Aluminum Ash Research Articles

Pretreatment of municipal solid waste incineration fly ash and preparation of solid waste source sulphoaluminate cementitious material

Municipal solid waste incineration fly ash (MSWI-FA) is a kind of hazardous waste, and it is of great significance to treat it harmlessly and resourcefully. This study proposes the preparation of sulphoaluminate cementitious materials using water-washed MSWI-FA, flue-gas desulfurization gypsum, and aluminum ash. The changes in the composition and morphology of MSWI-FA before and after washing were investigated, and the effects of various washing conditions on the removal rate of chloride salt from MSWI-FA were analyzed. The effect of firing temperature on the mineral content of the sulphoaluminate cementitious material was also investigated. In addition, the strength and heavy metal leaching characteristics of the corresponding materials were tested. The results show that more than 90% of chloride salts were removed by water washing MSWI-FA two times. Using MSWI-FA as the main raw material, the sulphoaluminate cementitious material containing mostly calcium sulphoaluminate and dicalcium silicate could be prepared successfully at 1270 °C; the amount of MSWI-FA in the raw material can be as high as 35% (dry weight). Moreover, the sulphoaluminate cementitious material can effectively solidify heavy metals in the raw materials. The leaching concentrations of eight heavy metal ions, i.e., Cu, Zn, Cd, Pb, Cr, Ni, Ba, and As are far lower than the concentration limits set by national standards.

Regression modelling on wear behaviour of nano fly ash–aluminium alloy matrix composites

The demand for particle-reinforced composites has been increasing progressively. Hence, there is an exigency to use low-cost particles or solid waste particles as a reinforcement phase in order to reduce the cost of the composite. Fly ash is a solid waste consisting of various oxides such as silicon dioxide (SiO2), aluminium oxide (Al2O3) and iron (III) oxide (Fe2O3), which will contribute to improving wear resistance. Hence, an attempt is made to use nanostructured fly ash as particle reinforcement to produce high-wear-resistance composite materials. Microsized fly ash was converted to nanostructured material by high-energy ball milling, and the crystallite size was reduced to 27 nm after 30 h of milling. The influence of applied load, sliding speed, sliding time and fly ash reinforcement on dry sliding wear of the metal matrix composites is determined. Wear resistance was increased with increase in fly ash fraction, and beyond 10 wt%, it was decreased. The increased frictional thrust at higher load results in increased debonding and wear rate. The regression model was developed by using the statistical software Minitab R17.1.0 to predict the wear behaviour of the composites under conditions of different normal loads and time periods. The model has been validated, and a good agreement was observed.

Experimental Investigation of Al-Mg-SiC-Fly Ash Composites for Automotive Alloy Wheel Rims

The conservation of resources is the biggest concern for the past half century. The mankind is heading towards the betterment of living with a key intention to obtain pertaining results with less effort. One such field which has been an extensive outreach for research and innovation is the composite materials. This study focuses on design and development of a new composition of materials which has enhanced mechanical properties than the existing materials. This study is about combining four materials namely aluminium, magnesium, SiC and fly ash in various proportions and to test the obtained specimens. The test specimens are fabricated with aluminium as the metal matrix and other materials (Mg, SiC and fly ash) as reinforcements. Three different combinations are designed by keeping the fly ash, silicon carbide at constant percentage and varying the contents of aluminium and magnesium. The results of the tests are promising and the proposed composition can be a potential reliable replacement material for existing alloy wheels.

Performance of New Non-Clinker Aluminum Dross Cement Curing Agent

The growth of China's aluminum industry makes more and more waste aluminum dross, although there are some ways for recycling aluminum dross, but still cannot absorb its output. This paper attempts to develop an effective concrete curing agent with high content of aluminum ash so as to effectively solve the problems of waste residue accumulation. The properties of a new aluminum dross cement-curing agent based on industrial solid wastes combined with an activator are evaluated through orthogonal testing using standard testing methods for compressive strength, bending strength, setting time, soundness, and the water requirement of standard consistency. The influence of the curing conditions and the water to cement ratio on the strength obtained with the aluminum dross curing agent was also studied along with the durability to water erosion, resistance to sulfate attack and stability when subjected to dry/wet cycles or high temperature. The results obtained demonstrate that this new clinker-free aluminum ash curing agent provides good mechanical properties and a high resistance to water and sulfate attack. This material was also found to be suitable for use as a curing agent in soil solidification.

Preparation of Alumina from Aluminum Ash by Sintering with Sodium hydroxide

Aluminum ash is an industrial waste residue produced during alumina electrolysis and aluminum processing and casting. In the experiment, alumina powder with a purity of 98.97% was prepared by sintering with sodium hydroxide and the process conditions affecting the dissolution rate of Al2O3 from aluminum ash were studied. The best process conditions for the dissolution of Al2O3 are the sintering temperature of 700°C, the alkali-ash ratio of 1.2:1, and the time of 2h using orthogonal experiments. The phases of the aluminum ash and alumina were determined by X-ray diffraction(XRD) analysis. The chemical compositions of the aluminum ash and alumina were determined by X-ray fluorescence (XRF) spectroscopy. The microstructure and morphology of the aluminum ash and alumina were studied with scanning electron microscopy (SEM). Alumina prepared can be used as a metallurgical material.

The study on determination of Fluoride in Aluminum Ash Leachate

The content of fluoride ion in aluminum ash leaching solution was measured by using the ion selective electrode method accurately. The measure conditions were also studied. Theoretical and experimental results show that pH, temperature, instrument performance and coexisting ions have an important influence on the measure of fluoride ions in aluminum ash leaching solution. Hydrochloric acid was added to adjust pH closing to the neutral and adding 10 mL total ionic strength adjustment buffer solution, Controlling the pH between 5-6. The temperature was consistent with the standard solution, and the measurement result was the most accurate. The fluoride ion content in the aluminum ash leaching solution reaches 446mg/L, far exceeding the national standard.

Viscosity Property and Melt Structure of CaO–MgO–SiO<sub>2</sub>–Al<sub>2</sub>O<sub>3</sub>–FeO Slag System

For the purpose to describe the change of the viscosity properties of the converter slag during smelting reduction process using aluminum ash as reductant and provide basis for technology development, the viscosity of CaO–MgO–SiO2–Al2O3–FeO slag system at a fixed basicity of 3 was measured with the various ratio of A/(A+F) (w(Al2O3)/w(Al2O3+FeO)) by the cylinder method, and the structural of the melt was analyzed based on the FTIR and Raman spectroscopy to further explain the evolution behavior of viscosity. The results showed that viscosity of the slag was increased with increasing the ratio of A/(A+F). When this ratio increased from 0.17 to 0.5, the simple network units of the molten slag were polymerized into more complex network structure, resulting in a slow increase in viscosity from 0.65 dPa·s to 0.91 dPa·s at 1873 K. With further increasing this ratio to 1.0, the main structure was converted from silicate structure to aluminate structure. In addition, the polymerization degrees of aluminate units and silicate units both increased, which eventually led to an rapid increase in the viscosity from 0.91 dPa·s to 1.94 dPa·s.

Association between Duration Working with Lung Disruption Condition using Pulmonary Vital Capacity (PVC) Test on Lathe Worker at Yogyakarta, Indonesia

Background: For the past decade, pulmonary fibrosis occurred due to excessive connective tissue in the lung caused by inflammation. Inhaled aluminum constantly has been thought as a key factor for pulmonary fibrosis for workers. Within the next few years, aluminum ash would become toxic inside the body and cause a hardening or fibrosis of the lungs. The present paper aims to analyze association between duration working with lung disruption condition on lathe workers in Z industry, Yogyakarta. Method: The research used a cross-sectional design. The sample was 16 lathe workers at Z Industry, Yogyakarta. Independent variable were age, period employment, and duration of work. The dependent variable was lung disruption. Measurement of lung disruption used pulmonary vital capacity test. Data analysis was using chi-square test and Risk Prevalence (PR). Result: Age and the period of employment had a quite weak association with lung disruption (p=0,158;0,279). While the duration of work has a strong association with lung disruption (p=0,729). Conclusion: Duration of work has a strong association with lung disruption. This is caused by a worker which inhaled aluminum dust continuously, aluminum dust would be accumulated, becomes toxic and caused parenchyma tissues damaged in the lung. © 2019, Indian Journal of Forensic Medicine and Toxicology. All rights reserved.

Microstructure, Hardness and Tensile Properties of Friction Stir Welded Aluminum Matrix Composite Reinforced with SiC and Fly Ash

In the present work, aluminum alloy 6061/SiC/fly ash aluminum matrix composites were welded successfully using friction stir welding process. Microstructure of weld joints was examined using optical microscope and scanning electron microscope. Mechanical properties namely, microhardness and ultimate tensile strength of the joints were studied. The results were correlated to microstructural changes caused by friction stir welding process. Microstructure in the stirred zone exhibits the uniform distribution of SiC and fly ash particles. Especially fine grains were formed on the advancing side than on the retreating side, due to the different variation between tool direction and welding direction. Higher hardness value is observed on the advancing side (132 Hv) than on the retreating side (124 Hv). Transverse tensile test of weld sample exhibits higher joint efficiency of 85.06% with respect to ultimate tensile strength. Fracture study reveals ductile mode of failure. Weld joints got fractured in heat affected zone on the retreating side, which indicates the weakest part of the weld joint. Based on thermodynamic analysis, the optimum heat input was found to be 756 J mm−1, resulting in higher strength of weld joints due to uniform distribution of reinforcement particles in the nugget zone.

Selective synthesis of zeolites A and X from two industrial wastes: Crushed stone powder and aluminum ash

Crushed stone powder and aluminum ash are industrial wastes, and effective utilization of these wastes has been highly expected. Since the main components of the two wastes are Si, Al and O, those wastes can be used as starting materials for synthesis of zeolites of which some types have been commercialized as catalysts and ion-exchangers. In this study, zeolites A and X well-known as practical materials were successfully synthesized with high purity using the two industrial wastes by a mild process based on two hydrothermal treatments with intermediate acid treatment. In the first hydrothermal treatment at 150 °C, quartz in the crushed stone powder was dissolved and acid-soluble hydroxysodalite (Na8(AlSiO4)6(H2O)2(OH)2) with Si/Al = 1 and sodium aluminosilicate (Na6(AlSiO4)6) were formed. Those compounds were dissolved with HCl aq. solution. The zeolites were successfully synthesized from the second hydrothermal treatment of the yellow dried filtrates at 80 °C in NaOH aq. solution. In the process proposed, removal of Ca from the crushed stone powder was effective to formation of zeolites A and/or X. Selective synthesis of zeolites A and X was achieved by controlling the acid treatment conditions. Furthermore, the effect of the drying condition of the filtrate obtained after the acid treatment was also investigated on the differences in the product phase.

Comparison of leaching behaviors of aluminum in ash from combustion and catalytic gasification

The leaching behaviors of aluminum in ash from combustion and catalytic gasification, and effects of Na2CO3 addition (0–15%), temperature (600–1000°C) on Al leaching behaviors and mineral composition were investigated. The compositions of ash from combustion and gasification, and acid leaching residue were investigated by XRD. The results show that the combustion ash is predominantly composed of mullite, while that from catalytic gasification is sodium aluminum silicate ((Na2O)0.33NaAlSiO4). The Al extraction yield of combustion ash only reaches 40% at leaching conditions of 6 mol/L H2SO4, 60°C and 30 min, while that of catalytic gasification ash with 10% Na2CO3 addition can reach 88%. The catalytic gasification with Na2CO3 addition can achieve higher Al extraction yield.

High temperature sliding wear behavior of AA6061/fly ash aluminum matrix composites prepared using compocasting process

Fly ash particle reinforced aluminum matrix composite (AMCs) has been fabricated using a stir casting furnace by employing compocasting technique. The presence of fly ash particles in the compocast fabricated AMCs has been tested by X-ray diffraction and scanning electron microscopy (SEM). The wear behaviour of compocast fabricated AMCs and matrix alloy AA6061were tested using Pin-On-Disc apparatus. The effect of fly ash particulate content (0, 4, 8 and 12 wt.%) and temperature (40, 80, 120, 160, 200 and 240 °C) on wear rate and worn surface of the AMCs were studied. The reinforcement of hard fly ash particles is successful to improve the wear resistance of the compocast AMCs at all temperatures studied in this work. SEM micrograph of worm surface indicated that at elevated temperature the prime wear process for the AA6061 alloys were adhesion and metal flow, whereas for AA6061/Fly ash compocast composite adhesion, metal flow and oxidation are the most influencing wear process.

Preparation, Characterization and Properties of New Low Cost Multi-Channel Ceramic Membrane Tube for Water Treatment

Multi-channel tubular macroporous ceramic membrane supports were successfully prepared via a plastic extrusion method, using α-Al2O3 with a purity of 94wt% and aluminum hydroxide as starting materials, the ash of burned rice hull as the pore-forming agent and a small amount of talc and kaolin as sintering aids. The effects of the kinds of sintering aids, content of aluminum hydroxide and ash of burned rice hull on the porosity, pore size and distribution, compressive strength, acid and alkali corrosion resistance and permeability of the new multi-channel ceramic membrane supports were investigated. The results showed that aluminum hydroxide effectively improved the mechanical strength, and the support sintered at 1450°C for 4h with the aluminum hydroxide content of 20wt% exhibited higher performance: average pore size diameter and porosity were nearly 5μm and 50% respectively, the compressive strength was around 7MPa, the pure water flux was 26m3/m2h at 0.1MPa and changed to nearly 20m3/m2h after the acid and alkali treatment at 90°C for 48h. The support possesses excellent corrosion resistance and can be used in the water treatment process with large range of pH value.

An experimental analysis of coal aluminium mixture in coal fired furnace

Coal is an important fuel used in boiler furnaces. There are problems like unburnt coal and solid wastes like ash contain arsenic, selenium, chromium and cadmium while using it. In order to avoid all such difficulties, aluminium metal powder in various grain sizes mixed with pulverized coal and burned. aluminium metal powder is one of the pyrotechnics having higher calorific value and low ignition temperature. The thermal behavior of aluminium powder along with coal is recorded in DTA. The collected ashes were tested in Scanning Electron Microscope and X-Ray Diffraction meter. The SEM results show that coal ash is having granular and regular structure. All the particles have a size range from 5 to 8 μm. On the other hand, the aluminium coal mixture ash shows a fibrous matrix and the particles are irregular. In XRD graph, the peaks in the graph show orientation of atoms in particular plane and angle. The coal ash has a lot of peaks, but the maximum count value reaches only to 340.97. However the value of counts reaches a maximum of 1,539.06 for aluminium ash. This denotes high atom orientation in a single lattice plane.

Development, characterization and erosion wear response of plasma sprayed fly ash–aluminum coatings

This paper describes the processing, characterization and the erosion wear response of a new class of metal–ceramic composite coatings deposited on metal substrates by plasma spraying. Coatings are developed on aluminum substrates using fly ash pre-mixed with aluminum powder in different weight proportions at various plasma torch power levels ranging from 9 to 18 kW DC. The coatings are characterized in terms of thickness, interface adhesion strength and deposition efficiency. Maximum adhesion strength of about 35 MPa is recorded with coatings deposited at 12 kW power level. It is noticed that the adhesion strength of fly ash coating is improved with pre-mixing of aluminum up to 15 wt.% in the feed material. To study the erosion wear behavior of the coatings, a plan of experiments based on the Taguchi technique is used to acquire the erosion test data in a controlled way. An orthogonal array and signal-to-noise ratio are employed to investigate the influence of the impingement angle, impact velocity, erodent size, stand-off-distance and the aluminum content in the feed stock on the erosion rate. The study reveals that the impact velocity is the most significant factor influencing the erosion wear rate of these coatings.

Compaction of fly ash–aluminum alloy composites and evaluation of their mechanical and acoustic properties

The density and elastic moduli of green compacts can be determined by ultrasonic method with the help of pre-prepared diagrams. In this way, pressing conditions can be taken under control easily. In this study, fly ash particles were used as fillers in an aluminum alloy matrix material. The weight fractions of fly ash in the composites were in the range of 5–30%. The resulting composites were compacted at pressures ranging from 63 MPa to 316 MPa. It was observed that the green density increased with increasing compacting pressure and decreased with increasing weight percent of fly ash particles resulting in lightweight composites. The green compact composites were also tested using an ultrasonic non-destructive evaluation method. Results showed that ultrasonic velocities are a strong function of the density and the fly ash fraction in this material and could be potentially used to predict the density and the fly ash fraction as well as the elastic moduli of the metal matrix composite.

Optical and Chemical Methods of Metal Ash Analysis and Tin Recovery

'Metal ash' presents a waste disposal problem in most of the developing countries as the industries employ obsolete technologies. In this paper we describe analysis of tin ash, zinc ash and aluminium ash by means of optical methods, such as X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), electron probe micro analysis (EPMA), scanning electron microscopy (SEM) and chemical methods. The results of tin ash obtained by XRD method matched well with the cassiterite, a naturally occurring mineral of tin. ICP-MS studies reveal the presence of a large number of tracer metals, which may cause pollution by tertiary dispersion and this aspect is discussed. Conversely, the data generated by chemical methods are limited. However, the methods are simple and cost-effective. Then, they can easily be adopted by low-budget industries. Simple and cost-effective process to recover tin from tin ash is described. It is based on heating tin ash with sodium cyanide to about 900 degrees C to separate tin component from the metal ash. The process recovers good quality tin and offers a very high yield. The process can be scaled up to small pilot plant.

Carbochlorination of Aluminum from Non-Bauxite Sources

There has been increased interest in the United States in developing the technology to recover aluminum from non-bauxite sources stemming from a need to develop domestic aluminum sources.1, 2 Several domestic sources of aluminum have been defined by the U.S. Bureau of Mines;3 the types and approximate tonnages of these are listed in Table I. Patterson and Dyni4 of the U.S. Geological Survey identified several additional non-bauxite sources of aluminum, including alunite (37% Al2O3), dawsonite (35% Al2O3), and coal ash (8–40% Al2O3). The U.S. Bureau of Mines has indicated that the future aluminum resources consist mainly of anorthosites, and has listed research on the recovery of alumina from kaolin, anorthite, and dawsonite as a major objective.5 It is also interesting to note that there has been a discussion of the importance of finding a method for processing lunar anorthite to produce construction materials for space.6

High-temperature chlorination of coal ash in a fluidized bed. 1. Recovery of aluminum

The high-temperature chlorination of the aluminium fraction in Alberta coal ash was investigated experimentally using a gas-fluidized bed reactor. With carbon (fluid coke) and carbon monoxide present as reducing agents, about 25% of aluminium in ash could be chlorinated in 2 h at temperatures above 900 C. By using standard statistical technique, it was discovered that the chlorination of aluminium above 900 C was unaffected by a variation in temperature. On the other hand, reducing the particle size and increasing the Cl/sub 2//CO ratio did have beneficial effects. Global reaction rate data indicate two very distinct reaction regions. In the first 10 min a high chlorination rate was observed (i.e., about 9 g of aluminium chlorinated/kg of initial Al-min). This was followed by a second region (10-120 min) where the global rate was reduced by a factor of about 7 and reached a constant value. Reasons for the changing reaction conditions are also discussed.

A STUDY OF PODZOLIZATION

Journal of Soil ScienceVolume 5, Issue 1 p. 50-56 A STUDY OF PODZOLIZATION V. THE MOBILIZATION OF IRON AND ALUMINIUM BY ASPEN AND ASH LEAVES C. BLOOMFIELD, C. BLOOMFIELD Rothamsted Experimental Station, HarpendenSearch for more papers by this author C. BLOOMFIELD, C. BLOOMFIELD Rothamsted Experimental Station, HarpendenSearch for more papers by this author First published: January 1954 https://doi.org/10.1111/j.1365-2389.1954.tb02175.xCitations: 16AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume5, Issue1January 1954Pages 50-56 RelatedInformation