Assessments of Class F fly ashes for amelioration of soil acidity and their influence on growth and uptake of Mo and Se by canola

Fuel ◽  
2010 ◽  
Vol 89 (11) ◽  
pp. 3498-3504 ◽  
Author(s):  
V. Manoharan ◽  
I.A.M. Yunusa ◽  
P. Loganathan ◽  
R. Lawrie ◽  
C.G. Skilbeck ◽  
...  
Keyword(s):  
Soil Acidity ◽  
Fly Ashes ◽  
Amelioration Of Soil Acidity ◽  
Class F

Available Alkalis in Fly Ash

1985 ◽  
Vol 65 ◽  
Author(s):  
Chau Lee ◽  
Scott Schlorholtz ◽  
Turgut Demirel
Keyword(s):  
Fly Ash ◽  
Calcium Hydroxide ◽  
Fly Ashes ◽  
Class C ◽  
Time Required ◽  
Class F

ABSTRACTThe available alkalis of six Iowa fly ashes, four Class C and two Class F, have been studied as outlined by the procedures listed in ASTM C 311. The purposes of the study were to: (1) assess the significance of the test when it is used to analyze different fly ashes; (2) to investigate the possibility of decreasing the time required to complete the test (it currently requires 28 days for curing). When cured for 28 days at 38 C, the available alkalis were found to be about 60% and 30% of the total equivalent alkalis (equivalent alkalis = %Na20 + 0.658 × %K20) for Class C and Class F fly ashes, respectively. However, more than 85% and more than 40% of the total equivalent alkalis for the Class C and Class F fly ashes, respectively, were mobilized after 5 to 6 months of curing at 38 C. It was concluded that the available alkali test described in ASTM C 311 tends to underestimate the amount of equivalent alkalis present in Class C fly ash-calcium hydroxide mixtures after long periods of time.

The Diffusion of Chloride Ions in Fly Ash/Cement Pastes and Mortars

1986 ◽  
Vol 85 ◽  
Author(s):  
R. I. A. Malek ◽  
D. M. Roy ◽  
P. H. Licastro
Keyword(s):  
Fly Ash ◽  
Water Permeability ◽  
Electrical Potential ◽  
Chloride Ion ◽  
Chloride Ions ◽  
Basic Material ◽  
Fly Ashes ◽  
Cement Pastes ◽  
High Calcium ◽  
Class F

ABSTRACTFly ashes having three distinctly different levels of calcium, designated low-calcium (Class F), intermediate-calcium (Class F/C), and high-calcium (Class C), comprised the basic material for the present study. Pastes and mortars were made using cement and one of three types of fly ashes at various levels of replacement and water-solid ratios. Chloride ion diffusion was measured by applying an electrical potential across cured cylindrical samples and measuring the amount of current passed in a certain period of time (proportional to amount of CE” passed in this time). Other supportive measurements were made, e.g. porosity, pore size distribution, water permeability and surface area. The Cl− ion diffusivity was correlated with the chemical composition of fly ash, mix proportion, and water permeability of the hardened paste or mortar.

scholarly journals Separation of ultrafine particles from class F fly ashes

2016 ◽  
Vol 8 ◽  
pp. 01051
Author(s):  
Ilker Acar ◽  
Thomas L. Robl ◽  
M. Umit Atalay
Keyword(s):  
Ultrafine Particles ◽  
Fly Ashes ◽  
Class F

scholarly journals State-of-the-Art Report on Alkali Silica Reactivity Mitigation Effectiveness Using Different Types of Fly Ashes

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Enamur R. Latifee
Keyword(s):  
Fly Ash ◽  
State Of The Art ◽  
Oxide Content ◽  
Fly Ashes ◽  
Linear Effect ◽  
Alkali Silica Reactivity ◽  
Rapid Effect ◽  
Different Types ◽  
Class C ◽  
Class F

Use of fly ash by percent replacement of cement is considered as one of the most economical and effective methods for mitigating alkali-silica reaction (ASR) related distress in the concrete. However, fly ash has been proven to be somewhat variable in its effectiveness in inhibiting alkali-silica reactivity, principally because its composition depends on the coal properties from which it is derived. Typically class C fly ashes are not as efficient as class F ashes due to their higher calcium oxide content. Nevertheless, it is important to find out whether the lime content in the fly ash has linear effect on ASR distress mitigation and if the dosage of fly ash is more influential than type of fly ash. This research conducted extensive testing with nine different types of fly ashes with three in each category of fly ashes, class C, class F, and intermediate class. The results indicated that the effect of increased dosage of fly ash on ASR mitigation is linear for both low-lime and high-lime fly ashes and the dosage effect is more significant with rapid effect with high-lime fly ashes compared to low-lime fly ashes.

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