Recovery of Sewage Sludge Incinerator Ash by Geopolymerizationuest.ntua.gr/heraklion2019/proceedings/Presentation/6.G.SALIHOGLU.pdf · B Sludge Ash C Marble Sludge D Ac tivaor Factor

Recovery of Sewage Sludge Incinerator Ash by Geopolymerization

B. Yigit, G. Salihoglu*, A. Mardani-Aghabaglou, S. Kilic, N.K. Salihoglu, S. Ozen

Department of Environmental Engineering, Bursa Uludağ University, Bursa, 16059, TURKEY

Department of Civil Engineering, Bursa Uludağ University, Bursa, 16059, TURKEY

7TH INTERNATIONAL CONFERENCE ON SUSTAINABLE SOLID WASTE MANAGEMENT, 28-29 June 2019, Crete Island

0103

0204

Incineration

Sludge Management

in waste management

Geopolymers

Samples & Analyses

Materials & Methods

Leaching & UCSResults

Content



Sludge Generation & Incineration

Volume of the sludge decreases, ashes are generated.

Increasing population & Increasing amount of

sludgeIncineration: gained

attention as a common disposal

method

«Nothing vanishes, everything transforms»

Gas (Emissions)

Liquid (Water vapor)

Solid (ASH)


Incineration Plant & Sludge Ashes

Capacity : 400 tons sludge/day

Fluidized bed incinerator of Bursa

city

15-20 tons fly ash/day

Ash brings a

waste

management

problem.

Ash brings a

waste

management

problem.

Landflling is not

sustainable!Landflling is not

sustainable!

Multi-cyclone dust collector


Objective of the Study

To develop a recovery strategy for the sewage sludge incinerator ashes

by using

GEOPOLYMERIZATION

Geopolymers

01 02 03 04

Cementitiousmaterials that do not require the

presence of cement to harden

3d network of Si & Al mineral molecules linked through covalent bonds with oxygen molecules

Synthetic alkali-

aluminosilicate material

Physical & chemical

properties comparable to cementitious

binders7TH INTERNATIONAL CONFERENCE ON SUSTAINABLE SOLID WASTE MANAGEMENT, 28-29 June 2019, Crete Island


Geopolymers

Alumino-silicate source

Alkali Geopolymer paste

• Ground granulated blast furnace slag

• Silica fume• Coal combustion fly ash

Sludge incinerator

fly ash was used as

geopolymer

precursor in this

study.

Sludge incinerator

fly ash was used as

geopolymer

precursor in this

study.

• Alkalis and alkaline activators, e.g. NaOH, KOH, sodium/potassium silicates

Sludge ash

Binders: Portland cement,

fly ash, marble sludge Activators:

NaSilNaOH, water

Stabilization / Solidification

Geopolymerization

Air-cure (28

Days)

Leaching tests : EN

12457

Unconfined compressive

strength test (28 days air cure)

Evaluation

Construction material

Materials and Methods

Combinations were

prepared. Alumino-

silicate sources :

Sludge ash,

cement, fly ash,

marble sludge

Combinations were

prepared. Alumino-

silicate sources :

Sludge ash,

cement, fly ash,

marble sludge


Chemical composition of the materials

SiO2 contents are comparable (sludge ash

Cement)Fly ash with higher SiO2 Highest CaO with

marble sludge

Sludge ash had less CaO than

Cement


Parameter mg/LSilver (Ag) <0.003

Aluminum (Al) 0.053Arsenic (As) <0.012

Boron (B) 0.030Cadmium (Cd) <0.003

Total Chromium (Cr)

1.629

Copper (Cu) <0.003Total Ferrous

(Fe)<0.004

Manganese (Mn)

<0.005

Nickel (Ni) <0.005Lead (Pb) <0.012

Antimony (Sb) 0.018Tin (Sn) <0.009Zinc (Zn) 0.052

Selenium (Se) 0.026

Heavy metal leaching from the sludge ash (EN12457)

Leaching was

lower than the

limits:

Non-Hazardous

Waste

Leaching was

lower than the

limits:

Non-Hazardous

Waste


Cement

Fly ash

Sludge Ash

Marble Sludge

Activator

100% Water10% 30% 30% 30% Water40% 30% 30% Water40% 30% 30% Water70% 30% Water40% 30% 30% Water70% 30% Water70% 30% Water100% NaSilNaO

H10% 30% 30% 30% NaSilNaO

H40% 30% 30% NaSilNaO


H70% 30% NaSilNaO


H70% 30% NaSilNaO

H70% 30% NaSilNaO

H

S/S Samples:

Prepared with water

Geopolymer

samples:

Prepared with

NaSilNaOH

S/S Samples:

Prepared with water

Geopolymer

samples:

Prepared with

NaSilNaOHFly ashSludge Ash

Marble Sludge

40 20 4050 50

20 80100

80 20100

100

Content of the samples preparedSamples with cement

Samples without cement

Fly ash, sludge

ash, marble

sludge, cement

were used.

Fly ash, sludge

ash, marble

sludge, cement

were used.

Sludge ash

content:

Up to 30%

Cement: 10-100%

Sludge ash

content:

Up to 30%

Cement: 10-100%Sludge ash

content:

20%

Sludge ash

content:

20%


Results & Discussion

12.510.07.55.02.50.0-2.5-5.0

99

95

90

80

70

60

5040

30

20

10

5

1

A Fly ashB Sludge AshC Marble SludgeD Activator

Factor Name

Standardized Effect

Perc

ent

Not SignificantSignificant

Effect Type

ABC

BD

BC

AD

AC

AB

D

C

B

Normal Plot of the Standardized Effects(response is UCS, α = 0.05)

Combined influence of the parameters was signifcant.

Fly ash + Sludge ash + Marble sludge Fly ash + sludge

ash: UCS

decreasedFly ash + sludge

ash + marble sludge:

UCS increased

With the existence of NaSilNaOH

UCS increased


Main Effects

30%None

45

40

35

30

2530%None 30%None NaSilNaOHWater

Fly ash

Mea

n of

UCS

Sludge Ash Marble Sludge Activator

Main Effects Plot for UCSFitted MeansFly

ashSludge ash

Marble sludge

Activator

UC

S

None

30% None

30% None

30% None

30%

+ + +-

Fly ash and marble

sludge slightly

improved the UCS.

Sludge ash

decreased.

Fly ash and marble

sludge slightly

improved the UCS.

Sludge ash

decreased.


Unconfined Compressive Strength, MPa

Geopolymer UCS > S/S UCS

Sludge ash still can yield 46.70 MPa UCS: CEM+FA+SA

41.05 MPa UCS: CEM+FA+SA+MS

Negative influence

of sludge ash can

be balanced by

using fly ash and

marble sludge.

Negative influence

of sludge ash can

be balanced by

using fly ash and

marble sludge.

CEM: Portland cement, SA: sludge ash, FA: fly ash, MS: marble sludge


Unconfined Compressive Strength, Mpawithout cement

Geopolymer with cement UCS >

without cement

High UCS even without cement

(40,56 MPa)

Results imply that it is

possible to obtain high

UCS levels without

using cement, which

has a high carbon

footprint.

Results imply that it is

possible to obtain high

UCS levels without

using cement, which

has a high carbon

footprint.

ConclusionsCombined influence of sludge ash, fly ash, and marble sludge was positive although the influence of sludge ash alone was negative.UCS of SA+FA+MS = 40.56 MPa

Heavy metals leaching confrmed that sludge ash does not possess any toxicity leeaching.

Sludge incinerator fly ashes have the potential to be used as a supplementary cementitious material in geopolymerization.

01

0203

04




References 1. Khale, D., Chaudhary, R.: Mechanism of geopolymerization and factors influencing its development: a review. J Mater Sci 42(3), 729-746 (2007). doi:10.1007/s10853-006-0401-42. Komnitsas, K., Zaharaki, D.: Geopolymerisation: A review and prospects for the minerals industry. Miner Eng 20(14), 1261-1277 (2007). doi:10.1016/j.mineng.2007.07.0113. Davidovits, J.: Geopolymers - Inorganic Polymeric New Materials. J Therm Anal 37(8), 1633-1656 (1991). doi:Doi 10.1007/Bf019121934. Davidovits, J.: Geopolymer chemistry and applications. 2nd ed. 16 rue Galilee, 02100 Saint Quentin, France: Institute Geopolymere.. (2008). 5. Duxson, P., Fernandez-Jimenez, A., Provis, J.L., Lukey, G.C., Palomo, A., van Deventer, J.S.J.: Geopolymer technology: the current state of the art. J Mater Sci 42(9), 2917-2933 (2007). doi:10.1007/s10853-006-0637-z6. Duxson, P., Provis, J.L., Lukey, G.C., Van Deventer, J.S.J.: The role of inorganic polymer technology in the development of 'green concrete'. Cement Concrete Res 37(12), 1590-1597 (2007). doi:10.1016/j.cemconres.2007.08.0187. Toniolo, N., Boccaccini, A.R.: Fly ash-based geopolymers containing added silicate waste. A review. Ceramics International 43, 14545-14551 (2017). 8. Lynn, C.J., Dhir, R.K., Ghataora, G.S., West, R.P.: Sewage sludge ash characteristics and potential for use in concrete. Constr Build Mater 98, 767-779 (2015). doi:10.1016/j.conbuildmat.2015.08.1229. Monzo, J., Paya, J., Borrachero, M.V., Corcoles, A.: Use of sewage sludge ash(SSA)-cement admixtures in mortars. Cement Concrete Res 26(9), 1389-1398 (1996). doi:Doi 10.1016/0008-8846(96)00119-610. Monzo, J., Paya, J., Borrachero, M.V., Girbes, I.: Reuse of sewage sludge ashes (SSA) in cement mixtures: the effect of SSA on the workability of cement mortars. Waste Management 23(4), 373-381 (2003). doi:10.1016/S0956-053x(03)00034-511. Chen, C.H., Chiou, I.J., Wang, K.S.: Sintering effect on cement bonded sewage sludge ash. Cement Concrete Comp 28(1), 26-32 (2006). doi:10.1016/j.cemconcomp.2005.09.00312. Chen, M.Z., Denise, B., Mathieu, G., Jacques, M., Remy, G.: Environmental and technical assessments of the potential utilization of sewage sludge ashes (SSAs) as secondary raw materials in construction. Waste Management 33(5), 1268-1275 (2013). doi:10.1016/j.wasman.2013.01.00413. Lin, K.L., Chiang, K.Y., Lin, C.Y.: Hydration characteristics of waste sludge ash that is reused in eco-cement clinkers. Cement Concrete Res 35(6), 1074-1081 (2005). doi:10.1016/j.cemconres.2004.11.01414. Smol, M., Kulczycka, J., Henclik, A., Gorazda, K., Wzorek, Z.: The possible use of sewage sludge ash (SSA) in the construction industry as a way towards a circular economy. Journal of Cleaner Production 95, 45-54 (2015). doi:10.1016/j.jclepro.2015.02.05115. Wang, K.S., Chiou, I.J., Chen, C.H., Wang, D.: Lightweight properties and pore structure of foamed material made from sewage sludge ash. Constr Build Mater 19(8), 627-633 (2005). doi:10.1016/j.conbuildmat.2005.01.00216. Wiebusch, B., Seyfried, C.F.: Utilization of sewage sludge ashes in the brick and tile industry. Water Sci Technol 36(11), 251-258 (1997). doi:Doi 10.1016/S0273-1223(97)00688-4

Documents

Recovery of Sewage Sludge Incinerator Ash by Geopolymerizationuest.ntua.gr/heraklion2019/proceedings/Presentation/6.G.SALIHOGLU.pdf · B Sludge Ash C Marble Sludge D Ac tivaor Factor