International Conference Industrial Waste & Wastewater Treatment & Valorisation

APPLICATION OF STAINLESS STEEL SLAG WASTE AS A PARTIAL REPLACEMENT TO MANUFACTURE

CEMENT MORTARS

Julia Rosales, University of Córdoba, SpainConstruction Engineering- University of Cordoba (Spain)

International Stainless Steel Forum, 2014

15

20

25

30

35

40

2000 2002 2004 2006 2008 2010 2012 2014

Mill

ion

met

ric to

nne

(Mt)

Spain 3rd Europeanproducer

INTRODUCTIONSTAINLESS STEEL PRODUCTION

48%

20141st ASIA (71%)

2nd EUROPE (21%)

3rd AMERICA (8%)

Italy (25%)

Germany (19%)

Spain (15%)

France (8%)

Poland (6%)

Belgium (4%)

Finlande (4%)

Luxembourg (3%)

UK (3%)

Others (13%) World Steel Asociation, 2013

INTRODUCTIONSTAINLESS STEEL MANUFACTURING PROCESS

Raw materials Melting RefiningAOD

WASTE

RefiningVOD

Ladle RefiningLF

Continuous casting Surface

grinding

Grinded slab

AGGREGATES SLAG

20% Raw Materials

85% Waste LANDFILL

VALORISATION

INTRODUCTIONVALORIZATION STAINLESS STEEL WASTE

CONSTRUCTION

AGGREGATES

• Road base• Concrete• Addition to Clinker

SLAG

AGRICULTURE• Soil improvement

CONSTRUCTION

AGRICULTURE

• Soil-cement• Concrete• CEMENT MORTAR

• Soil improvementTREATING WASTEWATER

WASTE UTILIZATION

LESS USE OF NATURAL

RESOURCES

SUSTAINABILITY

OBJETIVESSTAINLESS STEEL SLAG WASTE (SW) AS CEMENT REPLACEMENT IN MORTAR

Few research related to stainless steel slag waste for use as a substitute for cement

Principal objetive: study of cement replacement by differentpercentages of stainless steel slags crushed and without crushed formaking mortars to determine the optimal replacement rate to increasethe economic value of stainless steel slag waste and decrease thecement content

TREATMENT AND PROCESSING OF SW

• Study the cementitious properties

• Analysis of environmental effects through leaching test

• Study the effect on the compressive strength, flexural and shrinkage

• Application of multivariate analysis methods

RESEARCH DESIGNSTAINLESS STEEL SLAG WASTE AS CEMENT REPLACEMENT IN MORTAR

SW

PROCESSING

SW

Unprocessed

SW-C

Crushed - Sieved

REPLACEMENT

10%CEM20%CEM30%CEM

MANUFACTURE OF MORTAR

COMPRESSIVE STRENGTH FLEXURAL STRENGTHSHRINKAGEMULTIVARIATE ANALYSIS

OXIDE COMPOSITIONLEACHING

Stainless SteelSteel

STAINLESS STEEL FACTORY ACERINOX

MATERIALS ANDEXPERIMENTAL METHODS

STAINLESS STEEL SLAG WASTE AS CEMENT REPLACEMENT IN MORTAR

X-ray fluorescence(XRF) (UNE-EN 196-2)

CHEMICAL ANALYSIS

Leaching test (UNE- EN 12457-3)

Compressive Strength1-7-28-90 DAYS (UNE-EN 196-1)

MECHANICAL ANALYSIS

Fexural Strength1-7-28-90 DAYS(UNE-EN 196-1)

Shrinkage1-7-14-28-56-90 DAYS

(UNE-83831)

CEM

SW

SW-C

CONTROL

SW-CREPLACEMENT10% 20% 30%

SWREPLACEMENT10% 20% 30%

Standardized Sand + Water

CHEMICAL PROPERTIESRESULTS

X-RAY FLUORESCENCE (XRF)CEMENTITIOUS PROPERTIES SW AND SW-C

SiO2 (%) Al2O3 (%) Fe2O3 (%) CaO (%) MgO (%) SO3 (%) K2O (%)

SW 31,34 5,18 1,25 46,26 10,90 0,37 0,00

SW-C 30,31 5,01 0,93 46,45 11,51 0,36 0,00

0

10

20

30

40

50

60

70

80

90

SiO2 (%) Al2O3 (%) Fe2O3 (%) CaO (%) MgO (%) SO3 (%) K2O (%)

Perc

enta

ge (%

)

SW SW-C LIMITS

Chemical composition limits pozzolanic materials(Calleja, J. 1985)

CHEMICAL COMPOSITION SIMILAR• CLINKER• CONVENTIONAL FLY ASH

POZZOLANIC REACTION CHARACTERISTICS

0,001

0,01

0,1

1

10

100

Ni Cu Cr Zn As Se Mo Cd Sb Ba Hg Pb

Stainless steel slagL/S = 2 l/kg

0,001

0,01

0,1

1

10

100

1000

Ni Cu Cr Zn As Se Mo Cd Sb Ba Hg Pb

Stainless steel slagL/S = 10 l/kg

NON HAZARDOUS

CHROMIUMMOLYBDENUM

LEACHING TESTHEAVY METALS LEACHATE BY SW AND SW-C

Con

cent

ratio

nsin

the

leac

hate

(mg/

kg)

HAZARDOUS NON-HAZARDOUS INERT

Sw Sw-C

ClassificationL/S=2

SW Non hazardous

SW-C Non hazardous

L/S=10

SW Non hazardous

SW-C Non hazardous

CHEMICAL PROPERTIESRESULTS

0102030405060

0 50 100

0

10

20

30

40

50

60

0 50 100Time (d)

0

10

20

30

40

50

60

0 50 100

S110% REPLACEMENT

S220% REPLACEMENT

S330% REPLACEMENT

REPLACEMENT 10% SwAND Sw-C COMPRESSIVE STRENGTH INCREASES

LOSS OF COMPRESSIVE STRENGTH LOWER 25%

SW-C BETTER RESULTS

COMPRESSIVE STRENGTHSTAINLESS STEEL SLAG WASTE AS CEMENT REPLACEMENT IN MORTAR

Com

pres

sive

stre

ngth

(Mpa

) 28 DAYSa a a

b b

dc

Com

pres

sive

stre

ngth

(Mpa

)

Sw Sw-CCR

MECHANICAL BEHAVIORRESULTS

REPLACEMENT 10% SwAND Sw-C FLEXURAL

STRENGTH INCREASES

LOSS OF FLEXURAL STRENGTH LOWER 15%

FLEXURAL STRENGTHSTAINLESS STEEL SLAG WASTE AS CEMENT REPLACEMENT IN MORTAR

y = 0,1391x + 3,9232R² = 0,9455

99,510

10,511

11,512

12,5

35 40 45 50 55 60

Flex

ural

stre

ngth

(Mpa

)

Compressive strength (Mpa)

HIGH POSITIVE CORRELATION AMONG

THE COMPRESSIVE STRENGTH AND

FLEXURAL STRENGTH

28 DAYS

Flex

ural

stre

ngth

(Mpa

) ba a

b bc c

FLEXURAL STRENGTH VSCOMPRESIVE STRENGTH

MECHANICAL BEHAVIORRESULTS

REPLACEMENT 10% SwAND Sw-C PRESENT

VALUES OF RETRACTION SIMILAR THAT THE

CONTROL

SHRINKAGESTAINLESS STEEL SLAG WASTE AS CEMENT REPLACEMENT IN MORTAR

0,000

0,200

0,400

0,600

0,800

1,000

1,200

1,400

0 20 40 60 80 100

shrin

kage

(μm

/m)

Age (days)

Control S1-Sw S1-Sw-C S2-SwS2-Sw-C S3-Sw S3-Sw-C

THE MORTARS WITH A REPLACEMENT OF 20% AND 30% Sw AND Sw-C HAVE HIGH SHRINKAGE

VALUES

MECHANICAL BEHAVIORRESULTS

MULTIVARIATE ANALYSIS

SAS 9.4

The mechanical behavior of mortars must be analyzed as a whole(Compressive Strength, Flexural Strength and Shrinkage)

Multivariate analysis: a useful tool to evaluate the influence of addition of slag waste in the mechanical behavior

MATERIALS ANDEXPERIMENTAL METHODS

MULTIVARIATE ANALYSIS METHODS

• Ordination Analysis. Principal Components Analysis (PCA)

• Multivariate Analysis of Variance (MANOVAs)

RESULTSMULTIVARIATE ANALYSIS

MANOVAs

Pillai approx F Pr(>F)

Control vs S1 0,6775 23,11 < 0,0001 ***

Control vs S2 0,6279 18,56 < 0,0001 ***

Control vs S3 0,9691 345,75 < 0,0001 ***

Pillai approx F Pr(>F)

Mechanicalbehavior vs All

treatment1,86 9,53 < 0,0001

*** DIFFERENT

DIFFER

ENTS

Pillai approx F Pr(>F)

SW vs SW-C 0,7037 26,12 < 0,0001 ***

S2SW vs S2SW-C 0,1827 2,46 0,08

Control vs Replacement Series

Unprocessed vs Crushed

CONCLUSIONSSTAINLESS STEEL SLAG WASTE AS CEMENT REPLACEMENT IN MORTAR

The replacement cement by stainless steel slag waste for the manufactureof mortar improves the mechanical behavior, valorizing this waste andreducing the consumption of raw materials, obtaining as a result aproduct that not cause environmentally effects according to the leachatesanalysis.

The stainless steel slags have presented high values metal oxides similarto those present in conventional fly ash. These values result in positivitycementitious capacity in the stainless steel slag waste.

The use of multivariate analysis can be a useful tools to evaluate the effectof this waste as a replacement of cement.

The cement replacement by stainless steel slag wasteprovides an increased in compressive and flexural strengthfor 10% substitution respect to the control. For stainlesssteel slag waste crushed we are observed better results. Formortars manufactured with this percentage, the retractionsare similar to the control mortar.

THANKS FOR YOUR ATTENTIONTHANKS FOR YOUR ATTENTION

International Conference Industrial Waste & Wastewater Treatment & Valorisation

APPLICATION OF STAINLESS STEEL SLAG WASTE AS A PARTIAL REPLACEMENT TO MANUFACTURE

CEMENT MORTARSJulia Rosales, University of Córdoba, Spain

juliarosalesgarcia@gmail.com

J. Rosales – F. Agrela – M. Cabrera – M.G. Beltrán – J.Ayuso