Potential Applications of Vitrified Slag as a Product of Plasma Arc Melting

The present article presents the potential of vitrified slag, one of the products of plasma arc melting, for further industrial applications based on previous experiments. The existing publications on the investigation into this field is hence supplemented with our series of experiments conducted using vitrified slag from plasma arc gasification and melting of fly ash from municipal waste, as well as a mixture consisting of fly ash produced by fluidised-bed boilers in a heat power plant and recovered asbestos cement roofing sheets. It should be noted that the process of plasma arc gasification and melting facilitates not only a significant reduction of the quantity of processed hazardous wastes, but also a possibility of transforming such wastes into an inert product, which may be used as an input raw material in certain industrial processes.

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Recovery of Cenospheres and Fine Fraction from Coal Fly Ash by a Novel Dry Separation Method

Energies ◽

10.3390/en13143576 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3576

Author(s):

Jan Wrona ◽

Witold Żukowski ◽

Dariusz Bradło ◽

Piotr Czupryński

Keyword(s):

Fly Ash ◽

Coal Fly Ash ◽

Fine Fraction ◽

Free Fall ◽

Raw Material ◽

Fluidised Bed ◽

Air Chamber ◽

Pneumatic Separation ◽

Bed Separation ◽

Separation Product

Aluminosilicate microspheres are a valuable fraction of coal fly ash with diverse applications due to their low density. Currently, there is no efficient and ecologically rational method of cenosphere recovery from fly ash. A combination of dry methods for the recovery of both fine ash particles and aluminosilicate microspheres from coal fly ash is presented. It is comprised of fluidised bed separation followed by screening and pneumatic separation in a free-fall air chamber. Fluidised bed separation was assisted by a mechanical activator to prevent agglomeration. This step reduced the portion of material that required further treatment by 52–55 wt.%, with the recovery of microspheres exceeding 97%. Then, the concentrates were individually subjected to pneumatic separation. The final separation product for the fly ash containing 0.64 wt.% cenospheres was a cenosphere concentrate that constituted about 17 wt.% of the initial fly ash. The recovery of cenospheres was around 81%. Usage of a combination of dry methods allowed for maintaining almost 83 wt.% of the raw material in its dry form. Furthermore, the produced fly ash grain fractions could be used for different industrial purposes.

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FLY ASH FROM THERMAL POWER PLANT, RAW MATERIAL FOR GLASS-CERAMIC

Environmental Engineering and Management Journal ◽

10.30638/eemj.2013.041 ◽

2013 ◽

Vol 12 (2) ◽

pp. 337-342 ◽

Cited By ~ 1

Author(s):

Firuta Goga ◽

Roxana Dudric ◽

Calin Cormos ◽

Florica Imre ◽

Liliana Bizo ◽

...

Keyword(s):

Fly Ash ◽

Power Plant ◽

Glass Ceramic ◽

Thermal Power Plant ◽

Thermal Power ◽

Raw Material ◽

Plant Raw Material

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Study of the Physical Behavior of a New Composite Material Based on Fly Ash from the Combustion of Coal in an Ultra-Supercritical Thermal Power Plant

Journal of Composites Science ◽

10.3390/jcs5060151 ◽

2021 ◽

Vol 5 (6) ◽

pp. 151

Author(s):

Mustapha El Kanzaoui ◽

Chouaib Ennawaoui ◽

Saleh Eladaoui ◽

Abdelowahed Hajjaji ◽

Abdellah Guenbour ◽

...

Keyword(s):

Composite Material ◽

Fly Ash ◽

Power Plant ◽

High Performance ◽

Thermal Power ◽

Recovery Process ◽

Industrial Wastes ◽

Raw Material ◽

Polymerization Reaction ◽

High Performance Composite

Given the amount of industrial waste produced and collected in the world today, a recycling and recovery process is needed. The study carried out on this subject focuses on the valorization of one of these industrial wastes, namely the fly ash produced by an ultra-supercritical coal power plant. This paper describes the use and recovery of fly ash as a high percentage reinforcement for the development of a new high-performance composite material for use in various fields. The raw material, fly ash, comes from the staged combustion of coal, which occurs in the furnace of an ultra-supercritical boiler of a coal-fired power plant. Mechanical compression, thermal conductivity, and erosion tests are used to study the mechanical, thermal, and erosion behavior of this new composite material. The mineralogical and textural analyses of samples were characterized using Scanning Electron Microscopy (SEM). SEM confirmed the formation of a new composite by a polymerization reaction. The results obtained are very remarkable, with a high Young’s modulus and a criterion of insulation, which approves the presence of a potential to be exploited in the different fields of materials. In conclusion, the composite material presented in this study has great potential for building material and could represent interesting candidates for the smart city.

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Fly ash as a raw material for low-carbon cement clinkers and its radiological properties

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/s10967-021-07719-7 ◽

2021 ◽

Author(s):

Miljana Mirković ◽

Ljiljana Kljajević ◽

Snežana Nenadović ◽

Sabina Dolenec ◽

Katarina Šter ◽

...

Keyword(s):

Fly Ash ◽

Raw Material ◽

Low Carbon ◽

Cement Clinkers ◽

Radiological Properties

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Hydrothermal Synthesis of Sodalite-Type N-A-S-H from Fly Ash to Remove Ammonium and Phosphorus from Water

Materials ◽

10.3390/ma14112741 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2741

Author(s):

Pengcheng Lv ◽

Ruihong Meng ◽

Zhongyang Mao ◽

Min Deng

Keyword(s):

Fly Ash ◽

Adsorption Capacity ◽

Removal Rate ◽

Kinetic Studies ◽

Solute Concentration ◽

Raw Material ◽

Sodium Aluminosilicate ◽

Equilibrium Data ◽

One Step ◽

Ft Ir

In this study, the hydrated sodium aluminosilicate material was synthesized by one-step hydrothermal alkaline desilication using fly ash (FA) as raw material. The synthesized materials were characterized by XRD, XRF, FT-IR and SEM. The characterization results showed that the alkali-soluble desilication successfully had synthesized the sodium aluminosilicate crystalline (N-A-S-H) phase of sodalite-type (SOD), and the modified material had good ionic affinity and adsorption capacity. In order to figure out the suitability of SOD as an adsorbent for the removal of ammonium and phosphorus from wastewater, the effects of material dosing, contact time, ambient pH and initial solute concentration on the simultaneous removal of ammonium and phosphorus are investigated by intermittent adsorption tests. Under the optimal adsorption conditions, the removal rate of ammonium was 73.3%, the removal rate of phosphate was 85.8% and the unit adsorption capacity reached 9.15 mg/L and 2.14 mg/L, respectively. Adsorption kinetic studies showed that the adsorption of ammonium and phosphorus by SOD was consistent with a quasi-secondary kinetic model. The adsorption isotherm analysis showed that the equilibrium data were in good agreement with the Langmuir and Freundlich model. According to thermodynamic calculations, the adsorption of ammonium and phosphorus was found to be a heat-absorbing and spontaneous process. Therefore, the preparation of SOD by modified FA has good adsorption properties as adsorbent and has excellent potential for application in the removal of contaminants from wastewater.

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Coal Fly Ash Derived Silica Nanomaterial for MMMs—Application in CO2/CH4 Separation

Membranes ◽

10.3390/membranes11020078 ◽

2021 ◽

Vol 11 (2) ◽

pp. 78

Author(s):

Marius Gheorghe Miricioiu ◽

Violeta-Carolina Niculescu ◽

Constantin Filote ◽

Maria Simona Raboaca ◽

Gheorghe Nechifor

Keyword(s):

Fly Ash ◽

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Coal Fly Ash ◽

High Surface ◽

Industrial Applications ◽

Mixed Matrix Membranes ◽

Co2 Removal ◽

Mcm 41

In order to obtained high selective membrane for industrial applications (such as natural gas purification), mixed matrix membranes (MMMs) were developed based on polysulfone as matrix and MCM-41-type silica material (obtained from coal fly ash) as filler. As a consequence, various quantities of filler were used to determine the membranes efficiency on CO2/CH4 separation. The coal fly ash derived silica nanomaterial and the membranes were characterized in terms of thermal stability, homogeneity, and pore size distribution. There were observed similar properties of the obtained nanomaterial with a typical MCM-41 (obtained from commercial silicates), such as high surface area and pore size distribution. The permeability tests highlighted that the synthesized membranes can be applicable for CO2 removal from CH4, due to unnoticeable differences between real and ideal selectivity. Additionally, the membranes showed high resistance to CO2 plasticization, due to permeability decrease even at high feed pressure, up to 16 bar.

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Wire Arc Additive Manufacturing: Review on Recent Findings and Challenges in Industrial Applications and Materials Characterization

Metals ◽

10.3390/met11060939 ◽

2021 ◽

Vol 11 (6) ◽

pp. 939

Author(s):

Mukti Chaturvedi ◽

Elena Scutelnicu ◽

Carmen Catalina Rusu ◽

Luigi Renato Mistodie ◽

Danut Mihailescu ◽

...

Keyword(s):

Additive Manufacturing ◽

Structural Integrity ◽

Industrial Applications ◽

Raw Material ◽

Continuous Increase ◽

Control Optimization ◽

Modern Manufacturing ◽

Directed Energy ◽

Manufacturing Technologies ◽

Wire Arc Additive Manufacturing

Wire arc additive manufacturing (WAAM) is a fusion manufacturing process in which the heat energy of an electric arc is employed for melting the electrodes and depositing material layers for wall formation or for simultaneously cladding two materials in order to form a composite structure. This directed energy deposition-arc (DED-arc) method is advantageous and efficient as it produces large parts with structural integrity due to the high deposition rates, reduced wastage of raw material, and low consumption of energy in comparison with the conventional joining processes and other additive manufacturing technologies. These features have resulted in a constant and continuous increase in interest in this modern manufacturing technique which demands further studies to promote new industrial applications. The high demand for WAAM in aerospace, automobile, nuclear, moulds, and dies industries demonstrates compatibility and reflects comprehensiveness. This paper presents a comprehensive review on the evolution, development, and state of the art of WAAM for non-ferrous materials. Key research observations and inferences from the literature reports regarding the WAAM applications, methods employed, process parameter control, optimization and process limitations, as well as mechanical and metallurgical behavior of materials have been analyzed and synthetically discussed in this paper. Information concerning constraints and enhancements of the wire arc additive manufacturing processes to be considered in terms of wider industrial applicability is also presented in the last part of this paper.

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