Coal ash fusion temperature (AFT) is one important parameter for coalfired boiler design and evaluation in a power plant. The relationship between coal AFT and the chemical composition of coal ash is rather complex in nature and makes the modeling of AFT difficult. In this work, a leastsquares support vector machine (LSSVM) model, which was based on a dynamically optimized search technique ...
WhatsApp: +86 18203695377Sintering related temperatures. Sintering is an important process at the transition of ash to slag, which is predominantly initiated by the neck growth between ash particles and is shown in Fig. 12. Sintering of coal ash is a result of phases transformation in solid and liquid states.
WhatsApp: +86 18203695377The combination of K2O and Na2O may enhance the flux efficiency. In this work, the effect of K2O/Na2O mass ratio on fusion behavior of coal ash with high silicon and alumina level was evaluated by ...
WhatsApp: +86 18203695377the ash composition and its relation with AFT indicates Sialoferric nature of these coals. The corre ... coal industry. The AFT partially reflects the extent of ash agglomeration during coal conversion,, combustion, gasification, liquefaction, ... the process, the initial deformation temperature (IDT),hemisphericaltemperature(HT ...
WhatsApp: +86 18203695377There are many types of specifications used to describe coal, these. include: Geological location, basin, seam, and rank. Physical heating value, size, moisture, ash, HGI, ash fusion temp. Chemical sulfur, ash chemistry, ultimate and trace elements. The key to the use of these specifications is to understand the.
WhatsApp: +86 18203695377Coal is a solid, black, readily combustible fossil fuel that contains a large amount of carbonbased material approximately 50% of its weight. The formation of coal takes a significant amount of time (on the order of a few million years), and the first coalbearing rock units appeared about 290360 million years ago, at a time known as the Carboniferous or "coalbearing" Period.
WhatsApp: +86 18203695377Song et al. reported that the AFT decreases with increasing CaO up to the concentration of 30%, above which increasing the CaO leads to an increase in the AFT. The result was attributed to the subliquidus phase transformation from anorthite to the gehlenite phase, increasing CaO by over 30%. ... The pyrolysis process of coal/biomass generally ...
WhatsApp: +86 18203695377Coal gasification fine slag (FS), a kind of byproduct of coal chemical industry, was recovered for the preparation of functional adsorbents by acid leaching process, which was orthogonally optimized by HCl, HNO3, HF, HAc, and H2SO4. Methylene blue () was used to evaluate the performance of functional adsorbents. The results demonstrated that % of the leaching efficiency (RLE) and ...
WhatsApp: +86 18203695377the formation of slaglayer protection during the process of lowAFT coal EFB gasification, and it might abate the generations of fouling and Analytical methods deposition on the tube surface in subsequent operation unit (, superheater) [44]. Thus, it might be anticipated that the additions of CS or The ...
WhatsApp: +86 18203695377Blending is a promising method to modify the ashfusion characteristics of coal to meet gasification requirements. To investigate the variation in ashfusion behavior for high ashfusiontemperature (AFT) coal through coal blending and its regulating mechanism, the ashchemistry characteristics of four coals (Nantun, Pengzhuang, Biaodian, and Xiangyuan) were analyzed.
WhatsApp: +86 18203695377Materials. Huainan (HN) coal from Huainan coalmining area in China was selected in this work to be representative of AFT coals. Table 1 gives the characterization of HN coal, in which the proximate, ultimate analysis of the tested coal was conducted according to the Chinese standards GB/T, GB/T, GB/T, GB/T, GB/T and GB/T .
WhatsApp: +86 18203695377The sintering and slagging of coal ash in the combustion chamber is mainly influenced by the melting point or ash fusion temperature (AFT) and the chemical contents of coal (Shi et al. 2021). The ...
WhatsApp: +86 18203695377The coal combustion testing process was carried out at the Powder Coal Combustion facilities at National Research and Innovation ... with low ash and sulfur content. EFB, FRD, and coal have an ash content of %, %, and %, respectively. AFT values for coal, EFB, and blends are pretty lower than FRD and satisfy the minimum limit ...
WhatsApp: +86 18203695377To establish a simple method predicting ash fusion temperature (AFT) using FactSage calculation, the deformation temperature (DT) or flow temperature (FT) of coal ashes were measured by AFT analyzer and ash compositions were measured by Xray fluorescence spectrometry. The method to predict the DT and FT was proposed based on the liquidphase content and its variation trend with increasing ...
WhatsApp: +86 18203695377The slagliquid transformation temperature or AFT is the highest at the point where Al 2 O 3 is a maximum, which is the point in the bottom left corner of Fig. AFT at that point is >1900 ° a twodimensional area where Al 2 O 3 is kept fixed at any point, the AFT in the levels between SiO 2 and TiO 2 are almost the same. The above result is in agreement with the results found on ...
WhatsApp: +86 18203695377The cogasification of coal and biomass is of importance for coal clean conversion and biomass utilization on a large scale. To investigate the effecting behaviors of biomass on ash fusion characteristics of low ashfusiontemperature (AFT) coal, the ash chemical properties of three materials (Shenmu coal (SM), chestnut shell (CS), and rice husk (RH)), the variations in SM mixed AFT with ...
WhatsApp: +86 18203695377The adiabatic flame temperature (AFT) is defined as the temperature attained when all of the chemical reaction heat released heats combustion products. In practical coal combustion systems, excess oxygen is usually applied to achieve complete coal burnout. In this chapter we set O 2 concentration in the flue gas at % v/v. AFT in pure oxygen ...
WhatsApp: +86 18203695377Considering that the process of AFT regulation is usually needed in an industrial gasifier when the AFT of coal is higher than 1500 °C and to verify whether the correlation was not only available for raw coal but also for AFT regulation (coal blending, flux), the lowAFT ZL, flux (CaO and Fe 2 O 3) with a certain mass ratio were added to the ...
WhatsApp: +86 18203695377Gasification of coal is a process whereby coal is converted to a syngas, which is predominately a mixture of carbon monoxide and hydrogen. ... The AFT is a common analysis performed on a coal sample as part of its routine characterization and can be a useful indicator of the general suitability of a specific coal for entrainedflow gasification ...
WhatsApp: +86 18203695377The United Mine Workers of America (UMWA) formed in 1890 to fight for better pay and working conditions for the nation's coal miners. In Colorado the union was most active in the early twentieth century, with thousands of members joining strikes in the southern coalfields of Fremont, Huerfano, and Las Animas Counties. In the spring of 1913, the UMWA led a strike there that resulted in the ...
WhatsApp: +86 18203695377Effect of coal nature on the gasification process. Mustafa Ozer, ... Badie Morsi, in Integrated Gasification Combined Cycle (IGCC) Technologies, 2017. Ash fusion temperature (melting temperature). AFT is an indicator of the ash melting behavior in the gasification process (Li, 2010).For the gasification of lowrank coals, such as lignite and brown coal, in fixed and fluidized beds ...
WhatsApp: +86 18203695377To investigate the variation in ashfusion behavior for high ashfusiontemperature (AFT) coal through coal blending and its regulating mechanism, the ashchemistry characteristics of four coals ...
WhatsApp: +86 18203695377Fig. 1 shows the neutralizing capacity of coals and coalashes. All twelve lignites (Samples 112, Table 1) required l 1 M H 2 SO 4 per kg coal, to establish a stable pH at liquid to solid ratio 10:1. The only asphaltite, Sample 13, used l/kg, mainly due to the high 'ash' percentage. We use a selected range of particle sizes, μm.
WhatsApp: +86 18203695377Mining is a process that is known to have a tremendous effect on both the land that the mine is contained within and the surrounding areas. Two of the most common mining processes are those of underground mining and strip mining. Underground mining is known to cause a variety of things to take place, during the mining process. As a mining ...
WhatsApp: +86 18203695377There exists a number of studies, demonstrating that the chemical and mineral composition of the coal ash governs its melting characteristics and fusion temperatures (Gray 1987; Kucukbayrak et al. 1993; Vorres 1979; Vassilev et al. 1995; Winegartner and Rhodes 1975).Since the composition of the ash influences the AFT magnitudes and, thereby, performance of a coalbased process, it is essential ...
WhatsApp: +86 18203695377The coal formation process involves the burial of peat, which is made of partly decayed plant materials, deep underground. The heat and pressure of burial alters the texture and increases the carbon content of the peat, which transforms it into coal, a type of sedimentary rock. This process takes millions of years. Types, or "ranks," of coal are determined by carbon content. There are four ...
WhatsApp: +86 18203695377Method Mechanically Activated Coal Gangue and Fineness Detection (1) Mechanically activated coal gangue Coal gangue will produce varying particle sizes depending on the machine grinding instruments used, resulting in diverse mineral crystals, giving the particles activity. Therefore, the machine grinding process of coal gangue is particularly vital, and the grinding steps in this ...
WhatsApp: +86 18203695377Although a lot of documents indicated that sewage sludge could obviously change the AFT of coal in the process of thermal utilization. The articles that adding industrial sludge to change the AFTs of high AFT (FT > 1380 °C) coal for EFB gasification were rare and the corresponding regulation mechanism was imperfect. In this paper, the ash ...
WhatsApp: +86 18203695377Introduction. Coal is used as main feedstock for South Africa's unique synfuels and petrochemicals industry. It is used by as a feedstock to produce synthesis gas (CO+H 2) via the Lurgi fixed bed dry bottom (FBDB) gasification plant located in Secunda gasify >30. million tons of bituminous coal to synthesis gas per year, which is converted to fuels and chemicals ...
WhatsApp: +86 18203695377Although the standard AFT analysis is currently used as prediction tool for AFT of coal, literature studies [1] have shown that this may not represent the actual flow temperature of certain minerals and mineral phases. For example iron (Fe) as Fe 2+ can react with other ash forming constituents leading to the formation of liquid phases at temperatures as low as 700 °C.
WhatsApp: +86 18203695377Ash fusion temperature (AFT) is an important index for coal gasification. A blend of fluxing agent with coal can decrease the AFT to meet the requirements of specific gasification process. Effect of alkaline oxide and silica alumina ratio on decreasing AFT is focused in this study. Simulation ash was used to investigate the effect of alkaline oxide on AFT. The experimental results showed that ...
WhatsApp: +86 18203695377Accordingly, this study presents computational intelligence (CI) based nonlinear models to predict the four AFTs using the oxide composition of the coal ash as the model input. The CI methods used ...
WhatsApp: +86 18203695377She will also speak at the SuperPollutants Summit, attend the Coal Transition Accelerator (CTA) ... Commissioner for Climate Action Wopke Hoekstra will lead the EU negotiating team in the formal decisionmaking process of COP28, including the first Global Stock take under the Paris Agreement. This will be a moment for all Parties to examine ...
WhatsApp: +86 18203695377The AFT of coal after leaching increased to >1600 ... This is indeed what happened with the coal within the gasification process when Fecontaining minerals are transformed. This implies that the threecomponent system Al 2 O 3 FeO x SiO 2 is not one of the critical phase formations affecting ash fusion temperature in the blend. However ...
WhatsApp: +86 18203695377The differences between K and M coal are also found in AFT under reducing conditions and ash analysis. AFT under reducing conditions of M coal is very low with deformation temperature (DT), softening temperature (ST), hemispherical temperature (HT), and fluid temperature (FT) of 1090, 1090, 1120, and 1140 °C, respectively.
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