Western Fly Ash Research, Development and Data Center

1985 ◽  
Vol 65 ◽  
Author(s):  
G. J. McCarthy ◽  
O. E. Manz ◽  
R. J. Stevenson ◽  
D. J. Hassett ◽  
G. H. Groenewold
Keyword(s):  
Fly Ash ◽  
North Dakota ◽  
Knowledge Base ◽  
Great Plains ◽  
Data Center ◽  
Bottom Ash ◽  
Low Rank ◽  
Research Development ◽  
High Calcium ◽  
By Products

With financial support from utilities and ash brokers*, the Western Fly Ash Research, Development and Data Center was established under the aegis of the North Dakota Mining and Mineral Resources Research Institute in August of 1985. Research will be performed by the two North Dakota universities in Grand Forks and Fargo. The fundamental objective of the Center is to enhance the knowledge base of the properties (chemical, mineralogical and physical) and reactions of the coal by-products (principally fly ash, but including bottom ash and FGD waste) produced in the Midwestern and Great Plains regions of the US. Most of the study specimens will be high-calcium (ASTM Class C) ash derived from low-rank lignite and subbituminous coals mined in North Dakota, Montana and Wyoming, although ash from other regions and coals is also being studied. The enhanced knowledge base should lead to more widespread utilization of these by-products [1,2] or, where this is necessary, to their safe and cost-effective disposal [3].

Correlations of Chemistry and Mineralogy of Western U.S. Fly Ash

1986 ◽  
Vol 86 ◽  
Author(s):  
G. J. McCarthy ◽  
O. E. Manz ◽  
D. M. Johansen ◽  
S. J. Steinwand ◽  
R. J. Stevenson
Keyword(s):  
Fly Ash ◽  
Physical Properties ◽  
North Dakota ◽  
Data Center ◽  
Low Rank ◽  
Research Development ◽  
X Ray Diffraction ◽  
Fly Ashes ◽  
X Ray ◽  
Low Rank Coals

Fly ashes derived from low-rank coals mined principally in Montana, Wyoming and North Dakota are being studied by the Western Fly Ash Research, Development and Data Center [1]. Previous studies of the mineralogy of western U.S. fly ash by McCarthy et al. [1–3] using x-ray diffraction (XRD) form the framework of the present study. A database of chemical, mineralogical and physical properties, along with precursor coal characteristics, is being assembled. Based on studies to date of several hundred fly ash samples derived from lignite and subbituminous coals, as well as from several bituminous ashes, correlations of chemistry and mineralogy have been hypothesized and are being tested. These correlations are discussed below.

Technical Basis for Codisposal of Gasification and Combustion Ash from the Plants at Beulah, North Dakota

1985 ◽  
Vol 65 ◽  
Author(s):  
G. J. McCarthy ◽  
D. J. Hassett ◽  
O. E. Manz ◽  
G. H. Groenewold ◽  
R. J. Stevenson ◽  
...  
Keyword(s):  
North Dakota ◽  
Great Plains ◽  
Tap Water ◽  
Day Treatment ◽  
Bottom Ash ◽  
Weighted Average ◽  
Reaction Products ◽  
Mineralogical Characterization ◽  
Curing Conditions ◽  
Solid Ratio

ABSTRACTThe technical hasis for codisposal of gasification ash from the Great Plains Gasification Associates plant, combined with cementitious “scrubber ash” and bottom ash from the adjoining Antelope Valley generating station, both located in Beulah, North Dakota, has been explored. Nine blends containing only the ashes and tap water were fabricated into cylinders and tested for compressive strength and other physical properties. A blend having the ash proportions of the two plants was tested for leachability with respect to several regulated and minor elements. Mineralogical characterization by XRD was performed on the individual waste solids and the cured mixes. Most of the blends had compressive strengths greater than 400 psi after 7-day/38 C and 28-day/21 C curing. The 7-day treatment led to better consolidated test cylinders. Leaching behavior, evaluated by the EPA-EP and ASTM tests, was determined for As, Se, B, V, Mo, Ba, Sr, and K. Average fixation factors (the ratio of leaching expected from a weighted average of its components to the actual leaching of the specimen) of 2 to 4 were observed for the 7-day cured specimens and 1 to 2 for the 28-day specimens. Not all elements had reduced leaching in the fabricated specimens; Se and V leaching increased in the fabricated specimens. In addition to ash proportions, curing conditions (T, pH2O, time) and water to solid ratio appear to key parameters in obtaining well-consolidated and lower leachability products. XRD indicated that ettringite and minor calcite were the only crystalline reaction products of the cementitious reactions in the cured codisposal mix.

Influences of the Ratios of High-Calcium Fly Ash to Low-Calcium Fly Ash on the Strength and Drying Shrinkage of Geopolymer Mortar

2014 ◽  
Vol 931-932 ◽  
pp. 416-420 ◽  
Author(s):  
Ridtirud Charoenchai ◽  
Prinya Chindaprasirt
Keyword(s):  
Fly Ash ◽  
Power Plants ◽  
Setting Time ◽  
Drying Shrinkage ◽  
High Calcium ◽  
High Calcium Fly Ash ◽  
Class C ◽  
Class F Fly Ash ◽  
By Products ◽  
Class F

New types of binders are being developed as an alternative to traditional cement. These alternatives are developed to have better properties and to be more environmentally friendly. Geopolymer is a novel binder that is produced from by-products such as fly ash, rich hushes ash and bio mass ash. In this experiment, fly ash, which was a by-product from electrical-generating power plants, was used during the synthesis of geopolymer. According to ASTM standard C168, fly ash is categorized into two types: class F and class C. This research focuses on the effects of using both types of fly ashes on mechanical properties of geopolymer. The experiment studies the changes on setting time, drying shrinkage and compressive strength of geopolymer mortar when 0, 25, 50, 75 and 100 percent of total weight of class F fly ash (LCF) is substituted with class C counterpart (HCF). The study used sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) as alkali activators. The samples were cured for 24 hours either at an ambient temperature of 25°C or at an elevated temperature of 60°C.The result showed that the setting time of pure LCF geopolymer mortar was 6 times longer than that of the pure HCF ones. In addition to setting time, the specimens with 25 percent of their total binders weight replaced by HCF appeared to have the highest strength. However, the increase in HCF also increased the drying shrinkage by 6 and 12times when the specimens were cured at25°C and at 60°C respectively

The effectiveness of industrial by-products to stop phosphorous loss from a Pallic soil

Soil Research ◽  
2004 ◽  
Vol 42 (7) ◽  
pp. 755 ◽  
Author(s):  
R. W. McDowell
Keyword(s):  
Fly Ash ◽  
Overland Flow ◽  
Bottom Ash ◽  
Loss Mitigation ◽  
Olsen P ◽  
P Loss ◽  
Steel Manufacturing ◽  
Soluble P ◽  
Current Guidelines ◽  
By Products

A study was conducted of the effectiveness of applying various rates (0–50 g/kg) of fly and bottom ash (<2 mm and 2–4 mm) from a coal-fired power plant, and melter (AP10B and PAP5) and basic (KOBM) slags from a steel-manufacturing plant on mitigating phosphorus (P) loss from a Pallic soil sown to pasture. Measurements were made of soil pH, Olsen P, and H2O-P (as a measure of P loss in overland flow), and soluble P and contaminants (B, As, Cd, Pb, Se) from a weekly leaching regime for 9 weeks. Results shows that H2O-P had decreased up to 40% in soils treated at the greatest rate of melter slag (50 g/kg), and increased in KOBM and fly ash treated soils. The effect on Olsen P relative to H2O-P was much less in metler slag and bottom ash treated soils than soils treated with fly ash or KOBM slag. The fly ash was considered unsuitable for the mitigation of P loss from soils due to B toxicity to plants, while KOBM is also unsuitable due to a liming effect and the increase in soluble P loss. At the rates applied, no treated soil leached toxic metals (As, Cd, Hg, or Se) above current guidelines. In contrast, the incorporation of melter slag and bottom ash is considered an effective P loss mitigation strategy.

scholarly journals Petrographic Characteristics of Coal Gasification and Combustion by-Products from High Volatile Bituminous Coal

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4374
Author(s):  
Barbara Bielowicz
Keyword(s):  
Fly Ash ◽  
Coal Gasification ◽  
Management Strategies ◽  
Bottom Ash ◽  
Mineral Matter ◽  
Petrographic Analysis ◽  
Petrographic Composition ◽  
Gasification Products ◽  
Combustion Processes ◽  
By Products

The coal was gasified in a fluidized bed reactor with CO2 as a gasifying agent at 889–980 °C. The coal and gasification residue produced during gasification was burned at temperatures up to 900 °C. The petrographic analysis, gasification residues, and fly and bottom ash resulting from the combustion of coal and chars showed the efficiency of the gasification and combustion processes. The gasification residue primarily comprised inertoids and crassinetwork, which accounted for 60% of the sample. The analysis of the petrographic composition of fly ash revealed that the fly ash formed during the combustion of gasification residue had a higher mineral content. The fly ash from the combustion of gasification products contained significantly less unburned coal compared to that from coal. The samples of the bottom ash from coal combustion were composed of approximately 25% organic matter, most of which was chars. The bottom ash formed from the combustion of coal gasification products was composed mainly of mineral matter (95% or higher). The obtained results have significant implications in determining future waste management strategies.

scholarly journals Characteristics of Waste Iron Powder as a Fine Filler in a High-Calcium Fly Ash Geopolymer

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2515
Author(s):  
Toon Nongnuang ◽  
Peerapong Jitsangiam ◽  
Ubolluk Rattanasak ◽  
Weerachart Tangchirapat ◽  
Teewara Suwan ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Flexural Strength ◽  
Iron Powder ◽  
Construction Material ◽  
Setting Time ◽  
Bottom Ash ◽  
Curing Process ◽  
Heat Curing ◽  
High Calcium

Geopolymer (GP) has been applied as an environmentally-friendly construction material in recent years. Many pozzolanic wastes, such as fly ash (FA) and bottom ash, are commonly used as source materials for synthesizing geopolymer. Nonetheless, many non-pozzolanic wastes are often applied in the field of civil engineering, including waste iron powder (WIP). WIPs are massively produced as by-products from iron and steel industries, and the production rate increases every year. As an iron-based material, WIP has properties of heat induction and restoration, which can enhance the heat curing process of GP. Therefore, this study aimed to utilize WIP in high-calcium FA geopolymer to develop a new type of geopolymer and examine its properties compared to the conventional geopolymer. Scanning electron microscopy and X-ray diffraction were performed on the geopolymers. Mechanical properties, including compressive strength and flexural strength, were also determined. In addition, setting time and temperature monitoring during the heat curing process were carried out. The results indicated that the addition of WIP in FA geopolymer decreased the compressive strength, owing to the formation of tetrahydroxoferrate (II) sodium or Na2[Fe(OH)4]. However, a significant increase in the flexural strength of GP with WIP addition was detected. A flexural strength of 8.5 MPa was achieved by a 28-day sample with 20% of WIP addition, nearly three times higher than that of control.

Radiometric measurement of lignite coal and its by-products and assessment of the usability of fly ash as raw materials in Turkey

2018 ◽  
Vol 106 (7) ◽  
pp. 611-621 ◽  
Author(s):  
Şeref Turhan ◽  
Elif Gören ◽  
Ahmed M.K. Garad ◽  
Aydan Altıkulaç ◽  
Aslı Kurnaz ◽  
...  
Keyword(s):  
Fly Ash ◽  
Gamma Ray ◽  
Raw Materials ◽  
Bottom Ash ◽  
Chemical Components ◽  
The Public ◽  
Activity Concentrations ◽  
Lignite Coal ◽  
Major Chemical ◽  
By Products

Abstract Lignite coal (LC) is a key energy source for electricity generation in Turkey. During lignite burning, huge amounts of fly ash (FA), bottom ash and slag are produced as by-products which contain radionuclides in the natural radioactive series of uranium and thorium, and radioactive potassium. These radionuclides may lead to radiological exposure of workers and the public and cause environmental problems. Therefore, finding diverse uses for the by-products in the construction sector and earthwork applications has considerable economic and environmental importance. In this study, the activity concentrations of 226Ra, 232Th and 40K in and radon emanating power (EP) and radon mass exhalation rate (EXRM) from LC, slag and FA obtained from the Kangal lignite-burning power plant with a power of 457 MWe were measured using gamma-ray spectroscopy. The major chemical components (SiO2, Al2O3, Fe2O3, CaO and MgO) of fly ash samples were analysed using an energy dispersive X-ray fluorescence spectrometer. The annual effective doses received by workers and members of the public were estimated using different scenarios specified in Radiation protection 122. The average activity concentrations of 226Ra, 232Th and 40K in LC, slag and FA samples were 187±21, 16±1 and 99±9 Bq kg−1, 620±18, 41±2 and 330±13 Bq kg−1, and 937±30, 38±2 and 272±17 Bq kg−1, respectively. The average values of EP and EXRM of the lignite, slag and FA samples were 8 %, 7 % and 10 %, and 0.1, 0.3 and 0.7 Bq kg−1 h−1, respectively. The highest average of the total annual effective dose is estimated at 153 μSv for members of the public and 74 μSv for workers, lower than the recommended annual limit of 1000 μSv.

scholarly journals Slag and ash chemistry after high-calcium lignite combustion in a pulverized coal-fired power plant

2013 ◽  
Vol 9 (1) ◽  
pp. 77-82 ◽  
Keyword(s):  
Fly Ash ◽  
Power Plant ◽  
Inductively Coupled Plasma ◽  
Power Plants ◽  
Bottom Ash ◽  
Calorific Value ◽  
Emission Spectrometry ◽  
Northern Greece ◽  
Inorganic Matter ◽  
High Calcium

More than 73% of the electrical power requirements of Greece are generated in lignite-fired power plants. Greece is the thirteenth largest coal and the fifth largest lignite producer in the world. The lack of domestic high-rank coals makes necessary to use low quality lignite for power generation in Greece. These lignites are characterized by a high water and ash content and a low calorific value. The low quality of such lignites generates important technical and environmental problems during combustion. Slagging and fouling are common inside the power units and affect with particular severity the power plants performance. Slagging deposits take place in the high temperature radiant sections of the boiler, and are usually associated with some degree of melting of the ash. Fouling deposits are produced in the lower temperature convective sections of the boiler, and are generally related to condensation on the low temperature tube surfaces. Problems in boilers associated with ash deposits include modification of the heat transfer in different sections of the furnace, physical distortion of metal pieces due to the weight of the deposit, clogging of burners, and corrosion and erosion of metal walls. Feed lignite always carries more than 20% of inorganic matter, and its mineralogy and chemistry are originally related to geological factors. Five representative samples were collected from the inner surfaces of Unit 1 of the Agios Dimitrios Power Plant, Northern Greece, reflecting the main types of ash deposits occurring in the combustion facility. The chemistry of these high-calcium ash deposits has been investigated. Moreover, a fly ash and a bottom ash samples were taken and analyzed in order to investigate their possible impact on the environment after land-filling. All samples were digested by using 2.5 ml HNO3, 5ml HF and 2.5 ml HClO4 (1:2:1). Sixty element concentrations were determined in all samples by inductively coupled plasma–mass spectrometry (ICP–MS) and inductively coupled plasma – optical emission spectrometry (ICP-OES). Calcium is the most abundant element in all samples due to the dominance of calcium phases. The chemical composition of the bottom ash, fly ash, slag and fouling deposits, is mainly influenced by the chemical composition of the feed lignite and the co-excavated sterile materials, which are marly limestones containing, on average, 93% of calcite.

Characterization of lead-bearing phases in municipal waste combustor fly ash

1996 ◽  
Vol 54 ◽  
pp. 516-517
Author(s):  
L. L. Sutter ◽  
G. R. Dewey ◽  
J. F. Sandell
Keyword(s):  
Fly Ash ◽  
Bottom Ash ◽  
Municipal Waste ◽  
Primary Concern ◽  
Leaching Behavior ◽  
Waste Combustion ◽  
Lead And Cadmium ◽  
Lead Speciation ◽  
Accepted Practice

Municipal waste combustion typically involves both energy recovery as well as volume reduction of municipal solid waste prior to landfilling. However, due to environmental concerns, municipal waste combustion (MWC) has not been a widely accepted practice. A primary concern is the leaching behavior of MWC ash when it is stored in a landfill. The ash consists of a finely divided fly ash fraction (10% by volume) and a coarser bottom ash (90% by volume). Typically, MWC fly ash fails tests used to evaluate leaching behavior due to high amounts of soluble lead and cadmium species. The focus of this study was to identify specific lead bearing phases in MWC fly ash. Detailed information regarding lead speciation is necessary to completely understand the leaching behavior of MWC ash.

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