MSW incineration fly ash (FA) is generated from air pollution control systems for flue gas. With the continuous improvement of air pollution controls, the FA collected …
The heat of hydration, mechanical properties, pozzolanic activity, and microscopic characteristics of cement pastes incorporating co-combusted fly ash (CCFA) were investigated, and the disparities between the CCFA/cement system and the coal fly ash (CFA) binding system were also compared. The results indicate a decrease in the …
Various physico-chemical properties such as particle size distribution, specific gravity, specific surface area, chemical composition, solubility of Fly Ash (FA) in NaOH and pozzolanic activity of fly ash towards lime have …
generated by human activities. About 0.5 kg samples at a depth of 15–20 cm from each grid sampling of 4 m * 4m was mixed together and kept in a self-closing plastic bag. Wooden shovel was used to collect the fly ash samples to avoid the heavy metal contamination from the metal tools. Analysis of core samples of cement-solidified FA …
In this study, the effects of silicate modulus of activators (Ms) on carbonation of alkali-activated slag/fly ash cements are studied and compared between natural (0.03–0.04% CO 2) and accelerated (1% CO 2) carbonation conditions, via XRD, FTIR and TG/DTG techniques.Carbonation results in the decalcification of the C-A-S-H gels and …
Affiliations 1 Key Laboratory for Solid Waste Management and Environment Safety, School of Environment, Tsinghua University, Beijing, PR China.; 2 Key Laboratory for Solid Waste Management and Environment Safety, School of Environment, Tsinghua University, Beijing, PR China. Electronic address: [email protected].
1 Bond characteristics between early aged fly ash concrete and reinforcing steel bar after fire Qingtao Lia, Xiaohua Huangb, Zhaohui Huangc*, Guanglin Yuanb a State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou, 221116, China
Fly ash (FA) is the principal industrial waste byproduct from the burning of solid fuels. FA is a powdery solid that is constituted mostly of unburned carbon (UC), …
Among the 261 child participants, there were more males than females (52.1% vs. 47.9%), the majority were white (74.3%), and the average age was 10.7 years old (Table 1.)Twenty percent of children ...
This study focused on characterizing the carbonation behavior of 90-day aged alkali-activated fly ash/slag blended by MgO. Effects of MgO reactivity on the …
The dissolution and release of active ions, such as Si 4+, Al 3+ and Ca 2+, from fly ash directly affect the rate and extent of reaction product formation, which in …
The index of ash activity was calculated on samples aged 28 days, data on the compressive strength of heavy concrete samples prepared with the replacement of a part of the cement with the studied ...
Fly ash for concrete - Part 1: Definition, specifications and conformity criteria, German version: 2012: China: GB/T 1596: Fly ash used for cement and concrete: 2017: The Table 5 lists the properties of FA used in some studies. ... The activity of admixtures mostly influenced the rate of hydration. In this study, slag had higher activity than ...
The chemical composition of fly ash and zeolites were determined by means of XRF. The sum of main oxides indicates that the tested material is an F-class fly ash (alumino-silicate) according to ASTM C618-08 (2008) [].Herein, in order to produce high-purity zeolite, the fly ash raw material was subjected to a certain pre-treatment process, …
fly ash from local power plant for crop planting. The coal fly ash soil layer ranged from 40 to 60 cm. Preliminary investigation showed that the contents of cadmium (Cd), lead (Pb) and mercury (Hg) in the local coal fly ash farm-land exceeded Hebei average contents in top soil. Crop yield directly planted in the coal fly ash soil was very low.
In this work, the settling performance and properties of activated sludge were studied in the presence of fly ash. Upon mixing, fly ash increased the zeta potential of …
Introduction Fly ash is a waste product generated from burning coal for electricity. It is comprised of spherical particles ranging in size from 0.1 µm to over 100 µm in diameter that contain trace levels of heavy metals. Large countries such as China and India generate over 100 million tons per year while smaller countries like Italy and France generate 2 to 3 …
Fly ash (FA) is finely divided by-product precipitated electrostatically from the combustion of pulverized coal in the thermal power plants. The hydration of four mixes of fly ash-lime 90:10, 80: ...
Leaching of arsenic from ash in coal fly ash disposal facilities is a cause for concern due to possible contamination of groundwater. Sequential batch and column leaching experiments were carried out to determine the leaching of arsenic from ash found at a retired ash impoundment basin near a coal-fired power plant. This study assessed the leaching …
For aged sediments containing 2% BCs, the sorption capacity was 9.15- and 2.87-fold higher than that of FC when supplemented with RC aged at 25 and 45 °C, respectively. Therefore, biochar is better than fly ash for controlling organic pollutants even when the RC was present in sediment for a long time.
Can the magnetic signatures from inorganic fly ash be used to mark the onset of the Anthropocene? The Anthropocene Review, 1–11, 10.1177/20530 (2014).
Aided phytostabilization using coal fly ashes (CFAs) is an interesting technique to clean-up polluted soils and valorizing industrial wastes. In this context, our work aims to study the effect of two CFAs: silico-aluminous (CFA1) and sulfo-calcic (CFA2) ones, 10 years after their addition, on the phytostabilization of a highly Cd (cadmium), …
Results of this study indicated that there is no considerable difference between the predicted log activity values of fresh fly ash materials and aged fly ash materials. 6. Conclusions. Leaching of elements from MSWI fly ashes under different pH conditions were investigated. pH dependent leaching tests at pHs ranging from 2 to 12 …
It was also observed that the 8 wt% fly ash containing samples aged in the open for 120 days showed the ILSS to be 5.83% higher and T g to be 21.95% higher as compared to the unaged GFRP samples without fly ash. FTIR spectra confirm the trend of thermo-mechanical properties. Both optical and scanning electron microscopy of the …
A large difference in Pb leaching was observed: the cumulative leaching amount of GT fly ash (707.59–3072.36 mg/kg) was an order of magnitude higher than that of CFB fly ash (22.47–407.314 mg ...
The significant production of municipal solid waste incineration fly ash (MSWI FA) underscores the importance of developing efficient solidification materials. This study employed MgO and CaO for immobilizing MSWI FA (with a 70% fly ash incorporation), and the immobilization effect was compared with that of Portland cement (PC).
Coal fly ash is a fine silt of spherical powdery particles with diameters ranging from less than 0.1 µm to over 100 µm. 5–7 The average size range of the respirable fraction of fly ash is from 1.98 µm to 5.64 µm. 8 Although fly ash is mainly composed of silicon, aluminium, iron, calcium and oxygen, trace elements such as arsenic, chromium ...
The pozzolanic activity of fly ash is defined in terms of the reactions of its main components; SiO2 and A1203 with Ca(OH)2 to form CSH and ... (SOD), catalase (), vitamin A, and vitamin E status. We observed 102 participants aged 35–66 years from Sung Neon, Nakhon Ratchasima, Thailand. The blood samples were collected to measure the …
Characterization of naturally aged cement-solidified MSWI fly ash. Du B 1, Li J 1, Fang W 1, Liu Y 1, Yu S 1, Li Y 1, Liu J 1 Author information ... (S/S) is the most common treatment for municipal solid waste incineration fly ash (MSWI-FA), and is widely applied in developed countries but has a history barely longer than 10 years in ...
The dissolution and release of active ions, such as Si 4+, Al 3+ and Ca 2+, from fly ash directly affect the rate and extent of reaction product formation, which in turn affect the physical and mechanical properties of fly ash filling materials.In this study, low-calcium fly ash was soaked and activated in NaOH solutions with different …
The nitric acid aging process, which can occur in the atmosphere, leads to a 200–600% increase in oxidative potential, as measured by cellular and acellular assays. This laboratory study demonstrates that the toxic effects of aged versus freshly emitted …
Fly ash amendment at the right amounts can enhance some of the physicochemical and biological properties of soils (Singh et al., 2016). In a sodic soil, application at 20t ha −1 increased the ...
1. Introduction. To reduce CO 2 emissions from modern cement industry, supplementary cementitious materials (SCMs) have been widely used to replace partial of Portland cement or cement clinker and prepare blended cement. Thus, a large number of industrial solid wastes and some natural resources have been selected and processed …
Rice husk ash (RHA) is classified as a highly reactive pozzolan. It has a very high silica content similar to that of silica fume (SF). Using less-expensive and locally available RHA as a mineral admixture in concrete brings ample benefits to the costs, the technical properties of concrete as well as to the environment. An experimental study of …
Strength activity index (SAI) was based on the compressive strength test performed on mortar cube specimen which were cast by partial replacement of cement with bagasse ash and fly ash at 10, 20 ...
Fly ash-based geopolymer mortar (GFM) was used as an adsorbent material to methylene blue () and also the dye removal material using the photocatalytic mechanism. The GFM, containing 50 wt% river sand aggregate, was prepared to have approximately 46% open porosity, pore size distribution between 0.01 and 3.5 mm, and …
1. Introduction. Fly ash is a major by-product of coal-fired power generation. Coal consumption has led to an increase in fly ash emissions along with the development of industry and urbanization [1], [2].Globally, coal-fired power stations discharge over 500 million tons of FA annually [3], [4].Storing of FA in stockpiles consumes substantial land …
