Characteristics of CFBC fly ash and properties of cement-based composites with CFBC fly ash and coal-fired fly ash

Circulating fluidized bed combustion (CFBC) fly ash is a promising admixture for construction and building materials due to its pozzolanic activity and self-cementitious property. In this study, CFBC fly ash and coal-fired fly ash were used in Portland cement to investigate the pozzolanic and cementitious characteristics of CFBC fly ash and the properties of cement-based composites. Tests show that CFBC fly ash has the potential instead of cementing materials and as an alternative of pozzolan. In fresh specimens, the initial setting time of mortars increases with the increasing amount of cement replacement by CFBC fly ash and coal-fire fly ash. In harden specimens, adding CFBC fly ash to replace OPC reduces the compressive strength. Meanwhile, CFBC fly ash would results in a higher length change when adding over 30%. Based on the results, the amount of CFBC fly ash replacement cement was recommended to be limited below 20%.

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Performance and Microstructural Evaluation of Rice Husk Ash–Ground Granulated Blast Furnace Slag–CFBC Fly Ash Mixtures Produced as an Eco-Cement

Journal of Materials in Civil Engineering ◽

10.1061/(asce)mt.1943-5533.0004119 ◽

2022 ◽

Vol 34 (3) ◽

Author(s):

Phuong-Trinh Bui ◽

Trong-Phuoc Huynh

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Rice Husk ◽

Blast Furnace Slag ◽

Rice Husk Ash ◽

Granulated Blast Furnace Slag ◽

Microstructural Evaluation ◽

Cfbc Fly Ash ◽

Furnace Slag

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Chemical Properties and Reactivity of CFBC Fly Ash

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.722.132 ◽

2016 ◽

Vol 722 ◽

pp. 132-139 ◽

Cited By ~ 1

Author(s):

Tomáš Váchal ◽

Rostislav Šulc ◽

Tereza Janků ◽

Pavel Svoboda

Keyword(s):

Thermal Properties ◽

Fly Ash ◽

Circulating Fluidized Bed ◽

Chemical Properties ◽

Total Content ◽

Calorimetric Measurement ◽

Fluidized Bed Combustion ◽

Cfbc Fly Ash ◽

Circulating Fluidized Bed Combustion ◽

Methods Of Measurement

This paper describes chemical properties of fly ash from Circulating fluidized Bed Combustion (CFBC). There are shown thermal properties of fly ash using calorimetric measurement and the total content of calcium oxide CaO was determined. This paper describes the methods of measurement for determining these properties including granulometric measurement and chemical analysis. Also there were described and evaluated properties of fly ash and the reactivity of the fly ash was compared.

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Influence of Mechanically-Treatment on Physical-Chemical Properties of Circulation Fluidized Bed Combustion Fly Ash

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.509.181 ◽

2012 ◽

Vol 509 ◽

pp. 181-188 ◽

Cited By ~ 1

Author(s):

De Yu Chen ◽

Yun Yan ◽

Yuan Zheng Liu ◽

Meng Huang

Keyword(s):

Fly Ash ◽

Fluidized Bed ◽

Water Demand ◽

Fine Particles ◽

Chemical Properties ◽

Fluidized Bed Combustion ◽

Volume Stability ◽

The Matrix ◽

Cfbc Fly Ash ◽

Grinding Time

The comprehensive performance, such as water demand, hydration heat, expansion, and self-hardening of circulation fluidized bed combustion (CFBC) fly ash ground by the laboratory mill were studied in this paper. Results show that the percentage of fine particles and fluidity of CFBC fly ash increased with grinding time. However, the water demand at normal consistency of the CFBC ash decreased with grinding time. The hydration exothermic rate of the paste has been accelerated and the time of reaching the volume stability has been shortened. Meanwhile, the compressive strength of the paste and the content of ettringite in the matrix increased with the curing time in the early age, but reversed later.

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Unburned carbon in the circulating fluidised bed boiler fly ash

Chemical and Process Engineering ◽

10.2478/v10176-011-0020-8 ◽

2011 ◽

Vol 32 (4) ◽

pp. 255-266 ◽

Cited By ~ 4

Author(s):

Rafał Kobyłecki

Keyword(s):

Fly Ash ◽

Separation Efficiency ◽

Unburned Carbon ◽

Fuel Particle ◽

Fluidised Bed ◽

Bed Temperature ◽

Grid Design ◽

Cfbc Fly Ash ◽

Boiler Fly Ash ◽

Circulating Fluidised Bed

Unburned carbon in the circulating fluidised bed boiler fly ash The paper describes the results of various actions and industrial tests conducted in order to decrease the content of unburned carbon in the fly ash of a circulating fluidised bed combustor (CFBC). Several attempts to improve the situation were made and the effects of several parameters on the unburned carbon content in the fly ash were investigated (e.g. bed temperature, cyclone separation efficiency, fuel particle size distribution, boiler hydrodynamics, grid design, and fuel data). Unfortunately, no satisfactory solution to these problems was found. Probably, apart from attrition and char fragmentation, additional factors also contributed to the formation of unburned carbon in the CFBC fly ash.

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