Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

S. K. Misra ¹, J. K. Mohanty ¹, B. Nanda ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar - 751013, Orissa, IN

Abstract

Functional groups and mineral matters in Talcher coal have been identified with the help of FTIR. Oxygen bearing functional group mostly hydroxyl is common in bulk as well as different lithotypes. Minerals such as kaolinite, quartz, goethite etc. have been identified from the spectra. The functional groups data have been used to interpret the conditions of formation of the different lithotypes.

Keywords

FTIR, Gondwana, Coal, Talcher, Orissa.

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B. K. Mohapatra ¹, S. K. Misra ¹, R. K. Sahoo ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar 751013, IN

Abstract

This note is aimed at elucidating the relationship between morphology and chemistry of some ferromanganese samples of Central Indian Ocean basin and describing precisely the factors controlling these variations. The samples investigated were dredged from Central Indian Ocean basin at a depth of 4000-5000 m during cruises of SS Fernela (St. F₄ and F₅), SS Scandy Surveyor (St. SS₄, SS₅, SS₆ and SS₈) and RV Sagarkanya (St. SK₈) conducted by the National Institute of Oceanography, Goa. Because of certain restrictions, location of sample details have not been mentioned.

Keywords

Marine Geology, Ferromanganese Nodules, Indian Ocean.

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J. K. Mohanty ¹, S. K. Misra ¹, B. K. Mohapatra ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar - 75 1 013, IN

Abstract

Trace element distribution in bulk coal and lithotypes viz. durain, fusain, clarain and vitrain in two coal seams of two geological formations of Karharbari and Barakar from Talcher coalfield, Orissa is reported and compared with world coal trace element data. Karharbari coal (seam I) contains higher concentrations of As, Ba, Ce, Cr, Th, U and W than Barakar coal (seam II). On the contrary, coal from seam II has high concentrations of Be, Eu, Hf, Mo, Sb, Sc, Sm, and Zn. In both the formations, durain and clarain contain maximum trace elements including REE in appreciable concentration where as vitrain shows least trace constituents. Positive correlation of ash with Ba, Cs, La, Hf, Th, Rb and Sc indicates inorganic affinity of these trace elements. However Sb, As, Cr and Co show negative relation with ash explaining their organic affinilty.

Keywords

Trace Elements in Coal, Barakar, Karharbari, Talcher Coalfield, Orissa.

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S. K. Misra ¹, J. K. Mohanty ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar - 751 013, IN

Abstract

Talcher coal is non coking and high ash type and presently used for thermal power generation, sponge iron making, cement and chemical industry. Coal beneficiation is being carried out by size reduction followed by washing and gravity separation to reduce the ash content and improve other chemical parameters. Poor washability characteristics of Indian coals in general and Talcher coal in particular and presence of high near gravity materials do not support the conventional washing techniques resulting in below expected quality yield. The role of detailed petrographic studies during processing/benificiation needs special attention in order to improve the quality of coal and competitiveness of the product in the open market.

This paper provides general information on petrogmphic findings of coal from different seams presently exposed in Talcher coalfield in terms of lithotype, maceral, mrcrolithotype, mineral matter and rank (vitrinite reflectance). Importance of lithotype, mineral matter and oxidation characteristics of coals with respect to coal preparation /beneficiation and maceral /microlithotypes in combustion has been discussed in detail.

Keywords

Petrography, Non Coking Coal, Utilisation, Talcher Coalfield, Orissa.

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S. C. Nayak ¹, S. K. Misra ², P. Behera ³

Affiliations
1 MA/52, G G P Colony, P 0 Rasulgarh, Bhubaneswar - 751 010, IN
2 Regional Research Laboratory, C S I R , Bhubaneswar - 751 013, IN
3 PG Department of Geology, Utkal University, Vani Vihar, Bhubaneswar 752004, IN

Abstract

No Abstract.

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J. K. Mohanty ¹, S. K. Misra ¹, B. B. Nayak ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar - 751 013, Orissa, IN

Abstract

The extent of vaporisation and subsequent condensation of many trace elements during coal combustion is largely dependent upon the mode of occurrence of the trace elements, besides many other parameters. Mode of occurrence of a few important trace elements in coals from Talcher coalfield representing low and high ash type from Karharbari and Barakar Formations is studied by sequential leaching experiments. It is observed that in both the coal samples, Cr and Mn exhibit more affinity towards organic matrix and/or insoluble oxide phases. Pb and Cd are mostly associated with soluble sulphide and oxide minerals. Co is mostly bonded with silicate phases in the coal samples. No definite mode of occurrence is visualised for Ni from the present study, as it is associated more with the residue indicating its association with either organic matrix or insoluble oxide.

Keywords

Mode of Occurrence, Trace Elements, Leaching, Coal, Talcher Coalfield, Orissa.

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