Mineralogical Studies of Coal Fly Ash for Soil Application in Agriculture

Abstract

Coal fly ash procured from Guru Gobind Singh Super Thermal Power Plant, Ropar, Punjab, India, was analyzed for its mineralogical content and thermal stability by x-ray diffraction (XRD), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and physicochemical properties. XRD studies showed that major crystalline phases observed were quartz (SiO 2 ) and aluminum silicon oxide (Al 4.52 Si 1 . 48 ) with macro-and microelement (N, P, K, Mg, Zn, S, and Fe). Fly ash showed thermal stability up to 500 C and reduction in weight was up to 200 C, primarily due to loss of water and decarboxylation as revealed by TGA plots. FTIR of fly ash showed that the most prominent peaks in the spectra corresponded to Si-O and Al-O stretch vibrations. Coarse-grain accumulation of fly ash indicated the presence of 70% of fine-grained particles of 0.075 mm. Coal fly ash was alkaline in nature (pH 7.85 AE 0.03) with an electrical conductivity of 0.14 AE 0.02 mS m À1 , water holding capacity of 62%, low bulk density of 0.99 g cm À3 , and a surface area of 0.96 m 2 g À1 . With properties similar to that of soil coal, fly ash represents a suitable material for use in specific quantities as a soil amending agent in agriculture.

Kerogen Beneficiation from Longkou Oil Shale Using Gravity Separation Method

“…Additionally, the intensity of each peak increased with the increasing of density fractions, it indicated that the higher density fraction of oil shale it was, the higher content of each inorganic mineral in the oil shale sample, and it also indicated there was almost the same mineral composition in six density fractions of oil shale samples. By comparing these patterns we can note that the lower two present peaks with broad base lines, 13,14 typical of kerogen or coal patterns rich in organic matter and low inorganic mineral matter, whereas the upper four presented well-defined peaks in according with its high inorganic mineral matter content. 3.4.…”

Minimisation of environmental effects related with storing fly ash from combustion of hard coal

“…In the subsequent series, bentonite was added to the granulate (tests Nos. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19], and in the tests Nos. 14-19 waterglass (R140 CAS: 1344-09-8) was used as the binding liquid.…”

“…1, 2) and at the bottom of the deposit (tests Nos. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Binding liquid flow rate Q was 0.83 m 3 /s (test No.…”

“…1) and 1.25 m 3 /s (tests Nos. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Granulator disk angle of inclination was equal to 35°.…”

“…The addition of fly ashes improves the mechanical characteristics of concretes and mortars as a consequence of their pozzolanic activity and the spherical form of their particles [13]. The use of coal fly ash for soil amelioration may provide soil enrichment [14]. In some cases, depending on the composition of the original waste, the combustion conditions and the combustion technology adopted bottom ash may also exhibit pozzolanic activity as a consequence of high contents of amorphous phase.…”