the application of fluidized fly ash a new kind of waste material...

INSTITUTE OF FUNDMENTAL TECHNOLOGICAL RESEARCH

POLISH ACADEMY OF SCIENCES

WARSAW POLANDWARSAW, POLAND

The application of fluidized fly ash a new kind of waste materiala new kind of waste material

in concrete technology

Daria Jóźwiak-Niedźwiedzka

Anna Maria Island, X Workshop

1

CONTENTSCONTENTS

Fluidized fly ash what is it? Fluidized fly ash, what is it?

Aims of research

Examples of test results

Conclusions Conclusions

Anna Maria Island, X Workshop November 4-6, 2009

Fluidized fly ash, what is it? 2

Reduction of harmful emission to the atmosphereDirective 2001/80/WE

(reduction of sulphur and NOx)( p x)

New coal combustion technique in power industryFluidized bed coal combustion

New kind of fly ashCirculating Fluidized Bed Combustion Fly Ash

CFBCFA


CFBCFA

Fluidized fly ash, what is it? 3

CFBC fly ashConventional fly ash

• Temp. of combustion ok. 850ºC

G i h i l

• Temp. of combustion ok. 1400ºC

G i h i l • Grains non-spherical

• Glassy phase is not present

• Grains spherical

• Glassy phase is present


Fluidized fly ash, what is it?

Properties of CFBCFA:

4

• high content of different calcium sulphur compounds• high content of free lime

Properties of CFBCFA:

• high content of free lime• higher loss of ignition compared to standard fly ash


5Fluidized fly ash, what is it?

Circulating Fluidized Bed Combustion Fly Ash does not meet the requirements defined by European Standard EN 450 or t e equ e e ts de ed by u opea Sta da d 50 oASTM C618 to be used for cement or concrete production

CFBC FA does not conform to standard requirements as a concrete additive

Accordingly, it has to be treated on a case-by-case basis in relation to its applicationrelation to its application


Fluidized fly ash – current applications

C t li ti f fl idi d fl h

6

Current applications of fluidized fly ashin the infrastructure:

Hi h i i d d t ti ( t bili• Highway engineering and road construction (a stabilizer -

soil reinforcement by injection at the site)

• Geotechnics (hardening slurries)

• Hydrotechnics (filter diaphragms in soil foundations

protecting underground water against contamination)

also

• Filling underground structures (old coal mines) in land

reclamation


reclamation

• Macro levelling

Soil stabilization by means of 'jetgrouting‘ method with application of

7Fluidized fly ash – current applications

y j g g pp

Flubet® (mechanically activated CFBCFA) at the A4 highway section near

Ruda Śląska


Glinicki, Nowak, Maslanka

Crevice ditch with slurry containing

8Fluidized fly ash – current applications

Crevice ditch with slurry containing

Flubet® (mechanically activated CFBCFA)


Glinicki, Nowak, Maslanka

9

Portland cement concretes with addition of

GRANT 2006-2010

Portland cement concretes with addition of fluidized bed combustion fly ashesProject 2006-2010Project 2006-2010

Research project is oriented at determination whether and how CFBC flyResearch project is oriented at determination whether and how CFBC fly ash may be used as partial replacement for Portland cement in structural

concretes

Arguments for such investigation:- reduction of waste material deposits

Sustainable development

p- replacement of Portland cement (lower cost and reduction of powder and gas


emissions related to cement production)

R h j 2006 2010

GRANT 2006-2010 10

Research project 2006 – 2010

mixture composition and workability

mechanical properties (strength, Young’s modulus, etc.)

stability of the pore microstructure in the fresh mix

resistance against carbonation

corrosion of steel reinforcement

resistance against chloride ions penetration

frost resistance and scaling resistance

bond to steel and non-metallic reinforcement


GRANT 2006-2010 11

Mixture composition

Concrete A, ordinary concrete - XC3, XD2, XF1, XA1

Concrete B, high strength concrete - XC4, XD3, XF1, XA1

Concrete C, air-entrained concrete for bridges - XC4, XD3, XF4

XCXC -- corrosion caused by carbonationcorrosion caused by carbonationXDXD -- corrosion caused by chlorides not originated from seacorrosion caused by chlorides not originated from sea--waterwaterXFXF –– frostfrost--saltsalt aggressionaggressionXAXA -- chemically aggressive environmentchemically aggressive environment


GRANT 2006-2010

Mixture composition

12

A B C

Mixture composition

A B C

OC HSC air-entrained

w/b = 0.55 w/b = 0.45 w/b = 0.45

C=320 kg/m3 C=360 kg/m3 C=380 kg/m3g/ g/ g/

l f 0% % d 30% f b C CReplacement of 0%, 15% and 30% of cement mass by CFBC

fly ash from hard coal and from lignite


GRANT 2006-2010, Examples of test results – Compressive strength

A0 B0 C0

13


w/b = 0.55 w/b = 0.45 w/b = 0.45

Betony A - rozwój wytrzymałości na ściskanie

60

70

80

anie

[MP

a]

Betony B - rozwój wytrzymałości na ściskanie

60

70

80an

ie [M

Pa]

Betony C - rozwój wytrzymałości na ściskanie

60

70

80

nie

[MP

a]

fc [MPa] fc [MPa] fc [MPa]

fcA020

30

40

50

wyt

rzym

ałość

na ś

cisk

a

20

30

40

50

ytrz

ymał

ość

na ś

cisk

a

20

30

40

50

ytrz

ymał

ość

na ś

cisk

a

fcA0 fcA15K fcA30K fcA15T fcA30T

0 60 120 180 240 300 360czas dojrzewania [dni]

10

w fcB0 fcB15K fcB30K fcB15T fcB30T


10

wy

fcC0 fcC15K fcC30K fcC15T fcC30T


10

wy

Maturity period [days] Maturity period [days] Maturity period [days]


max: A15T min: A0 i A15K

max: B0 i B15T min: B30K

max: C30K min: C30T

Śliwiński et al.

A0 B0 C0

GRANT 2006-2010, Examples of test results – THIN SECTIONS 14


w/b = 0.55 w/b = 0.45 w/b = 0.45

PLANE POLARIZED LIGHTblue dye, magnification 40x


GRANT 2006-2010, Examples of test results – THIN SECTIONS 15

A15T A15KA15T

A30T A30K


15% and 30% of lignite 15% and 30% of hard coal

GRANT 2006-2010, Examples of test results – THIN SECTIONS

A30K

16

30% of hard coal

A30TA30T30% of lignite30% of lignite

Unburned coal particles


17GRANT 2006-2010, Examples of test results – THIN SECTIONS

PLANE POLARIZED LIGHTyellow dye, magnification 40x

Air entrained concretes w/b 0 45

C0, without CFBCFA C30K, 30% of CFBCFA from hard coal

Air-entrained concretes, w/b = 0.45

C0, t out C C C30K, 30% of CFBCFA from hard coal



UV LIGHTyellow dye, magnification 40x

Air entrained concretes w/b 0 45Air-entrained concretes, w/b = 0.45

C0, without CFBCFA C30K, 30% of CFBCFA from hard coalC0, t out C C C30K, 30% of CFBCFA from hard coal


Test of air content in fresh mix revealed a proportional increase of the dosage of AEA, to achieve the target air content (6%), along with increasing content of

19GRANT 2006-2010, Examples of test results – microstructure of air voids

The spacing factor of air void system vs the content of CFBCFA

AEA, to achieve the target air content (6%), along with increasing content of CFBCFA

Spacing factor L, mm

Content of CFBCFA, %

The content of CFBCFA > 30% strongly influences on the microstructure of air-voids by missing the micro pores which play the major role in the frost


Glinicki, Zielińskiresistance of concrete


C30K 30% f CFBCFA f h d l

UV LIGHT, yellow dye, magnification 40xC30K, 30% of CFBCFA from hard coal


Crossed polarized light, yellow dye, magnification 40x


1.2 mm

C30K, 30% of CFBCFA f h d l

2 mmfrom hard coal


Carbonation zoneC0, without CFBCFA

EN 13295:2004

GRANT 2006-2010, Examples of test results – carbonation 22

specimens 100x100 mm, 1% CO2

0.55/30K = w/b=0.55, 30% of CFBCFA from hard coal0 45/15T w/b 0 45 15% of CFBCFA from brown coal

10

12

m

0,55/30K

0,55/15K

0.45/15T = w/b=0.45, 15% of CFBCFA from brown coal

6

8

0

onat

ion,

mm 0,55/30T

0,55/15T

0,55/0

4

6

eep

of c

arbo 0,45/30T

0,45/30K

0,45/0

0

2

14 28 56 90

de

0,45/0

0,45/15K

0,45/15T


14 28 56 90age, days

Czarnecki, Woyciechowski

GRANT 2006-2010, Examples of test results – scaling resistance

h d lCEN/TS 12390-9:2007, slab test

23

1,4

scaling [kg/m2]

30%K

K - Katowice, hard coal

T - Turów, lignite

30%T

0 8

1,0

1,2

critical value

30%K 30%T

0,4

0,6

0,8

15%K15%T

0,0

0,2

0 7 14 21 28 35 42 49 56

0%

0 7 14 21 28 35 42 49 56number of cycles [days]

Scaling resistance is decreasing with increased CFBCFA content


g gand unburned carbon content

GRANT 2006-2010, Examples of test results – chloride ions penetration

Nordtest Method BUILD 492

24

14

16

18

28 dni 90 dni 180 dni

6

8

10

12

14D

, x10

-12

m2/

s

w/b = 0.45non air-

entrained

0

2

4

6

B0 B15K B15T B30K B30T

K - hard coal T - lignite

entrained concretes

12

14

16

18

2/s

28 dni 90 dni 180 dni

T lignite

2

4

6

8

10

D, x

10-1

2 m

2

air-entrained concretes


0

2

C0 C15K C15T C30K C30T

Results – resistivity

GRANT 2006-2010, Examples of test results – resistivity 25

y

resistivity [k om cm] (K) Katowice - hard coal(T) Turów brown coal

150

180

30%K

(T) Turów - brown coal

90

12030%K30%T

15%K

30

6015%K15%T

0%0

20 40 60 80 100 120 140 160 180

0%


time [days]

26

Conclusions:

Conclusions

Positive effects:• Increase of long term compressive strength by 10% CFBCFA h• Increase of long term compressive strength by 10%

• Non-steady chloride migration coefficient is decreasing

with CFBCFA content

C t i ti it i i i ith CFBCFA t t

CFBCFA has compacted the microstucture

of concrete• Concrete resistivity is increasing with CFBCFA content

Negative effects:Negative effects:• Scaling resistance is decreasing with increased CFBCFA content and

unburned carbon

Addition of CFBCFA slightly increases the depth of carbonation• Addition of CFBCFA slightly increases the depth of carbonation

• Required microstructure of air entrained voids is more difficult to be

obtained but possible


Conclusions:

Conclusions 27

Conclusions:

After preliminary test results it seemsAfter preliminary test results, it seems admissible to use Circulating Fluidized Bed C b ti Fl A h f t t l tCombustion Fly Ash for structural concretes, with some restrictions


28

Thank you for attention


the application of fluidized fly ash a new kind of waste material...

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