Transcript Paper title
Global Slag Utilisation
Nick Jones Slag Business Development Manager
Presentation Outline
Why utilise slag?
MultiServ overview Types of slag handled / markets supplied A focus on steel slag Steel slag properties / benefits Case Studies Conclusions
Why Utilise Slag?
Historically • Either sent to landfill or de-metalled and sent to landfill – A WASTE Current world- wide situation • Landfill becoming scarce or more expensive or both • Natural aggregate resources are becoming more difficult to develop • The environmental impact of Quarrying • The world is becoming more environmentally aware – planning for the future
Why Utilise Slag?
When processed and marketed correctly, slag is not a waste, it is a resource Why remove aggregate from the ground when slag can be used as a substitute (reduce waste – conserve resources) Protect and preserve our environment Benefit from technical advantages offered by many of the steel making slags High performance products not necessarily low grade applications
MultiServ Structure
Europe North
Czech Rep.
Finland Netherlands Norway Serbia Slovakia Sweden UK
30 Europe South
Belgium France Italy Luxembourg Portugal Spain
International
Australia Bahrain China Egypt Indonesia New Zealand Saudi Arabia South Africa Thailand
Latin America
Argentina Brazil Chile Guatemala Mexico Peru Trinidad Venezuela
36 22 +160 Operating Sites 34 North America
Canada USA
40
Types of Ferrous Slag Handled
Iron making slag • Air-cooled blast furnace slag • Granulated blast furnace slag • Melter slag Steel making slag • BOF • EAF • Stainless EAF AOD
Typical MultiServ Global Slag Sales
North America Latin America Rest of World* Total * Europe, Asia, Middle East & Africa Iron and Steel Slag Sales (Tonnes) 3,490,000 1,245,000 2,256,000 6,991,000
Global Slag Sales Breakdown
Road Construction General Construction Agriculture Environmental Diverse Applications % Sales 62% 16% 0.1
1.9% 20% Revenues based on “Global” averages per application
Typical Slag Applications
Stone Columns Rail Ballast Sea Defences Filter Media Cement Dyke Repairs Agricultural Gabion Baskets Road Surface Aggregates Asphalt Sub Bases (unbound) Road Bases (unbound) Bulk Fill Low Volume = Niche Applications High Volume = Bulk Applications
Typical Applications
Road construction • Unbound • Slag bound • Asphalt General construction • Fill Unconfined – steel slag • Concrete Non-structural – steel slag
Typical Applications
Agriculture • Fertiliser • Soil conditioners Environmental • Filtration • Waste water treatment Recycling to steel mill Ground stabilisation – Vibro-floatation Mineral wool – insulation Cement manufacture Railway ballast
Unbound applications
Germany – Sub-bases Holland – sub-bases, slag bound mixtures • Pass environmental standards • Leachate tests – ground Ensure that the slag is not placed in stagnant water conditions UK – guidance for blast furnace slag – similar controls should apply
Waste water treatment (NZ)
Ground Stabilisation
MultiServ Saudi Arabia has supplied EAF steel slag from the Hadeed steel mill into stone column piling since Nov 1995 Since that time 21 construction project have been supplied, consuming over 970,000 Tonnes of steel slag aggregate The size fractions used are 19/37 for dry applications and 25/75 for wet
Ground Stabilisation
Typical Ground Stabilisation Project
Feedstock for Cement Manufacture Steel Slag Steel Slag
A Focus on Steel Slag
Steel Slag Properties
Steel slag is an ideal aggregate for asphalt surfacing materials especially with regards to the following properties Cubical Shape – Resistance to deformation pH – Resistance to binder stripping – Durability – Porous asphalt Resistance to polishing – Skid resistance - Safety Resistance to abrasion – Durability
Shape Resistance to Deformation
Wheeltracker
Wheeltracking Rate at 60
o
C
10 4 2 8 6 0
Singapore Granite Ste e l Slag
Nottingham Asphalt Tester
Determines fundamental properties Values are understood worldwide Stiffness Resistance to deformation Fatigue
pH-Affinity to Bitumen Durability
SCRIM
SFC Values for 14mm steel slag surface dressing laid in 1988
15000 13000 11000 9000 1990 1992 1994 1996 1998
Date Tested
2000 AADT SFC 2002 2004 0.65
0.6
0.55
0.5
0.45
0.4
0.35
0.3
2006
Direct Comparison Between Steel Slag and High PSV Gritstone
0.54
0.52
0.5
0.48
0.46
0.44
0.42
0.4
1994 1997 1999 Date Tested SteelSlag Gritstone
Grip Tester
WARNING!
FREE LIME
Result of Expansive Slag in Asphalt
Expansion Test
Expansion Tests Equipment
Expansion Test
Case Studies
UK - Steelphalt – EAF and stainless steel slag into asphalt Saudi Arabia – steel slag into asphalt South Africa - BOS steel slag asphalt
UK
MultiServ own their own Steel slag asphalt coating facility (SteelPhalt) in the UK Started coating steel slag in 1934 Since coated over 12 Million Tonnes 100% utilisation of primary slag produced from four steel mills in the area No primary slag tips in local area
UK
Two asphalt plants – 640T Storage capacity Asphalt Production 360,000 tpa 220K Tonnes steel slag 130K Tonnes carbon steel slag 90K Tonnes stainless steel slag 140K Tonnes limestone
UK
UK Steelphalt production 220KT/yr • carbon steel slag / stainless steel slag CS EAF – surface course asphalt – all sizes SS EAF – 3mm – metallic recovery SS AOD – stabilised – base course asphalt Supplies to local and National specification Supplies proprietary thin surfacing systems in accordance with an independent product approval scheme • SteelPave - suite of thin surfacing systems • SteelSurf – for high stress applications
Steelphalt Thin Surfacings
SteelSurf
Saudi Arabia
Saudi Arabia • Markets all its 450KT/yr of electric arc furnace steels slag • Two largest markets – Road construction Ground stabilisation • Boasts our largest road construction contract consuming over 700,000 tonnes of steel slag in: Unbound road base Asphalt base course Asphalt surface course
Saudi Arabia – Road Construction +700KT of Steel Slag
South Africa
South Africa 150 – 200KT/yr • Newly developed market • Aggregate for asphalt supply to busiest motorway in RSA Large segregated stock of BOF steel slag Highways authority had problems with local aggregate in asphalt • Premature deformation • Fines stripping in asphalt
South Africa
Lab tests and site trials undertaken in partnership with local asphalt manufacturer to prove material properties and demonstrate advantages Consulting engineer specifies slag to combat problems Market has been established and is growing Slag is now specified for its benefits Experience and confidence gained from using slag from this one site will pave the way for extended use of slag from other sources across RSA
Deformation
N3 Patching - Trial
Van Reenen’s Pass
Conclusions
Steel slag is a resource, not a waste Steel slag can be utilised as a high quality aggregate. If processed correctly steel slag can be used as aggregate for a variety of applications giving benefits over and above many natural aggregates
Conclusions
As the world reviews its environmental policies opportunities arise for increased use of industrial by-products The use of steel slags can be a win-win result for the environment • Reduction of waste • Conservation of natural resources