Abstract
Geopolymer cements exhibit high-strength properties while producing ~60% lower
CO2
emissions compared with Portland cement manufacture. Much of this offset has
been achieved by the use of waste based materials like Fly Ash and GGBS. These
pozzolanic materials are becoming increasingly scarce and expensive limiting the
expansion of these low carbon alternatives.
A number of new waste derived materials have been identified for use as Geopolymer
feedstocks including historic slags, dredgings, bottom ashes, waste clays and mine
tailings. This paper reviews these alternative waste based feedstocks and their role
within a circular economy. The chemical composition and properties of these materials,
as well as the factors that affect the performance of geopolymer cements made from
them are compared. Key factors are shown to be the Si and Al presence and ratio and
the availibility of alkaline cations (Na+, K+, Ca+2). A number of deterious componets
common in these alternative wastes are identified including presence of organic matter
and chlorides.
A case study evaluating the use of treated municipal soil waste from construction sites
is presented utilising filter cake produced in Teesside (UK). A digital Taguchi design
matrix was established to identify significant variables in the final geopolymer UCS,
this included soil chemistry, water content and alkali components. The maximum UCS
recorded across all geopolymer mixtures was 25 MPa.
The paper concludes that alternative, circular waste based feedstocks have the potential
to be used to produce high-performance geopolymer cements. However, further
research is needed to pre-treat these materials and to develop cost-effective, consistent
and scalable production methods.
CO2
emissions compared with Portland cement manufacture. Much of this offset has
been achieved by the use of waste based materials like Fly Ash and GGBS. These
pozzolanic materials are becoming increasingly scarce and expensive limiting the
expansion of these low carbon alternatives.
A number of new waste derived materials have been identified for use as Geopolymer
feedstocks including historic slags, dredgings, bottom ashes, waste clays and mine
tailings. This paper reviews these alternative waste based feedstocks and their role
within a circular economy. The chemical composition and properties of these materials,
as well as the factors that affect the performance of geopolymer cements made from
them are compared. Key factors are shown to be the Si and Al presence and ratio and
the availibility of alkaline cations (Na+, K+, Ca+2). A number of deterious componets
common in these alternative wastes are identified including presence of organic matter
and chlorides.
A case study evaluating the use of treated municipal soil waste from construction sites
is presented utilising filter cake produced in Teesside (UK). A digital Taguchi design
matrix was established to identify significant variables in the final geopolymer UCS,
this included soil chemistry, water content and alkali components. The maximum UCS
recorded across all geopolymer mixtures was 25 MPa.
The paper concludes that alternative, circular waste based feedstocks have the potential
to be used to produce high-performance geopolymer cements. However, further
research is needed to pre-treat these materials and to develop cost-effective, consistent
and scalable production methods.
| Original language | English |
|---|---|
| Pages | 12 |
| Number of pages | 1 |
| Publication status | Published - 30 Nov 2023 |
| Event | International Conference on Ceramics and Geomaterials in Central Africa : Georesources for Ceramics: Energetic Transition, Water Treatment, and Artificial Intelligence - Faculty of Science of the University of Yaoundé, Yaoundé, Cameroon Duration: 28 Nov 2023 → 1 Dec 2023 https://www.cacers.org/events/cgca-01/?lang=en#:~:text=AND%20ARTIFICIAL%20INTELLIGENCE-,About%20CGCA%2D01,%2C%20the%20%5B...%5D |
Conference
| Conference | International Conference on Ceramics and Geomaterials in Central Africa |
|---|---|
| Abbreviated title | CGCA-01 |
| Country/Territory | Cameroon |
| City | Yaoundé |
| Period | 28/11/23 → 1/12/23 |
| Other | This first edition of the International Conference on Ceramics and Geomaterials in Central Africa (CGCA-01) will be held in Yaoundé (Cameroon) on November 28 – December 1, 2023. It is organized by the Institute of Research for Ceramics (IRCER, CNRS and University of Limoges), the Faculty of Science of the University of Yaoundé I (Yaoundé, Cameroon) and the MIPROMALO research center (Yaoundé, Cameroon) and occurs under the auspices of the newly created Composites and Advanced Ceramic Society (CACerS) in Central Africa. The main target of CGCA 01 will be to highlight the main answers that can bring sustainable and innovative ceramic solutions to some critical societal challenges. CGCA-01 will include plenary and invited talks, oral presentations, a poster session and a round table. The eight topics covered by CGCA-01 are listed below: Geomaterials and clays: prospections and characterization; Ceramics and geomaterials processing; Sintering and consolidation mechanisms Characterization, Structure – properties correlation; Low carbon materials, Environmentally Friendly Materials and Sustainability; Waste valorization and recycling; Porous ceramics and clay-based materials; Properties of use and Industrial applications; Modelling and Artificial intelligence for materials science. The debate (round table) will be conducted on the topic “Artificial intelligence, modelling and Circular Economy in material science in Africa”. Recognitions (engagement) and awards (selection by a jury) will be attributed during this conference. Conference language: English, except for plenary and invited talk (choice between French and English) Estimated number of participants: > 150 |
| Internet address |