scholarly journals ENVIRONMENTAL GEOCHEMISTRY OF PTOLEMAIS LIGNITES, INTERMEDIATE STERILES, AND COMBUSTION PRODUCTS

2017 ◽  
Vol 50 (4) ◽  
pp. 2241
Author(s):  
P. Megalovasilis ◽  
A. Godelitsas ◽  
G. Papastergios ◽  
A. Filippidis
Keyword(s):  
Trace Elements ◽  
Fly Ash ◽  
Bottom Ash ◽  
Environmental Geochemistry ◽  
Combustion Products ◽  
Major Elements ◽  
Chemical Analyses ◽  
Micro Particles

The environmental geochemistry of lignite, intermediate sterile, fly ash and bottom ash samples from Ptolemais area, has been investigated. The chemical analyses of major elements, combined with SEM-EDS, showed that Si, Ca and Fe, are the most abundant elements and associated with various micro-particles. On average, the most abundant trace elements in the lignite samples are Ba (128 ppm), V (123 ppm), Cr (108 ppm), Sr (107), Ni (43 ppm), in intermediate sterile samples Ba (209 ppm), Sr (209 ppm), Cr (104 ppm), Ni (76 ppm), Zr (67 ppm), Zn (57 ppm), V (53 ppm), in fly ash samples Ba (455 ppm), Sr (336 ppm), Ni (180 ppm), Cr (160 ppm), V (110 ppm), Zr (102 ppm), Zn (74 ppm), Cu (71 ppm), Rb (62 ppm) and in bottom ash samples Ba (250 ppm), Cr (214 ppm), V (174 ppm), Sr (153 ppm), Ni (105 ppm), Zr (56 ppm), Zn (40 ppm)

Behavior study of trace elements in pulverized lignite, bottom ash, and fly ash of Amyntaio power station, Greece

2012 ◽  
Vol 185 (7) ◽  
pp. 6071-6076 ◽  
Author(s):  
Pavlos Megalovasilis ◽  
Georgios Papastergios ◽  
Anestis Filippidis
Keyword(s):  
Trace Elements ◽  
Fly Ash ◽  
Bottom Ash ◽  
Power Station ◽  
Behavior Study

scholarly journals Research Summary on the Processing, Mechanical and Tribological Properties of Aluminium Matrix Composites as Effected by Fly Ash Reinforcement

Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1212
Author(s):  
Alaa Mohammed Razzaq ◽  
Dayang Laila Majid ◽  
Uday M. Basheer ◽  
Hakim S. Sultan Aljibori
Keyword(s):  
Composite Materials ◽  
Fly Ash ◽  
Power Plants ◽  
Bottom Ash ◽  
Metallic Matrix ◽  
Weight Fraction ◽  
Combustion Products ◽  
Coal Waste ◽  
Matrix Composites ◽  
Coal Combustion Products

Fly ash is the main waste as a result of combustion in coal fired power plants. It represents about 40% of the wastes of coal combustion products (fly ash, boiler ash, flue gas desulphurization gypsum and bottom ash). Currently, coal waste is not fully utilized and waste disposal remains a serious concern despite tremendous global efforts in reducing fossil fuel dependency and shifting to sustainable energy sources. Owing to that, employment of fly ash as reinforcement particles in metallic matrix composites are gaining momentum as part of recycling effort and also as a means to improve the specifications of the materials that are added to it to form composite materials. Many studies have been done on fly ash to study composite materials wear characteristics including the effects of fly ash content, applied load, and sliding velocity. Here, particular attention is given to studies carried out on the influence FA content on physical, mechanical, and the thermal behavior of Aluminium-FA composites. Considerable changes in these properties are seen by fly ash refinement with limited size and weight fraction. The advantage of fly ash addition results in low density of composites materials, improvement of strength, and hardness. It further reduces the thermal expansion coefficient and improve wear resistance.

scholarly journals Mineralogical and Chemical Characteristics of Coal Ashes from Two High-Sulfur Coal-Fired Power Plants in Wuhai, Inner Mongolia, China

Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 323 ◽  
Author(s):  
Qiang Wei ◽  
Weijiao Song
Keyword(s):  
Trace Elements ◽  
Inner Mongolia ◽  
Power Plants ◽  
Bottom Ash ◽  
Distribution Patterns ◽  
Combustion Products ◽  
Chemical Characteristics ◽  
Fly Ashes ◽  
Coal Combustion Products ◽  
Coal Ashes

The mineralogical and chemical characteristics of the feed coals and coal combustion products (CCPs) from two power plants (Xilaifeng and Damo) that consume coals from the Wuda Coalfield, Inner Mongolia, were investigated, using XRD, SEM–EDS, XRF, and ICP-MS. The feed coals from Xilaifeng and Damo are both of high ash yield (52.93% and 48.36%, respectively), and medium and high total sulfur content (2.22% and 3.32%, respectively). The minerals in the feed coals are primarily composed of kaolinite, quartz, illite, pyrite, and, to a lesser extent, gypsum and anatase. In addition to the elevated incompatible elements (Nb, Ta, Zr, Hf and Th), Li and Hg are enriched in the feed coals from the Xilaifeng and Damo power plants, respectively. Rare earth elements and yttrium (REY) are more enriched in the feed coals from Xilaifeng (194 μg/g) than those of Damo (93.9 μg/g). The inorganic phases of CCPs from both power plants are mainly composed of amorphous phase, quartz, hematite, illite, and anhydrite. Compared with the feed coals, concentrations of most trace elements in the CCPs are elevated, and they are preferentially enriched in the fly ashes relative to the bottom ashes (*f/b > 1), especially F, As, Sr, Mo, Se, and Hg (*f/b > 2.5). Furthermore, most trace elements (Xilaifeng: excluding Li, Cr, Co, Ni, Rb, Nb and Cs; Damo: excluding Li, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Cs and Ba) are more enriched in the (fine) fly ashes relative to the laboratory high-temperature coal ashes (HTAs). The REY barely differentiate in either the fly ash or bottom ash from Xilaifeng. In contrast, the REY in the fine and coarse fly ashes from Damo have very similar H-type distribution patterns with negative Ce and slightly positive Y anomalies. Attention should be paid to the enriched toxic elements (including F, As and Hg) in the fly ashes from both power plants due to possible adverse environmental effect.

Partitioning of Trace Elements During Fluidized Bed Combustion of High Ash Content Lignite

2005 ◽  
Author(s):  
Nevin Selc¸uk ◽  
Yusuf Gogebakan ◽  
Zuhal Gogebakan
Keyword(s):  
Trace Elements ◽  
Fly Ash ◽  
Fluidized Bed ◽  
Inductively Coupled Plasma ◽  
Bottom Ash ◽  
Ash Content ◽  
Fluidized Bed Combustion ◽  
Test Rig ◽  
Minor Elements ◽  
Element Partitioning

The behavior of 20 trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and 8 major and minor elements (Al, Ca, Fe, K, Mg, Na, Si, Ti) during the combustion of high ash content lignite with and without limestone addition have been investigated in the 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) Test Rig. Experiments were performed without fines recycle. Inert bed material utilized in the experiments was bed ash obtained previously from the combustion of the same lignite without limestone addition in the same test rig. Concentrations of trace elements in coal, limestone, bottom ash, cyclone ash and filter ash were determined by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Measurements show that the distribution of major and minor elements follows the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Cr, Hg, Li, Mo, Ni, Sn, V, Zn) are recovered in fly ash. Comparisons between the trace element partitioning of the runs with and without limestone addition reveal that addition of limestone shifts the partitioning of Ba, Cr, Hg, Mo, Ni, Sn, V, Zn from bottom ash to fly ash.

scholarly journals Mineralogy and chemical composition of technogenic soils (Technosols) developed from fly ash and bottom ash from selected thermal power stations in Poland

2015 ◽  
Vol 66 (2) ◽  
pp. 82-91 ◽  
Author(s):  
Łukasz Uzarowicz ◽  
Zbigniew Zagórski
Keyword(s):  
Fly Ash ◽  
Chemical Composition ◽  
Iron Oxides ◽  
Mineral Composition ◽  
Coal Combustion ◽  
Bituminous Coal ◽  
Bottom Ash ◽  
Major Elements ◽  
Soil Horizons ◽  
Technogenic Soils

Abstract The aim of the study was to determine the mineral and chemical composition of technogenic soils (Technosols) developed from fly ash and bottom ash from power plants in which bituminous coal and lignite was combusted. The mineral composition of the “fresh” wastes (i.e. fly ash and bottom ash) and soil samples derived from them was examined by X-ray diffraction (XRD) and using a scanning electron microscope (SEM). The chemical composition (content of major elements) was determined using ICP-AES method. Quartz, mullite, and amorphous substances (glass) predominated in the mineral composition of wastes after bituminous coal combustion. Magnetite was also found there. Soils developed from wastes after bituminous coal combustion contained all above mentioned minerals inherited from fly ash and bottom ash. Moreover, small amounts of secondary calcite were identified. In some soil horizons containing large amounts of inherited magnetite, secondary iron oxides and oxyhydroxides (goethite and lepidocrocite) also occurred. Quartz predominated in the mineral composition of the “fresh” wastes after lignite combustion. Relatively small amounts of iron oxides (magnetite and hematite) were also found there. In “fresh” fly ash, apart from minerals mentioned above, anhydrite and calcium oxide (lime) was identified. Soils developed from wastes after lignite combustion contained inherited quartz, magnetite, and hematite. Furthermore, calcite which sometimes was a predominating mineral in certain soil horizons occurred. Moreover, sulphates (gypsum, bassanite, and ettringite), and vaterite (a polymorph of Ca carbonate) were also found in soils. Silicon predominated among major elements in “fresh” ashes after bituminous coal combustion and soil derived from them followed by Al, Fe, K, Ca, Mg, Ti, Na, P, and Mn. On the other hand, the contents of major elements in the samples (ashes and soils) after lignite combustion can be arranged as follows: Si, Ca, Fe, Al, Mg, Ti, K, Mn, Na, and P. However, in some horizons (i.e. in calcareous materials deposited in the topsoil of some profiles) in soil developed on landfills near TPSs combusting lignite, Ca was a predominating element.

Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures

2002 ◽  
Author(s):  
Warren Dick ◽  
Yona Chen ◽  
Maurice Watson
Keyword(s):  
Fly Ash ◽  
Coal Combustion ◽  
Bottom Ash ◽  
Coal Ash ◽  
Combustion Products ◽  
The United States ◽  
Growth Media ◽  
Fgd Gypsum ◽  
Animal Manures ◽  
The Us

Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.

Comparison of the Behavior of Trace Elements During Acid Leaching of Ashes from Several Coals

1986 ◽  
Vol 86 ◽  
Author(s):  
J. S. Watson
Keyword(s):  
Trace Elements ◽  
Fly Ash ◽  
Amorphous Materials ◽  
Acid Leaching ◽  
Initial Step ◽  
Mineral Acid ◽  
Chemical Analyses ◽  
Leaching Behavior ◽  
Original Distribution ◽  
Strong Mineral Acid

ABSTRACTThe leaching of fly ash from eastern U.S. coals with strong mineral acid is the initial step in a series of potential processes for producing useful and marketable materials from the ash. This initial leaching step removes most, or all, of the more soluble (generally amorphous) materials from the ash and leaves an inert residue, believed to be mostly mullite and silica. Chemical analyses of the leachate and the residual inert materials indicate the original distribution of the trace elements in the phases. Significant differences in crystallography, composition and leaching behavior have been noted in ash samples from coals from various regions, of various types, and sometimes even in ash samples from the same or similar coals. Trace element analyses of fly ash leachates provide a useful means of studying coal characteristics and of determining how the trace elements are incorporated in various types of fly ashes.

scholarly journals Mineralogical and Environmental Geochemistry of Coal Combustion Products from Shenhuo and Yihua Power Plants in Xinjiang Autonomous Region, Northwest China

Minerals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 496 ◽  
Author(s):  
Wu ◽  
Li ◽  
Zhuang ◽  
Querol ◽  
Moreno ◽  
...  
Keyword(s):  
Fly Ash ◽  
Coal Combustion ◽  
Inductively Coupled Plasma ◽  
Power Plants ◽  
Environmental Geochemistry ◽  
Combustion Products ◽  
Coal Combustion Products ◽  
X Ray ◽  
Inductively Coupled ◽  
Xinjiang Autonomous Region

The mineralogical and geochemical characteristics of feed coals and coal combustion products (CCPs) from the Shenhuo and Yihua Power Plants in Xinjiang Autonomous Region, were studied by means of proximate analysis, Power X-ray diffraction (XRD), scanning electron microscopy with Energy Dispersive X-ray analyzer (SEM-EDX), inductively coupled plasma atomic emission spectrometry (ICP-MS) and inductively coupled plasma mass spectrometry (ICP-AES). The environmental geochemistry of CCPs was evaluated by Al-normalized enrichment factor as well as European Standard EN-12457 leaching test. Two feed coals have the characteristics of low sulfur content, medium to high volatiles matter yields, medium moisture content, super low to medium ash yield, medium to high calorific value and low mineral content. The main crystalline facies in fly ash and slag are quartz and mullite, with a small amount of calcite, and some unburned carbon. Hematite, SrSO4 and barite also can be observed in fly ashes by SEM. Typical plerophere occurs in fine fly ash rather than the coarse fly ash. The concentration of most trace elements in CCPs falls within the lower concentration range of European fly ashes. With respect to the partitioning behavior of trace elements during coal combustion, S is highly volatile, and Mg, Na, Zn, B, Co, As, Nb, Zr, Cu and K also show certain volatility, which may to some extent emit to the atmosphere. Furthermore, leaching experiments show that leachable concentrations of most of the potentially toxic elements in CCPs are low, and the CCPs fall in the range between inert and nonhazardous landfill material regulated by the 2003/33/EC Decision.

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