Pozzolanic reactivity of aluminum-rich sewage sludge ash: Influence of calcination process and effect of calcination products on cement hydration

Chang, Z; Long, G; Xie, Y; Zhou, JL

Pozzolanic reactivity of aluminum-rich sewage sludge ash: Influence of calcination process and effect of calcination products on cement hydration

Chang, Z Long, G Xie, Y Zhou, JL

Permalink

Publisher:: ELSEVIER SCI LTD
Publication Type:: Journal Article
Citation:: Construction and Building Materials, 2022, 318
Issue Date:: 2022-02-07

Open Access

Copyright Clearance Process

Recently Added
In Progress
Open Access

This item is open access.

The embargo period expires on 1 Feb 2024

Adobe PDF

Download Accepted versionAdobe PDF (1.6 MB)

View on publisher's site

View statistics

Full metadata record

Field	Value	Language
dc.contributor.author	Chang, Z
dc.contributor.author	Long, G
dc.contributor.author	Xie, Y
dc.contributor.author	Zhou, JL
dc.date.accessioned	2023-03-24T04:03:27Z
dc.date.available	2023-03-24T04:03:27Z
dc.date.issued	2022-02-07
dc.identifier.citation	Construction and Building Materials, 2022, 318
dc.identifier.issn	0950-0618
dc.identifier.issn	1879-0526
dc.identifier.uri	http://hdl.handle.net/10453/168324
dc.description.abstract	The application of aluminum-based flocculant in wastewater treatment results in a large amount of aluminum-rich sewage sludge. This work investigated the influence of calcination process on physicochemical characteristics and pozzolanic activity of aluminum (Al)-rich sludge ash and studied the effect of sludge ash on cement hydration. The results showed that higher calcination temperature from 600 ℃ to 900 ℃ increased the amorphous content in sludge ash. The pozzolanic activity of sludge ash calcined at 800 ℃ and 900 ℃ was confirmed by Frattini test. In view of strength activity index of blended mortar and energy conservation, the optimal calcination condition of sewage sludge ash was calcined at 800 ℃ with air-cooling. The addition of sludge ash promoted the transformation of ettringite to monosulfate phase in cement paste. However, the high Al concentration dissolved from S6 and S7 ash inhibited significantly the cement hydration and resulted in low compressive strength values of the blended mortars. The pozzolanic reaction of S8 and S9 ash produced more hydration heat and additional Al-bearing products such as katoite and monosulfate which contributed to the strength development of mortars. Furthermore, the heavy metals in sewage sludge can be immobilized in ash structure during calcination process and the structure of hydration products, which ensures the environmental security of sludge ash utilization in construction materials.
dc.language	English
dc.publisher	ELSEVIER SCI LTD
dc.relation.ispartof	Construction and Building Materials
dc.relation.isbasedon	10.1016/j.conbuildmat.2021.126096
dc.rights	info:eu-repo/semantics/embargoedAccess
dc.subject	0905 Civil Engineering, 1202 Building
dc.subject.classification	Building & Construction
dc.title	Pozzolanic reactivity of aluminum-rich sewage sludge ash: Influence of calcination process and effect of calcination products on cement hydration
dc.type	Journal Article
utslib.citation.volume	318
utslib.for	0905 Civil Engineering
utslib.for	1202 Building
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Engineering and Information Technology
pubs.organisational-group	/University of Technology Sydney/Faculty of Engineering and Information Technology/School of Civil and Environmental Engineering
pubs.organisational-group	/University of Technology Sydney/Strength - CTWW - Centre for Technology in Water and Wastewater Treatment
utslib.copyright.status	open_access	*
utslib.copyright.embargo	2024-02-01T00:00:00+1000Z
dc.date.updated	2023-03-24T04:03:26Z
pubs.publication-status	Published
pubs.volume	318

Abstract:

The application of aluminum-based flocculant in wastewater treatment results in a large amount of aluminum-rich sewage sludge. This work investigated the influence of calcination process on physicochemical characteristics and pozzolanic activity of aluminum (Al)-rich sludge ash and studied the effect of sludge ash on cement hydration. The results showed that higher calcination temperature from 600 ℃ to 900 ℃ increased the amorphous content in sludge ash. The pozzolanic activity of sludge ash calcined at 800 ℃ and 900 ℃ was confirmed by Frattini test. In view of strength activity index of blended mortar and energy conservation, the optimal calcination condition of sewage sludge ash was calcined at 800 ℃ with air-cooling. The addition of sludge ash promoted the transformation of ettringite to monosulfate phase in cement paste. However, the high Al concentration dissolved from S6 and S7 ash inhibited significantly the cement hydration and resulted in low compressive strength values of the blended mortars. The pozzolanic reaction of S8 and S9 ash produced more hydration heat and additional Al-bearing products such as katoite and monosulfate which contributed to the strength development of mortars. Furthermore, the heavy metals in sewage sludge can be immobilized in ash structure during calcination process and the structure of hydration products, which ensures the environmental security of sludge ash utilization in construction materials.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/168324