Production of ceramics from coal fly ash

Abstract

Dense ceramics are produced from fly ash from REK Bitola, Republic of Macedonia. Four types of fly ash from electro filters and one from the collected zone with particles < 0.063 mm were the subject of this research. Consolidation was achieved by pressing (P= 133 MPa) and sintering (950, 1000, 1050 and 11000C and heating rates of 3 and 100/min). Densification was realized by liquid phase sintering and solid state reaction where diopside [Ca(Mg,Al)(Si,Al)2O6] was formed. Ceramics with optimal properties (porosity 2.96±0.5%, bending strength - 47.01±2 MPa, compressive strength - 170 ±5 MPa) was produced at 1100ºC using the heating rate of 10ºC/min

Optimization of the Process of Production of Ceramics From Waste Coal Ash Case Study: The Influence of the Mechanical Activation

“…Investigation of the phase composition shows the presence of SiO 2 -quartz, CaAl 2 Si 2 O 8 -anorthite, Fe 2 O 3 -hematite, NaAlSi 3 O 8 -albite, CaSO 4 -anhydrite and an amorphous phase [Angjusheva, Fidancevska, & Jovanov, 2012].…”

“…There are few works that deal with the topic of production of ceramics from pure fl y ash [Pimraksa, et al] [Angjusheva, Fidancevska, & Jovanov, 2012]. The effect of particle size distribution, as a key process variable that controls sintering and the properties of the ceramics, was reported [Ilic, et al, 2003].…”

Resistance to frost action and microbiological corrosion of novel ceramic composites

“…This property, together with porosity of ceramics, is an important factor considering resistance to freezing temperatures. Bearing in mind this relationship, the idea of our work was to estimate the dominant deterioration mechanism regarding frost and biocorrosion actions of the novel ceramic composites, found as optimal in previous work [25], where a significant part of the clay material (40 wt. %) was replaced with fly ash.…”

“…Taking into account that there are numerous studies published concerning the benefits of fly ash utilization in the production of ceramic composites, and the fact that frost resistance and microbiological corrosion has not received the same attention, the aim of our work was to examine the durability of composites based on fly ash and clay materials. For that purpose, was used the novel ceramic composite composed of 60 wt.% clay and 40 wt.% fly ash sintered at 1100 oC/1h, which was found as optimal in our previous work [25] where fly ash content and the sintering temperature varied from 10 to 90 wt.% and from 900 to 1100 oC/1h, respectively. Bearing in mind all the mentioned facts, the experimental investigation presented in this work was performed by combining exploitation capacity (resistance to freezing cycles and microbiological corrosion) of the characteristics of the novel ceramic product i.e.…”

Production of Glass-Ceramics From Waste Materials and Optimization of the Main Process Parameters

“…% of the entire fly ash production is disposed off in landfills or ash ponds. The biggest quantity of the total generated fly ash has been utilized in the construction industry either as addition to concrete [3,4] or cement raw material [5,6], road construction [7], ceramics [8,9], mineral fillers [10], agriculture [11] etc. However the various reports indicate a growing interest for recycling and new applications.…”