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- Fly ash (4)
- Combustion; conversion; mineral matter; quantitative analysis; X-ray diffraction; X-ray fluorescence (2)
- 23-factorial design; manufactured coal ash aggregates; restoration; water quality (1)
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- Alite; calcium sulfoaluminate; ferrite; hybrid cements; industrial by-products (1)
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- Backfill; CLSM; compressive strength; mix design; flowable fill; fly ash (1)
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- Cetyl trimethyl ammonium bromide (1)
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- Coal ash; alite; calcium sulfoaluminate; X-Ray diffraction; Rietveld analyses; hybrid cement (1)
- Coal ash; coal combustion product; direct shear; shear strength; triaxial; vane shear (1)
- Coal by-products; FGD-gypsum; fly ash; wheat; nitrogen; fertilizer (1)
- Coal combustion by-products; brines; desulphurisation; FGD; hydration (1)
- Coal combustion by-products; coal ash; geopolymer concrete; cementless concrete; CO2 emissions (1)
- Coal combustion products (CCPs); coal ash; flue gas desulfurization (FGD); mercury; beneficial use; wallboard (1)
- Coal combustion products; fly ash; intelligent compaction; cost; quality assurance (1)
- Coal fly ash (1)
- Coal fly ash; Geopolymerization; Heavy metals; Leachability; Stabilization/solidification; Carbonation (1)
- Coal fly ash; bioassay; Vibrio fischeri; bioluminescence intensity; thermoelectric power plant (1)
- Coal fly ash; heavy metals; environmental impact; degree of contamination; pollution load index; bioaccumulation factor (1)
- Coal fly ash; mineral phases; sequential extraction procedure; chemical index of weathering; chemical index of alteration; pore water pH (1)
- Coal fly ash; poultry litter; bioenergy feedstock; eastern gamagrass; soil acidity; root system architecture (1)
Articles 61 - 85 of 85
Full-Text Articles in Bioresource and Agricultural Engineering
Effect Of Additive On The Performance Characteristics Of Centrifugal And Progressive Cavity Slurry Pumps With High Concentration Fly Ash Slurries, Sunil Chandel, S.N. Singh, V. Seshadri
Effect Of Additive On The Performance Characteristics Of Centrifugal And Progressive Cavity Slurry Pumps With High Concentration Fly Ash Slurries, Sunil Chandel, S.N. Singh, V. Seshadri
Coal Combustion and Gasification Products Journal Archive
Slurry pumps that are used in the hydraulic transportation of fly ash slurries through pipes in thermal power plants can be broadly classified into two main categories namely positive displacement and centrifugal pumps. The two types of pumps differ considerably in construction as well as in operating principle compared to the conventional pumps. The present study reports the effect of additive on the performance characteristics of centrifugal and progressive cavity screw pumps with fly ash slurries at high concentrations (above Cw < 50% by weight). Mixture of sodium carbonate and Henko detergent (5:1) at a concentration of 0.2% by weight has been used as an additive. For each type of pump, the effect of additive on the performance characteristics has been experimentally evaluated at rated speed with fly ash slurries in the concentration range of 50 to 70% by weight. The pump total head, overall efficiency and pump input power as a function of flow rate have been measured. The results obtained from the centrifugal slurry pump performance show that at rated speed, the performance of the pump improves with the addition of drag reducing additive. In the case of progressive cavity screw pump, pump performance characteristics and behavior were completely different as compared to the centrifugal slurry pump. At rated speed, the performance of screw pump deteriorates with the addition of drag reducing soap solution.
Zinc Speciation In Power Plant Burning Mixtures Of Coal And Tires, Luis F.O. Silva, Marcos L.S. Oliveira, Carmen Serra, James C. Hower
Zinc Speciation In Power Plant Burning Mixtures Of Coal And Tires, Luis F.O. Silva, Marcos L.S. Oliveira, Carmen Serra, James C. Hower
Coal Combustion and Gasification Products Journal Archive
Fly ash from the cyclone-boiler co-combustion of high-S, high volatile bituminous coal and tire-derived fuel (tdf) was studied using a variety of chemical, optical, and microbeam techniques. Fly ash, dominated by Al-Si glass with lesser amounts of coalderived carbons, Fe-spinels, and tire-derived carbons, has Zn concentrations ranging from 2200 ppm (1st ESP row) to 6900 ppm Zn (3rd ESP row). Zinc occurs in Zn-rich nanoparticles in the Al-Si glass phases and as ZnO in amorphous and crystalline nanominerals, Fe- and Zn-sulfides, Pb-Al-Fe sulfates, and Zn sulfates. Iron-rich, Al- and Ti-bearing spinels contain accessory Zn2+,Cr3+,Mn2+, and Pb2+. Fe-sulfates and phosphates nanoparticles …
Co-Disposal Of Dry Fgd By-Product With Coal Gasification Ash And Inorganic Brines, Jabulani S. Mahlaba, P.C. Pretorius, Subal Maharajh, M.P. Augustyn
Co-Disposal Of Dry Fgd By-Product With Coal Gasification Ash And Inorganic Brines, Jabulani S. Mahlaba, P.C. Pretorius, Subal Maharajh, M.P. Augustyn
Coal Combustion and Gasification Products Journal Archive
There is a growing pressure from the environmental authorities and public bodies to reduce anthropogenic pollution. Stringent environmental legislation is being implemented for industries around the world, even more so for coal consuming industries. Control of gaseous emissions is one of the areas that are receiving considerable attention towards sustainable development. Coal combustion in coal-fired power utilities emits SO~x~ to the atmosphere. Dry flue gas desulphurisation (FGD) is a well known technology often used to mitigate sulphur emissions in coal-fired power utilities. It traditionally uses lime to neutralise SO~x~, and forms a mixture of anhydrite (CaSO~4~), and calcium sulphite (CaSO~3~). …
A Multi-Analytical Approach To Understand The Chemistry Of Fe-Minerals In Feed Coals And Ashes, Marcos L.S. Oliveira, Frans Waanders, Luis F.O. Silva, Andre Jasper, Carlos H. Sampaio, Dursman Mchabe, Rachel S. Hatch, James C. Hower
A Multi-Analytical Approach To Understand The Chemistry Of Fe-Minerals In Feed Coals And Ashes, Marcos L.S. Oliveira, Frans Waanders, Luis F.O. Silva, Andre Jasper, Carlos H. Sampaio, Dursman Mchabe, Rachel S. Hatch, James C. Hower
Coal Combustion and Gasification Products Journal Archive
Seven feed coals used in the Brazilian power generation industry were obtained and subsequently analysed together with fly ash and bottom ash from a major Brazilian power plant. The samples were investigated by means of room temperature FeMo¨ssbauer analyses, X-ray diffraction, Raman spectroscopy, scanning electron microscope and petrographic analysis. In addition, nanometer-sized crystalline phases in coals and ashes were characterised using an energy-dispersive X-ray spectrometer and a high-resolution transmission electron microscope. The major identified Fe-bearing minerals in the coals were found to be actinolite, ankerite, chalcopyrite, chlorite, goethite, illite, ilmenite, magnesioferrite, natrojarosite, pyrite, pyrrhotite, and siderite; whilst in the fly …
Compositional Variations In Pilot Gasifier And Laboratory-Produced Slags And Their Impacts On Slag Viscosity And Coal Assessment, Alexander Ilyushechkin, Daniel Roberts, David Harris
Compositional Variations In Pilot Gasifier And Laboratory-Produced Slags And Their Impacts On Slag Viscosity And Coal Assessment, Alexander Ilyushechkin, Daniel Roberts, David Harris
Coal Combustion and Gasification Products Journal Archive
The flow behaviour of coal mineral matter at high temperatures is an important parameter for coal use in entrained-flow gasification technologies. Recently, gasification performance data was obtained from a series of pilot-scale gasification tests on a suite of well-characterised Australian black coals. Evaluation of the results of the pilot tests and the detailed laboratory investigations provided the opportunity for evaluation of the practical applicability of different laboratory and modelling techniques for coal assessment in terms of mineral matter behaviour in entrained flow gasification. A series of viscosity measurements was made over the range 1200–1600uC using slags produced in a pilot …
Compaction Of High-Ca Fly Ash-Al- And Al-Alloy-Composites: Evaluation Of Their Microstructure And Tribological Performance, Grigorios Itskos, Angeliki Moutsatsou, Pradeep K. Rohatgi, Nikolaos Koukouzas, Charalampos Vasilatos, Eleni Katsika
Compaction Of High-Ca Fly Ash-Al- And Al-Alloy-Composites: Evaluation Of Their Microstructure And Tribological Performance, Grigorios Itskos, Angeliki Moutsatsou, Pradeep K. Rohatgi, Nikolaos Koukouzas, Charalampos Vasilatos, Eleni Katsika
Coal Combustion and Gasification Products Journal Archive
In this study, highly calcareous and siliceous fly ash particles were utilized for the fabrication of Al- and Al-alloy-based MetalMatrix Composites (MMCs) by means of powder metallurgy. After compacting and sintering Al and Al/Si powders containing 10, 15, and 20wt. % ash particles, the homogenous (and with minimal amount of voids) microstructure of the produced composites was verified by means of Scanning Electron Microscopy (SEM). The composites were tested for their dry sliding wear behavior using a pin-on-disc machine against spheres of alumina. The worn surfaces of composites were then examined by using SEM and Energy Dispersive X-Ray Spectroscopy (EDS). …
Influence Of Chemical Reagents On Rheological Properties Of Fly Ash-Water Slurry At Varying Temperature Environment, H.K. Nail, M.K. Mishra, Karanam U.M. Rao
Influence Of Chemical Reagents On Rheological Properties Of Fly Ash-Water Slurry At Varying Temperature Environment, H.K. Nail, M.K. Mishra, Karanam U.M. Rao
Coal Combustion and Gasification Products Journal Archive
About 70% of total electrical energy is generated from thermal power plants in India which in turn release about 160 Mt of fly ash as solid waste annually. Transportation and disposal of such a huge amount of fly ash is a major problem faced by the power plants. Presently fly ash is transported as lean slurry in pipe lines requiring about 80 to 85% of water with high energy input. A major impediment in high volume transportation of fly ash is its high specific gravity as compared to that of water. The objective of the present study was to evaluate …
Impact Of Manufactured Coal Ash Aggregates On Water Quality During Open Pit Restoration: 1. A Statistical Screening Test, Sangchul Hwang, Isomar Latorre
Impact Of Manufactured Coal Ash Aggregates On Water Quality During Open Pit Restoration: 1. A Statistical Screening Test, Sangchul Hwang, Isomar Latorre
Coal Combustion and Gasification Products Journal Archive
Utilization of manufactured coal ash aggregates (MAs) as a subsoil substitute during restoration of an open pit was assessed in a three-factor, two-level factorial analysis. The factors of interest were the MA application rate (2:1 or 1:2 topsoil/MA volume ratio), rainfall intensity (high or low), and aggregate size (2.36–4.75 mm or 4.75–9.53 mm). Among the water quality parameters examined (pH, turbidity, heavy metal content (lead and cadmium), conductivity, and hardness), the last two parameters were significantly higher (p,0.05) in soil amended with MAs than in a control reactor using sand. A low rainfall intensity and larger aggregate size resulted in …
The Leachability Of Major Elements At Different Stages Of Weathering In Dry Disposed Coal Fly Ash, S.A. Akinyemi, A. Akinlua, W.M. Gitari, R.O. Akinyeye, L.F. Petrik
The Leachability Of Major Elements At Different Stages Of Weathering In Dry Disposed Coal Fly Ash, S.A. Akinyemi, A. Akinlua, W.M. Gitari, R.O. Akinyeye, L.F. Petrik
Coal Combustion and Gasification Products Journal Archive
Large quantities of solid residue are generated by coal-fired power stations in many parts of the World. The disposal and management of the unused fly ash remains a major problem to the environment. The weathered dry disposed ash cores comprise of major element constituents such as Al, Si, Ca, Mg, Fe, Mn, Na+ and K+. The mobility patterns and mineralogical associations of major elements in weathered dry disposed ash dumps aged 1-year-old, 8-year-old and 20-year-old from a coalfired power station in South Africa were investigated using a modified sequential extraction scheme. The extraction sequence was as follows: (1) water soluble, …
Testing Of Interactions Between Coal Ash Leachates And Rock Materials For Mine Backfill Evaluations, Colin R. Ward, David French, Leanne Stephenson, Ken Riley, Zhongsheng Li
Testing Of Interactions Between Coal Ash Leachates And Rock Materials For Mine Backfill Evaluations, Colin R. Ward, David French, Leanne Stephenson, Ken Riley, Zhongsheng Li
Coal Combustion and Gasification Products Journal Archive
A series of laboratory-based leaching tests has been developed to evaluate the chemical interaction between ash, water and different mine-site rock materials, as a basis for assessing the potential environmental impact of using coal ash as backfill in coal mines. Two different test protocols were used: a two-stage serial batch testing program in which leachate from representative ash samples were allowed to interact separately with relevant rock materials under laboratory conditions, and a single-stage mixed batch testing program in which 50:50 mixtures of the same ashes and rock samples were extracted with water following a similar procedure to leaching tests …
Chemistry Of Coal And Coal Combustion Products From Kentucky Power Plants: Results From The 2007 Sampling, With Emphasis On Selenium, James C. Hower, Thomas L. Robl, Gerald A. Thomas, Shelley D. Hopps, Margaret Grider
Chemistry Of Coal And Coal Combustion Products From Kentucky Power Plants: Results From The 2007 Sampling, With Emphasis On Selenium, James C. Hower, Thomas L. Robl, Gerald A. Thomas, Shelley D. Hopps, Margaret Grider
Coal Combustion and Gasification Products Journal Archive
Kentucky produced over 8 Mt of coal combustion products (CCPs) in 2006, with 30% of the CCPs being utilized, a significant increase from our 1996 and 2001 surveys. As much of the increase is related to increased utilization of flue-gas desulfurization (FGD) gypsum, the increased production of FGD gypsum coincident with the commissioning of new FGD units and the saturation of the (currently) weak market for new construction, the percentage of utilization may decrease by the time of the next planned survey (2011). The concentration of volatile trace elements in the feed coal and in the pulverizer reject, while associated …
An Investigation Of The Behavior Of Raw Calcareous Fly Ash In Mortar Mixtures, Ioanna Papayianni, Eleftherios K. Anastasiou
An Investigation Of The Behavior Of Raw Calcareous Fly Ash In Mortar Mixtures, Ioanna Papayianni, Eleftherios K. Anastasiou
Coal Combustion and Gasification Products Journal Archive
The behavior of unprocessed calcareous fly ash in cement mortar mixtures is often questionable and unpredictable and that is one of the difficulties in confining these fly ashes within the limits of standards. This work aims at correlating the material characteristics with its behavior in mortar mixtures. An effort is made to understand how three of the reactive constituents; lime (CaO), silica (SiO2), and sulfates (SO3), affect strength and volume stability. Two raw calcareous fly ashes of different composition emanating from the Ptolemaida area, Greece, were systematically tested to define their profile as cementitious agents that could be incorporated in …
Coal Fired Power Station Ash Products And Eu Regulation, Lindon K.A. Sear
Coal Fired Power Station Ash Products And Eu Regulation, Lindon K.A. Sear
Coal Combustion and Gasification Products Journal Archive
The UK has a long history of the use of coal fired power station ash products in a range of applications in construction. These range from use in concrete as a cementitious material through to its use as a fill material in embankments. While there have been no environmental problems associated with these uses, environmental regulations emanating from the European Union (EU) are increasingly impacting on the use of these materials. Unfortunately it is not a single set of regulations that are being applied, but three separate and apparently disconnected initiatives; these are Registration, Evaluation and Authorisation of Chemicals (REACH), …
Enriched Coal Ash Utilization For Augmenting Production Of Rice Under Acid Lateritic Soil, S. Karmakar, B.N. Mittra, B.C. Ghosh
Enriched Coal Ash Utilization For Augmenting Production Of Rice Under Acid Lateritic Soil, S. Karmakar, B.N. Mittra, B.C. Ghosh
Coal Combustion and Gasification Products Journal Archive
The use of industrial wastes such as fly ash (FA) or rice husk ash (RHA), along with paper factory sludge (PFS), farmyard manure (FYM), and chemical fertilizers (CF), under integrated nutrient management, was studied in acid lateritic soil on rice. Application of combined fertilization sources increased growth, yield attributes, and yield (up to 92.3 and 9.7% over control and CF, respectively) of wet season rice. The uptake of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and Co was increased under combined fertilization sources. The study also indicated that such integrated plant nutrition system improved physico-chemical properties of soil …
Erosive Wear In Pipelines At Pneumatic Conveying Of Fine Silicon-Containing Materials, Viacheslav Y. Putilov, Vijay K. Agarwal, Irina V. Putilova
Erosive Wear In Pipelines At Pneumatic Conveying Of Fine Silicon-Containing Materials, Viacheslav Y. Putilov, Vijay K. Agarwal, Irina V. Putilova
Coal Combustion and Gasification Products Journal Archive
Erosive wear is a major operational problem in conveying of hard abrasive bulk materials like silica sand, fly ash, coal dust, etc., in pneumatic conveying systems. Erosion results in emergency downtime of pneumatic conveying installations of ash and slag removal and dust-preparation systems at TPPs caused by holes in pipelines. That leads to worsening of technical, economic, and ecological parameters of thermal power plants as a whole. In MPEI, a model of estimating erosion of rectilinear and curvilinear sections of pneumatic conveying pipelines has been developed. To validate the estimating model developed in the MPEI, experimental investigations in the Indian …
Evaluation Of The Variables That Influence Mercury Capture In Solid Sorbents, M. Antonia Lopez-Anton, Patricia Abad-Valle, Mercedes Diaz-Somoano, M. Rosa Martinez-Tarazona
Evaluation Of The Variables That Influence Mercury Capture In Solid Sorbents, M. Antonia Lopez-Anton, Patricia Abad-Valle, Mercedes Diaz-Somoano, M. Rosa Martinez-Tarazona
Coal Combustion and Gasification Products Journal Archive
Newly obtained results on mercury retention in fly ashes and activated carbons during coal combustion are compared with previous findings. The influence of different variables on mercury capture, including the composition and nature of the sorbents, the composition of the flue gas and the mercury species in gas phase is investigated. Coal-fired utility boilers are currently the largest single-known source of mercury emissions. According to the USEPA’s Information Collection Request (ICR), on average, only 40% of the mercury entering a coal-fired power plant is captured, while 60% is emitted into the atmosphere. Several solid materials, including activated carbons, are considered …
Mechanical Performance Of Pavement Geomaterials Stabilized With Fly Ash In Field Applications, Lin Li, Tuncer B. Edil, Craig H. Benson
Mechanical Performance Of Pavement Geomaterials Stabilized With Fly Ash In Field Applications, Lin Li, Tuncer B. Edil, Craig H. Benson
Coal Combustion and Gasification Products Journal Archive
This paper describes an evaluation of the mechanical performance of fly ash stabilized materials. Soft clay soil, asphaltic recycled pavement material (RPM), and road-surface gravel (RSG) were stabilized using Class C and off-specification fly ashes to create working platforms or stabilized base courses for construction of flexible and rigid pavements at six sites in Wisconsin and Minnesota. California bearing ratio (CBR), resilient modulus (Mr) tests, and unconfined compression (qu) tests were conducted on the subgrade soil, RPM, and RSG alone and on mixtures prepared in the field and the laboratory to evaluate improvements in bearing resistance and stiffness. Fly ash …
Manufactured Coal Ash Aggregates For Aqueous Tnt Sorption, Sangchul Hwang, Victor Hernandez
Manufactured Coal Ash Aggregates For Aqueous Tnt Sorption, Sangchul Hwang, Victor Hernandez
Coal Combustion and Gasification Products Journal Archive
No abstract provided.
Mineralogy And Leaching Characteristics Of Coal Ash From A Major Brazilian Power Plant, Luis F.O. Silva, Colin R. Ward, James C. Hower, Maria Izquierdo, Frans Waanders, Marcos L.S. Oliveira, Zhongsheng Li, Rachel S. Hatch, Xavier Querol
Mineralogy And Leaching Characteristics Of Coal Ash From A Major Brazilian Power Plant, Luis F.O. Silva, Colin R. Ward, James C. Hower, Maria Izquierdo, Frans Waanders, Marcos L.S. Oliveira, Zhongsheng Li, Rachel S. Hatch, Xavier Querol
Coal Combustion and Gasification Products Journal Archive
The feed coals, fly ashes and bottom ashes collected from seven different units in a major Brazilian PF power plant have been subjected to comprehensive mineralogical, geochemical, and petrographic studies, to investigate the links between feed coal and ash characteristics. Ashes from two of the units were collected while the coal was being co-fired with oil as part of the boiler start-up procedure, allowing the impact of oil co-firing on ash characteristics also to be evaluated. High proportions of unburnt carbon and high proportions of retained sulphur were found in the fly ashes produced during oil co-firing, probably reflecting less …
Precipitation Of Germanium From Coal Fly Ash Leachates, Fatima Arroyo, Constantino Fernandez-Pereira, Pilar Coca
Precipitation Of Germanium From Coal Fly Ash Leachates, Fatima Arroyo, Constantino Fernandez-Pereira, Pilar Coca
Coal Combustion and Gasification Products Journal Archive
The valorization of a coal gasification fly ash was studied by leaching the fly ash using different aqueous solutions followed by the subsequent precipitation of the germanium solubilized from the ash. Experimental investigations were focused on the precipitation of a germanium2catechol (CAT) complex with cetyl trimethyl ammonium bromide (CTAB). The influences of pH and amounts of CTAB and CAT on the precipitation yield were investigated. To this aim, a central composite rotatable design and ANOVA Design Expert 7.0.3 Wiley software were employed for experimental design and analysis of the results. Thus, the independent and combined effects of pH, CAT/Ge and …
The Effect Of Drag-Reducing Additives On The Rheological Properties Of Fly Ash-Water Suspensions At Varying Temperature Environment, H.K. Naik, M.K. Mishra, Rao Karanam U.M.
The Effect Of Drag-Reducing Additives On The Rheological Properties Of Fly Ash-Water Suspensions At Varying Temperature Environment, H.K. Naik, M.K. Mishra, Rao Karanam U.M.
Coal Combustion and Gasification Products Journal Archive
Fly ash transportation and disposal is a major problem in India. Presently fly ash is being transported as lean slurry in pipe lines requiring about 80 to 85% of water which, in turn, consumes more energy input. The objective of the present study is to evaluate the rheological characteristics of fly ash slurry at varying temperatures with and without an additive to facilitate smooth flow in the pipelines. Six fly ash slurry samples were prepared from the fly ash obtained from a thermal power plant situated in the southern part of India. The main constituents of the slurry were fly …
Waste Stabilization/Solidification (S/S) Of Eaf Dust Using Fly Ash-Based Geopolymers. Influence Of Carbonation On The Stabilized Solids, Y. Luna Galiano, C. Fernandez Pereira, J. Vale
Waste Stabilization/Solidification (S/S) Of Eaf Dust Using Fly Ash-Based Geopolymers. Influence Of Carbonation On The Stabilized Solids, Y. Luna Galiano, C. Fernandez Pereira, J. Vale
Coal Combustion and Gasification Products Journal Archive
The effect of the curing in a carbonated ambient of the solids obtained after the stabilization/solidification (S/S) of metallurgical waste using geopolymerization technology is described in this paper. The electric arc furnace (EAF) dust to stabilize contains hazardous metals such as Pb, Cd, Cr, or Zn. Different geopolymeric agents such as potassium hydroxide, potassium silicate, metakaolin, and blast furnace slag have been used. Mixtures of EAF waste with these geopolymeric materials and class F fly ash as main silica and alumina source have been processed. Samples were submitted to an accelerated carbonation test. Compressive strength tests and different leaching tests …
Variations In Fly Ash Composition With Sampling Location: Case Study From A Portuguese Power Plant, B. Valentim, A. Guedes, D. Flores, C.R. Ward, J.C. Hower
Variations In Fly Ash Composition With Sampling Location: Case Study From A Portuguese Power Plant, B. Valentim, A. Guedes, D. Flores, C.R. Ward, J.C. Hower
Coal Combustion and Gasification Products Journal Archive
Fly ash (FA) is a heterogeneous and complex material resulting from coal combustion in thermoelectric power plants (TPP). Therefore, different types of coals, worldwide, produce FAs with different compositions. However, the location of the FA sampling system, inside the TPP, is also important to the composition of the FA produced at each location. A case study of FA from a Portuguese TPP, using several coal and FA characterization techniques (particle size analysis, proximate and ultimate analyses, XRF, SEM/ESEM/EDS, Optical microscopy, XRD, inferred chemistry, and AAS), has shown that FA chemical classification, mineralogy and phase-mineral classification, and trace elements (Cr, Cu, …
Zeolite Synthesised From Fused Coal Fly Ash At Low Temperature Using Seawater For Crystallization, Claudia Belviso, Francesco Cavalcante, Antonio Lettino, Saverio Fiore
Zeolite Synthesised From Fused Coal Fly Ash At Low Temperature Using Seawater For Crystallization, Claudia Belviso, Francesco Cavalcante, Antonio Lettino, Saverio Fiore
Coal Combustion and Gasification Products Journal Archive
A sample of coal fly ash from an Italian thermoelectric power plant was used in order to synthesize zeolite by hydrothermal activation after a pre-treatment fusion with NaOH. The experiments involved were performed at different temperatures of crystallization, ranging from 35 up to 60uC, with seawater and distilled water, separately, during hydrothermal process. A comparison between the results obtained from the use of the different kinds of water showed that at low temperature (35–40 uC) the synthesis yield of zeolite X is higher using seawater as crystallizing agent than using distilled water. This implies a possible application for seawater in …
Optical Properties Of Coal Combustion Byproducts For Particle-Size Analysis By Laser Diffraction, Robert B. Jewell, Robert F. Rathbone
Optical Properties Of Coal Combustion Byproducts For Particle-Size Analysis By Laser Diffraction, Robert B. Jewell, Robert F. Rathbone
Coal Combustion and Gasification Products Journal Archive
Laser diffraction analysis is commonly used for determining the particle-size distribution (PSD) of fly ash. However, there is currently no standard method for preparing samples and analyzing them. The Mie and Fraunhofer optical models are used to calculate the PSD of fly ash from laser diffraction data. The Mie theory is most applicable for particles smaller than 50 mm, and is therefore the most accurate model for the analysis of fly ash. However, the refractive index (RI) of fly ash is complex and not well known. This study presents the analysis of several supplementary cementitious materials (SCMs) such as coal …