Low CO2 Acid Base Binders Made with Fly Ash

Date

2016-12-11

Author

Erdoğan, Sinan Turhan

Metadata

Show full item record

Item Usage Stats

46
views

0
downloads

Portland cement (PC) is the ubiquitous binding material for constructions works in urban areas. It is, however, responsible for 5-10 % of all anthropogenic CO2 emissions, nearly half of which arise from the decomposition of calcareous raw materials, and the other half from kiln fuel combustion and cement clinker grinding operations. As such, PC production contributes to global warming and climate change. Lately, efforts to develop alternative binders with lower greenhouse gas emissions have gained interest. An important class of such binders is geopolymers, typically formed by activating natural or waste materials with suitable alkaline solutions. These binders can have very low CO2 emissions from grinding of the starting materials, and some from the production of the activating chemical but the total CO2 emissions can be as low as 1/5th - 1/10th of those of PC concrete mixtures with comparable properties. Less commonly researched, acidic activating chemicals can also be used with powder materials to produce pastes that can set and harden into durable solids. One such powder is fly ash from coal-burning power plants. This ash is mostly stockpiled and can be an environmental hazard such as exacerbating air pollution in cities. This study investigates the chemical activation of fly ashes from Turkey using solutions of acids such as orthophosphoric acid. Amorphous and crystalline reaction products are observed to form, yielding a strong binder that sets much more rapidly than PC-based mixtures or alkali-activated geopolymers. As the change in the rheological properties and mechanical properties of these pastes can be balanced by combining different ashes, as well as by adjusting solution properties, they can offer environmental, energetic, and economical advantages over conventional PC-based mixtures.

URI

https://hdl.handle.net/11511/77986

Conference Name

American Geophysical Union Fall Meeting 2016 (11 - 16 Aralık 2016)

Collections

Department of Civil Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Utilization of GGBFS blended cement pastes in well cementing Alp, Barış; Yaman, İsmail Özgür; Akın, Serhat; Department of Cement Engineering (2012) In well cementing, the cement slurry is exposed to the conditions far different than those of ordinary Portland cement (PC) used in construction. After placement, hardened cement paste should preserve integrity and provide zonal isolation through the life of the well. American Petroleum Institute (API) Class G cement is the most common cement type used in various well conditions. Class G cement has a high degree of sulfate resistance which makes it more stable than PC when subjected to the compulsive well c...
Synthesis of green calcium sulfoaluminate cements using an industrial symbiosis approach Tangüler Bayramtan, Meltem; Yaman, İsmail Özgür; Department of Civil Engineering (2022-9-1) Portland cement (PC), the main binder of concrete, is an energy- and emission-intensive construction material. Calcium sulfoaluminate (CSA) cement can be seen as a sustainable alternative to PC because its production uses less energy and emits less CO2 to the environment. A potential problem facing the production of CSA cement is the cost and availability of alumina-bearing raw materials like bauxite. In this study, it was aimed to synthesize environmentally friendly CSA cement using an industrial symbiosis...
High Performance Fiber Reinforced Concrete for Pavements Şengün, Emin; Alam, Burhan; Yaman, İsmail Özgür (2016-09-21) The addition of fibers has allowed concrete to take a role in the field of ductile materials. In this field, pavements were always a challenge and a success for concrete. To be a strong rival to asphalt, concrete needs to be more flexible, which is possible by the use of fibers. However, for this concrete pavement to be able to survive and last as long as possible it needs to be a high performance one. The shy use of concrete pavements in Turkey shows the need for further researches on the local base to all...
Rutting susceptibility of asphalt concrete with recycled concrete aggregate using revised Marshall procedure Gul, Waqar Ahmed; Güler, Murat (Elsevier BV, 2014-03-31) Natural aggregate is the primary ingredient of asphalt concrete and Portland cement concrete mixtures. Recycled concrete aggregate (RCA) derived from demolition wastes can be used in asphalt mixtures to eliminate potential problems arising from disposing these materials and conserve natural aggregate resources. This study presents methods for using RCA in asphalt mixtures based on repeated creep tests. The standard Marshall mixture design method is revised to prepare specimens satisfying the minimum size an...
QUANTIFICATION OF SEGREGATION IN PORTLAND CEMENT CONCRETE BASED ON SPATIAL DISTRIBUTION OF AGGREGATE SIZE FRACTIONS ÖZEN, MURAT; Güler, Murat (Slovenian Society for Stereology and Quantitative Image Analysis, 2020-01-01) Segregation is one of the quality standards that must be monitored during the fabrication and placement of Portland cement concrete. Segregation refers to separation of coarse aggregate from the cement paste, resulting in inhomogeneous mixture. This study introduces a digital imaging based technique to quantify the segregation of Portland cement concrete from 2D digital images of cut sections. In the previous studies, segregation was evaluated based on the existence of coarse aggregate fraction at different...

Citation Formats

S. T. Erdoğan, “Low CO2 Acid Base Binders Made with Fly Ash,” presented at the American Geophysical Union Fall Meeting 2016 (11 - 16 Aralık 2016), 2016, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/77986.