Sahaviriya Steel Industries UK

Iron & Steel Industry COIron & Steel Industry CO 22

CaptureCapture

Recent History of the Teesside PlantRecent History of the Teesside Plant

Iron & Steel making facility (Tata Steel) ceased production in  February 2010, ending 160 years of steel making in the area

Wharf operations  & coke making continued, but the rest of  the facility  was mothballed

SSI became owners of the facility on 25 March 2011

SSI UK currently directly employs c1800 employees

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SSI UK LocationSSI UK Location

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SSI UK SSI UK ––

Plant LayoutPlant Layout

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STEEL HOUSE

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CLEVELANDWORKS

LACKENBY WORKS

REDCAR WORKS

B.O.C.

River Tees

Ore Terminal

Coke Ovens

Blast Furnace

Sinter Plant

Steelmaking/Casting

South Bank Coke Ovens

Ownership retained by Tata

The ProcessThe Process

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Iron making Steelmaking

How is iron and steel made?

Coke Ovens

Sinter Plant

Redcar Blast Furnace

BOSPlant

Slab Casters

Redundant Bloom Caster

The Process The Process 

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RAW MATERIALSDeep water berth dredged to 17.0mtrsVessels range from coasters to large capes

REDCAR COKE OVENSTwo batteries of 66 ovens/battery.  5.36m high. 27.3t coal/ovenCoking rate of 25.4 mm/h with a charge to push cycle time of 18h

SOUTH BANK COKE OVENSTwo batteries of 44 ovens/battery.  5.36m high. 25.5t coal/ovenCoking rate of 20.5 mm/h with a charge to push cycle time of 

22h.

SINTER PLANT4.2m wide with 336m²

suction area

Annual production 4.0 Mt

The ProcessThe Process‐‐

IronmakingIronmaking

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Iron is produced at the  Teesside site from a 

single                        >10,000 tonnes/ day 

Blast furnace 

This unit has been  upgraded with the  addition of the 

Pulverised  Coal Injection

The Liquid iron product  from this process is 

transferred to the  Basic  Oxygen steelmaking 

Plant by Torpedo ladles 

Process Route Process Route  Primary Steelmaking Primary Steelmaking ‐‐

Capacity 4.88mtpa (2 Vessels)Capacity 4.88mtpa (2 Vessels)

3 x 250 tonne convertersTypical charge

225 tonnes liquid iron and 45 tonnes scrapAverage tapped weight 240 tonnesVessels equipped with

Bath agitation

Smart lances

Sub‐lance (data collection)

Slag splashing and washing

Primary Steelmaking

Process Route Process Route ‐‐

Slab CastingSlab Casting Capacity Capacity ‐‐

3.6Mtpa (Grade/Mix dependant)3.6Mtpa (Grade/Mix dependant)

Two twin strand castersTwin tundishes9.8 m radiusSizes

225 & 250 mm thick

1000‐2030 mm wide

Slab Casting

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Tundish

change practice

Tundish

Tube Changer

Full slab tracking

Computer logging 

SSI UK SSI UK ––

Restart of OperationsRestart of Operations

Major work programme and capital investment to bring the  plant back into operation 

Blast furnace restarted 15th

April 2012

First slab produced 18th

April 2012

First shipment left for SSI‐

Thailand 15th

May 2012

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Coke OvensCoke Ovens

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Process•The coal is loaded into the oven from the top.

•The oven is then heated from below driving off the volatile gasses.

•At the end of the heating phase the doors are opened and the Coke is then “pushed” out into the coke car.

•The coke car is then taken to the quench tower where the coke is quenched.

•The gas produced in the process is used around the site as a fuel source

Typical gas make up : -

CARBON MONOXIDE 6%

CARBON DIOXIDE 2%

HYDROGEN 62%

NITROGEN 2%

METHANE 26%

Blast Furnace ProcessBlast Furnace Process

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Process•Coke and iron ore are charged in layers at the top of the furnace.•Hot blast (Compressed air at @ 1400 ºC) is blown in at the bottom of the furnace causing a melting zone.•In this zone the coke breaks down creating CO which causes the final reduction of the iron ore.•As the blast passes up through the burden (solid material in the blast furnace) it reduces the burden travelling down the furnace.•At the top of the burden the compressed gasses, Blast Furnace Gas (BFG) is taken away for cleaning gad use in the process.

•The typical make up of the gas is : -CARBON MONOXIDE 23% CARBON DIOXIDE 21%HYDROGEN 2%NITROGEN 54%

PCI enhancement to Blast FurnacePCI enhancement to Blast Furnace

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PCI reduces the amount of coal used in the production of each unit of hot iron and enables higher oxygen enrichment thus reducing Nitrogen in the Gas produced.

BOS ProcessBOS Process

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Process•The vessel is charged with scrap @ 50 tonne.•The hot metal is then charged over the top and the vessel is raised to the vertical.•The oxygen lance is lowered and the “blow” started.•Pure oxygen is blown at the molten iron at supersonic speeds, causing the carbon to be freed to CO.•After the Carbon is removed from the Iron producing Steel the blow is stopped and the vessel is tilted and the steel “Tapped” off.•Typical make up of the gas coming of the BOS vessels is: -

Carbon monoxide 50 – 70%Carbon dioxide 10 – 20%Oxygen 0.5 – 2%Nitrogen and others 15 – 20%

BFG volumesBFG volumes

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Fig 1

Fig 2

Fig 1 Shows the fluctuations in BFG volume over 2 hours from 0900 4th March 2014. The range is 400kNm^3/h to 600kNm^3/h.

Fig 2 Shows the fluctuations in BFG volume over one month (Feb 14). The range is 400kNm^3/h to 630kNm^3/h. The figures lower than 400kNm^3/h are the blast shutting down and restarting.

BFG compositionsBFG compositions

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Fig 3

Fig 4

Fig 3 Shows the gas composition fluctuations of Hydrogen, CO2 and CO in the BFG over 2 hours.

Fig 4 Shows the gas composition fluctuations of Hydrogen, CO2 and CO in the BFG over one month.

BOS Gas BOS Gas 

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Fig 5

Fig 5 Shows the change in make up of gas over the blow cycle which is approximately 16 minutes long.The blows are on average done twice an hour.Due to the oxygen content at the start and end of the blow the gas is flared for safety in a BOS gas collection process.