ENHANCING THE REACTIVITY OF THE INDUSTRIAL FLY ASH IN THE PROCESS OF ALKALI ACTIVATION
Апстракт
Over the past few decades a new group of binding materials, geopolymers, have
emerged as an alternative to traditional binding materials such as Portland cement.
Geopolymers are obtained by the process of alkali activation of various alumino-
silicate materials, both natural and synthetic. Of particular importance is the
possibility of alkali activation of the industrial waste material such as fly ash. Fly
ash (FA) is generated in the process of coal combustion in thermal power plants. In
Serbia a small part of fly ash is recycled while the rest is landfilled, causing a
serious environmental pollution. Alkali activation represents a process by which fly
ash can safely be converted into a useful biding material, suitable for the
construction purposes. Geopolymers (or alkali-activated materials) based on fly ash
are known for their good compressive strength and good durability in aggressive
environments, when propeerly designed. However, the limiting factor for wider use
of f...ly ash in the process of alkali activation and geopolymers synthesis is its low
reactivity and consequent low compressive strength of binding elements. Our
research has shown that the reactivity of fly ash in the process of alkali activation
can be enhanced by the appropriate choice of the reaction conditions – by
mechanical activation of fly ash and by blending with more reactive material such as
blast furnace slag (BFS). Both options were explored in this paper and comparison
was performed. Mechanical activation of fly ash was conducted in a planetary ball
mill, while blends of fly ash and blast furnace slag were prepared with different
ratios (FA/(FA+BFS) = 1; 0,75; 0,50; 0,25; 0). Alkali activation was carried out at
95ºC by use of sodium silicate solution as an activator. In both cases significant
increase of geopolymer compressive strength was observed in respect to the
geopolymer based on the initial fly ash. Optimal geopolymer strength was correlated
with the chemical composition of the binding gel. Empirical values of optimal gel
composition could serve as a basis for tailoring properties of alkali-activated binders
based on different precursors. Both alkali-activated systems represent promissing
routes for geopolymer technology development.
Кључне речи:
fly ash / blast furnace slag / mechanical activation / alkali activationИзвор:
7th Conference of The Serbian Society for Ceramic Materials, 2023Издавач:
- Institut za multidisciplinarna istraņivanja Kneza Vińeslava 1, 11000 Belgrade, Serbia
Институција/група
Institut za multidisciplinarna istraživanjaTY - CONF AU - Džunuzović, Nataša AU - Komljenović, Miroslav M AU - Nikolić, Violeta AU - Baščarević, Zvezdana PY - 2023 UR - http://rimsi.imsi.bg.ac.rs/handle/123456789/2439 AB - Over the past few decades a new group of binding materials, geopolymers, have emerged as an alternative to traditional binding materials such as Portland cement. Geopolymers are obtained by the process of alkali activation of various alumino- silicate materials, both natural and synthetic. Of particular importance is the possibility of alkali activation of the industrial waste material such as fly ash. Fly ash (FA) is generated in the process of coal combustion in thermal power plants. In Serbia a small part of fly ash is recycled while the rest is landfilled, causing a serious environmental pollution. Alkali activation represents a process by which fly ash can safely be converted into a useful biding material, suitable for the construction purposes. Geopolymers (or alkali-activated materials) based on fly ash are known for their good compressive strength and good durability in aggressive environments, when propeerly designed. However, the limiting factor for wider use of fly ash in the process of alkali activation and geopolymers synthesis is its low reactivity and consequent low compressive strength of binding elements. Our research has shown that the reactivity of fly ash in the process of alkali activation can be enhanced by the appropriate choice of the reaction conditions – by mechanical activation of fly ash and by blending with more reactive material such as blast furnace slag (BFS). Both options were explored in this paper and comparison was performed. Mechanical activation of fly ash was conducted in a planetary ball mill, while blends of fly ash and blast furnace slag were prepared with different ratios (FA/(FA+BFS) = 1; 0,75; 0,50; 0,25; 0). Alkali activation was carried out at 95ºC by use of sodium silicate solution as an activator. In both cases significant increase of geopolymer compressive strength was observed in respect to the geopolymer based on the initial fly ash. Optimal geopolymer strength was correlated with the chemical composition of the binding gel. Empirical values of optimal gel composition could serve as a basis for tailoring properties of alkali-activated binders based on different precursors. Both alkali-activated systems represent promissing routes for geopolymer technology development. PB - Institut za multidisciplinarna istraņivanja Kneza Vińeslava 1, 11000 Belgrade, Serbia C3 - 7th Conference of The Serbian Society for Ceramic Materials T1 - ENHANCING THE REACTIVITY OF THE INDUSTRIAL FLY ASH IN THE PROCESS OF ALKALI ACTIVATION UR - https://hdl.handle.net/21.15107/rcub_rimsi_2439 ER -
@conference{ author = "Džunuzović, Nataša and Komljenović, Miroslav M and Nikolić, Violeta and Baščarević, Zvezdana", year = "2023", abstract = "Over the past few decades a new group of binding materials, geopolymers, have emerged as an alternative to traditional binding materials such as Portland cement. Geopolymers are obtained by the process of alkali activation of various alumino- silicate materials, both natural and synthetic. Of particular importance is the possibility of alkali activation of the industrial waste material such as fly ash. Fly ash (FA) is generated in the process of coal combustion in thermal power plants. In Serbia a small part of fly ash is recycled while the rest is landfilled, causing a serious environmental pollution. Alkali activation represents a process by which fly ash can safely be converted into a useful biding material, suitable for the construction purposes. Geopolymers (or alkali-activated materials) based on fly ash are known for their good compressive strength and good durability in aggressive environments, when propeerly designed. However, the limiting factor for wider use of fly ash in the process of alkali activation and geopolymers synthesis is its low reactivity and consequent low compressive strength of binding elements. Our research has shown that the reactivity of fly ash in the process of alkali activation can be enhanced by the appropriate choice of the reaction conditions – by mechanical activation of fly ash and by blending with more reactive material such as blast furnace slag (BFS). Both options were explored in this paper and comparison was performed. Mechanical activation of fly ash was conducted in a planetary ball mill, while blends of fly ash and blast furnace slag were prepared with different ratios (FA/(FA+BFS) = 1; 0,75; 0,50; 0,25; 0). Alkali activation was carried out at 95ºC by use of sodium silicate solution as an activator. In both cases significant increase of geopolymer compressive strength was observed in respect to the geopolymer based on the initial fly ash. Optimal geopolymer strength was correlated with the chemical composition of the binding gel. Empirical values of optimal gel composition could serve as a basis for tailoring properties of alkali-activated binders based on different precursors. Both alkali-activated systems represent promissing routes for geopolymer technology development.", publisher = "Institut za multidisciplinarna istraņivanja Kneza Vińeslava 1, 11000 Belgrade, Serbia", journal = "7th Conference of The Serbian Society for Ceramic Materials", title = "ENHANCING THE REACTIVITY OF THE INDUSTRIAL FLY ASH IN THE PROCESS OF ALKALI ACTIVATION", url = "https://hdl.handle.net/21.15107/rcub_rimsi_2439" }
Džunuzović, N., Komljenović, M. M., Nikolić, V.,& Baščarević, Z.. (2023). ENHANCING THE REACTIVITY OF THE INDUSTRIAL FLY ASH IN THE PROCESS OF ALKALI ACTIVATION. in 7th Conference of The Serbian Society for Ceramic Materials Institut za multidisciplinarna istraņivanja Kneza Vińeslava 1, 11000 Belgrade, Serbia.. https://hdl.handle.net/21.15107/rcub_rimsi_2439
Džunuzović N, Komljenović MM, Nikolić V, Baščarević Z. ENHANCING THE REACTIVITY OF THE INDUSTRIAL FLY ASH IN THE PROCESS OF ALKALI ACTIVATION. in 7th Conference of The Serbian Society for Ceramic Materials. 2023;. https://hdl.handle.net/21.15107/rcub_rimsi_2439 .
Džunuzović, Nataša, Komljenović, Miroslav M, Nikolić, Violeta, Baščarević, Zvezdana, "ENHANCING THE REACTIVITY OF THE INDUSTRIAL FLY ASH IN THE PROCESS OF ALKALI ACTIVATION" in 7th Conference of The Serbian Society for Ceramic Materials (2023), https://hdl.handle.net/21.15107/rcub_rimsi_2439 .