • Improved process safety • Lowers unskilled manual labor • Productivity (specially hot summer, rains, festivals)

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D67213121840 Silent Sizing of Ferroalloy Cake

Plant Trials – Challenges Faced

Challenges

C-1: Making the holes C-2: Safe handling of cake

from casting bed to handing yard.

C-3: Avoiding possibilities

of flying broken pieces

Yes, now problems are solved

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D67213121840 Silent Sizing of Ferroalloy Cake

Research: Plant Trials

Trial -1

(a) Use refractory pipes during casting

(b) Cake removed and quenched

(c) Hole Cleaned and slurry filled

ProcedureProcedure

• One single crack generated passing trough the hole.

• Differential cooling and brittleness of material is main reason of this

ResultResult

Single crack …….

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D67213121840 Silent Sizing of Ferroalloy Cake

Research: Plant Trials

Trial -2

(a) Made ridge in bed

(b) Cake removed and quenched

(c) Openings cleaned and slurry filled

ProcedureProcedure

• Improper fragmentation • Brittleness of material is main

reason of this

ResultResult

Poor Fragmentation…….

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D67213121840 Silent Sizing of Ferroalloy Cake

Failure Analysis.....

Poor fragmentation

• Only one/few cracks formed

• Inadequate help to sizing

Not overcome despite many combinations of holes & slurry

composition.

Safety Limitation

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D67213121840 Silent Sizing of Ferroalloy Cake

Failure Analysis.....

Poor Fragmentation…….

Single crack …….

(a) Ferroalloy Sample (b) Rock Sample

Material properties are main reason of failure

a) Brittleness

b) No micro- cracks

c) Slow rate of loading

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D67213121840 Silent Sizing of Ferroalloy Cake

Management Encouragement Made Us ……

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D67213121840 Silent Sizing of Ferroalloy Cake

........Raring to Go – Why We Will Be Back

Explore • Use at Dolomite and Manganese mines (Explosive , Safety , Yield )

• Use in fragmenting high Silica FeCr chunks

Dolomite boulders broken using Split AG

Current Status : Successful Plant Trials at Gomardih Process Development Trials in Progress

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Silent Sizing of Ferroalloy Cake

Questions

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Thank You

KVHS

Mr. Pankaj Lochan Mr. A Bhattacharjee