Production of ceramics from coal fly ash

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 1100?C using the heating rate of 10?C/min.

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Effect of Bentonite on Properties of Fly Ash-Based Porous Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.412.195 ◽

2011 ◽

Vol 412 ◽

pp. 195-198 ◽

Cited By ~ 1

Author(s):

Xiao Rong Liu ◽

Lin Xiong ◽

Ai Ying Chen

Keyword(s):

Sustainable Development ◽

Fly Ash ◽

Liquid Phase ◽

Bending Strength ◽

Porous Ceramics ◽

Environmental Conservation ◽

Liquid Phase Sintering ◽

Bend Strength ◽

Sintering Process ◽

Coal Powder

Recycling fly ash in a way with high benifits is important to environmental conservation and sustainable development. Using bentonite as binder and coal powder as pore-forming agent, the fly ash-based porous ceramics was prepared and effects of bentonite on performances of the ceramics were researched. With the increasing of bentonite content from 3.0mass% to 5.0mass%, liquid phase sintering process was promoted and the bending strength improved from 5.46 to 6.09Mpa. Contrarily, the open porosity decreased from 48.18% to 44.39%. But more bentonite addition would result in some larger pores distributed inhomogeneously in the microstructure so that the bend strength fell down and porosity went up.

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Liquid phase sintering of dense and porous glass-ceramics from coal fly-ash and waste glass

Science of Sintering ◽

10.2298/sos0402087b ◽

2004 ◽

Vol 36 (2) ◽

pp. 87-92 ◽

Cited By ~ 7

Author(s):

J. Bossert ◽

E. Fidancevska ◽

B. Mangutova ◽

B. Panova ◽

D. Milosevski ◽

...

Keyword(s):

Fly Ash ◽

Polyurethane Foam ◽

Bending Strength ◽

Coal Fly Ash ◽

Glass Ceramics ◽

Liquid Phase Sintering ◽

Waste Glass ◽

Power Stations ◽

C Fibers ◽

Coal Power

Glass-ceramics were produced utilizing fly-ash from coal power stations and waste glass of TV monitors, windows and flask glass. The powder technology route was employed. The mixture of 50% fly ash and 50% waste TV glass increases the bending strength from 12?1 to 56?4 MPa and E-modulus from 6?1 to 26?3 GPa. Using polyurethane foam and C-fibers as pore creators porosity of 70?4 and 55?5 %, respectively, can be obtained-modulus and bending strength of the porous systems obtained by polyurethane foam and C-fibers was 2.7?0.5 GPa and 4.5?1 MPa and 7.1?1 GPa and 9.3?2 MPa respectively.

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Synthesis and Na+ Ion Conductivity of Stoichiometric Na3Zr2Si2PO12 by Liquid-Phase Sintering with NaPO3 Glass

Materials ◽

10.3390/ma14143790 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3790

Author(s):

Yongzheng Ji ◽

Tsuyoshi Honma ◽

Takayuki Komatsu

Keyword(s):

Solid State ◽

Liquid Phase ◽

Sintering Temperature ◽

Liquid Phase Sintering ◽

Ion Conductivity ◽

X Ray Diffraction ◽

Conventional Solid State Reaction ◽

X Ray ◽

Sintering Time ◽

Lower Activation

Sodium super ionic conductor (NASICON)-type Na3Zr2Si2PO12 (NZSP) with the advantages of the high ionic conductivity, stability and safety is one of the most famous solid-state electrolytes. NZSP, however, requires the high sintering temperature about 1200 °C and long sintering time in the conventional solid-state reaction (SSR) method. In this study, the liquid-phase sintering (LPS) method was applied to synthesize NZSP with the use of NaPO3 glass with a low glass transition temperature of 292 °C. The formation of NZSP was confirmed by X-ray diffraction analyses in the samples obtained by the LPS method for the mixture of Na2ZrSi2O7, ZrO2, and NaPO3 glass. The sample sintered at 1000 °C for 10 h exhibited a higher Na+ ion conductivity of 1.81 mS/cm at 100 °C and a lower activation energy of 0.18 eV compared with the samples prepared by the SSR method. It is proposed that a new LPE method is effective for the synthesis of NZSP and the NaPO3 glass has a great contribution to the Na+ diffusion at the grain boundaries.

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An Investigation of Usability of Brown Coal Fly Ash for Building Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.438-439.30 ◽

2013 ◽

Vol 438-439 ◽

pp. 30-35 ◽

Cited By ~ 2

Author(s):

Nirdosha Gamage ◽

Sujeeva Setunge ◽

Kasuni Liyanage

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Brown Coal ◽

Water Contamination ◽

Building Materials ◽

Coal Fly Ash ◽

Sustainable Building ◽

Laboratory Investigations ◽

Cold Pressed ◽

Initial Results

The Victoria State of Australia has the second largest reserves of brown coal on earth, representing approximately 20% of the worlds reserves, and at current use, could supply Victoria with its energy for over 500 years. Its combustion, annually, yields up to 1.3 million tonnes of fly ash, which is largely use for land-fills. Disposal of fly ash in open dumps cause massive environmental problems such as ground water contamination that may create various health problems. This study focuses on the usability of brown coal fly ash to develop a sustainable building material. A series of laboratory investigations was conducted using brown coal fly ash combined with cement and aggregate to prepare cold pressed samples aiming to test their properties. Initial results indicate that compressive strength satisfies minimum standard compressive strength required for bricks or mortar.

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The Effect of Substituting Rdf on the Physical and Environmental Properties of Coal Fly Ash

MRS Proceedings ◽

10.1557/proc-136-223 ◽

1988 ◽

Vol 136 ◽

Author(s):

Ashaari B. Mohamad ◽

David L. Gress

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Physical Properties ◽

Activity Index ◽

Coal Fly Ash ◽

Pozzolanic Activity ◽

Portland Cement Concrete ◽

Fly Ash Concrete ◽

Refuse Derived Fuel ◽

Cadmium And Lead

ABSTRACTRefuse-derived-fuel (RDF) consisting mainly of waste paper and plastics is a viable fuel source for the production of power. An experimental test burn partially substituting coal with RDF was undertaken by the Public Service of New Hampshire at the Merrimack Power Station.Five percent and ten percent RDF were substituted, on a BTU basis, for coal in the test bums. The chemical and physical properties of the resulting fly ash were determined. Twelve test burn days were run with 4 days of 5% RDF and 8 days of 10% RDF. Emphasis was placed on investigating the effect of the RDF fly ash on Portland cement concrete.Most of the chemical and physical properties of the coal-RDF fly ash were found to be comparable with ordinary coal fly ash except for the amount of cadmium and lead, the pozzolanic activity index and the compressive strength of fly ash concrete. Cadmium and lead were at average levels of 5.1 ppm and 102.6 ppm for the 5% RDF, and 7.8 ppm and 198.3 ppm for the 10% RDF, respectively. Although the pozzolanic activity index of coal-RDF fly ash increases over normal coal fly ash, preliminary results show that the 28-day compressive strength of concrete with direct replacement of cement and sand decreases by up to 30%. Leaching tests on crushed concrete were conducted to evaluate the environmental effect of acid rain.

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Utilization of Electroplating Sludge as Subgrade Backfill Materials: Mechanical and Environmental Risk Evaluation

Advances in Civil Engineering ◽

10.1155/2018/4891418 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Yu Zhang ◽

Peixin Shi ◽

Lijuan Chen ◽

Qiang Tang

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Water Content ◽

Environmental Risk ◽

Coal Fly Ash ◽

Surrounding Environment ◽

Electroplating Sludge ◽

Backfill Materials ◽

Standard Limit ◽

The Impact

The electroplating sludge may pose serious threat to human health and surrounding environment without safe treatment. This paper investigated the feasibility of using electroplating sludge as subgrade backfill materials, by evaluating the mechanical properties and environmental risk of the cement-coal fly ash solidified sludge. In this study, Portland cement and coal fly ash are used to solidify/stabilize the sludge. After curing for 7, 14, and 28 days, the stabilization/solidification sludge specimens were subject to a series of mechanical, leaching, and microcosmic tests. It was found that the compressive strength increased with the increase of cement content, curing time, and the cement replacement by coal fly ash besides water content. Among these factors, the impact of water content on the compressive strength is most noticeable. It was observed that the compressive strength declined by 87.1% when the water content increased from 0% to 10%. Besides, leaching tests showed that the amount of leaching heavy metals were under the standard limit. These results demonstrated utilization of electroplating sludge in subgrade backfill material may provide an alternative for the treatment of electroplating sludge.

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