of Hazardous Trace Elements (HTEs) into the environment is influenced by both natural and anthrop... more of Hazardous Trace Elements (HTEs) into the environment is influenced by both natural and anthropogenic activities. In the present study, chemometric analysis is applied as a tool to evaluate the release behaviour of Hazardous Trace Elements (HTEs) during coal mining and utilization processes. Statistical tools like Principal Component Analysis (PCA), cluster analysis, and Linear Discriminant Analysis (LDA) were applied on the TE concentrations of raw coals and thermally treated coals. PCA and LDA successfully predicted the association of potentially hazardous elements contained in coal and their release behaviour. Consistency of chemometric results with the experimental results indicates that it can be used for analyzing release behaviour of HTEs during mining and utilization.
Northeast Indian coals have immense potential for energy, power and other value added products. I... more Northeast Indian coals have immense potential for energy, power and other value added products. In comparison to the country’s total deposit, the reserve though less, deserves attention owing to different physico-chemical characteristics and non-availability of good quality coal in the country. The state of Nagaland forms a part of the northern extension of the Arakan-Yoma range which has undergone orogenic upheavals during the Cretaceous and Tertiary period. The state has a good deposit of high sulfur coals, lying unexploited industrially so far. In the present investigation, a systematic study on Nagaland coals has been done to explore their suitability as a source of energy. Coal samples from different coalfields have been analyzed for proximate, ultimate, TGA, composition of ash, and petrographic constituents. The swelling and caking indices have been determined. The fouling and slagging indices of these coals have also been reported. The Nagaland coals have high sulfur content similar to those of the other tertiary coals and low ash fusion temperature range, for which they are not suitable for the power generation with the conventional combustion systems, however could be suitable for combustion with FBC techniques, which operate at lower temperature (≤ 850°C) with in-situ desulphurization mechanism. These coals also show characteristics of non-caking and swelling in general.
ABSTRACT tIn the present investigation, the effect of biochar incorporation into high sulphur min... more ABSTRACT tIn the present investigation, the effect of biochar incorporation into high sulphur mine rejects on bufferingof the acid production was assessed. For this, kinetic experiments on pure mine rejects (LMR) and biocharamended mine rejects (LMRBC) were performed for 720 h. Leachate samples were collected at 0, 20, 40,60, 168, 336, 504 and 720 h and characterized. Results revealed that incorporation of biochar inhibitedthe acid production rate (from 10.4 kg/Mt/h to 3.81 kg/Mt/h) and enhanced the alkali consumption (from9.7 kg/Mt/h to 13.9 kg/Mt/h). Biochar was capable to neutralize all the acid produced. As a neutralizingagent, Mg2+dominated over Ca2+. The efficiency of biochar to reduce the rate of acid production may bedue to either the reduction in Fe3+concentration or production of reduced sulphur compounds in reducingconditions of biochar. This is also supported by molar sulphur to iron ratio of leachate water. Principalcomponent analysis applied on the data revealed that biochar altered the salt and carbon dissolutionprocesses of mine rejects. It inhibits the acid production and accelerates the alkali releasing.
Journal of the Geological Society of India, Sep 1, 2015
Six high sulphur coal samples along with two fly ash samples were characterized by using X-ray di... more Six high sulphur coal samples along with two fly ash samples were characterized by using X-ray diffraction (XRD), Energy Dispersive x-ray Fluorescence (EDXRF), Atomic Absorption Spectroscopy (AAS), Fourier Transform Infrared (FT-IR) and Scanning Electron Spectroscopy (SEM) techniques to interpret their mineral matters and inorganic constituents. The proximate, ultimate and sulfur analyses of the coal and fly ash samples were also performed to know their possible aspects of utilization. Significant amount of silicate/clay minerals along with other elements are found to be present in these coals and fly ash samples. The SEM micrographs showed the presence of pyrite and marcasite in different forms including clusters of pyrites in the coals. The leaching characteristics of the coal and fly ash samples showed the mobilization of some potentially hazardous elements (PHEs) from them. Mercury was found to be leached out with ~0.50 ppm from fly ash samples in water.
The preparation of some oxides and mixed oxide sorbents with aluminosilicate type of binders for ... more The preparation of some oxides and mixed oxide sorbents with aluminosilicate type of binders for high temperature desulphurisation of fuel gases is di scussed. The sorbents investigated are extrudates of ZnO, Indian iron-ore fm es and slimes, ZnO-iron ore fines , ZnO-iron ore slimes, CuO-iron ore slimes, combusted coal ashes (CCA), CuO-CCAs, Zn0-Fe20 3 , Cu0Fe203 and CuO-Fe20 r A1 20 3. These sorbents have been found highly efficient in absorbing sulphurous gases . The fresh, sulphidised, regenerated sorbents of mixed metal oxides and their chemical ph ases have been identified by X-ray diffracti on technique. The presence of x-chalcopyrite, ZnS, morihoikite, CuFe2S3 , CuFeS3, Cu3(S04)(0H)4 and CuS04 5H20 in both major and minor phases in th e sulphidised samples indi cate the absorption of sulph r from sulphurous gases at hi gh temperatures. The crushing strength of the fresh, sulphidised, regenerated and resulphidised sorbents has been determined. The performance o f the sorbents ...
International Journal of Coal Science & Technology, 2021
In this research work, isolation of humic acid from coal of Northeastern region of India is repor... more In this research work, isolation of humic acid from coal of Northeastern region of India is reported. The study is also targeted for application of the coal-derived humic acid in acid mine drainage (AMD) water treatment and electrochemical devices. All the obtained results are compared with the standard humic acid and examined the formation of humic acid from the coal. The isolated coal-derived humic acid is found to be high degree of humifications and relatively stable up to about 200 °C. The FTIR study indicates the formation of metal-humic acid complexes. On treatment with acidic water (AMD), the coal-derived humic acid was found to have the ability to remove toxic metal such as (in order) Pb > Cu > Zn > Cd. In addition, the preliminary electrochemical properties of the isolated humic acid are also discussed in the paper. The specific capacitance of the isolated coal-derived humic acid via cyclic voltammetry and charge-discharge analysis is found to be 7 mF/g at scan rat...
of Hazardous Trace Elements (HTEs) into the environment is influenced by both natural and anthrop... more of Hazardous Trace Elements (HTEs) into the environment is influenced by both natural and anthropogenic activities. In the present study, chemometric analysis is applied as a tool to evaluate the release behaviour of Hazardous Trace Elements (HTEs) during coal mining and utilization processes. Statistical tools like Principal Component Analysis (PCA), cluster analysis, and Linear Discriminant Analysis (LDA) were applied on the TE concentrations of raw coals and thermally treated coals. PCA and LDA successfully predicted the association of potentially hazardous elements contained in coal and their release behaviour. Consistency of chemometric results with the experimental results indicates that it can be used for analyzing release behaviour of HTEs during mining and utilization.
Northeast Indian coals have immense potential for energy, power and other value added products. I... more Northeast Indian coals have immense potential for energy, power and other value added products. In comparison to the country’s total deposit, the reserve though less, deserves attention owing to different physico-chemical characteristics and non-availability of good quality coal in the country. The state of Nagaland forms a part of the northern extension of the Arakan-Yoma range which has undergone orogenic upheavals during the Cretaceous and Tertiary period. The state has a good deposit of high sulfur coals, lying unexploited industrially so far. In the present investigation, a systematic study on Nagaland coals has been done to explore their suitability as a source of energy. Coal samples from different coalfields have been analyzed for proximate, ultimate, TGA, composition of ash, and petrographic constituents. The swelling and caking indices have been determined. The fouling and slagging indices of these coals have also been reported. The Nagaland coals have high sulfur content similar to those of the other tertiary coals and low ash fusion temperature range, for which they are not suitable for the power generation with the conventional combustion systems, however could be suitable for combustion with FBC techniques, which operate at lower temperature (≤ 850°C) with in-situ desulphurization mechanism. These coals also show characteristics of non-caking and swelling in general.
ABSTRACT tIn the present investigation, the effect of biochar incorporation into high sulphur min... more ABSTRACT tIn the present investigation, the effect of biochar incorporation into high sulphur mine rejects on bufferingof the acid production was assessed. For this, kinetic experiments on pure mine rejects (LMR) and biocharamended mine rejects (LMRBC) were performed for 720 h. Leachate samples were collected at 0, 20, 40,60, 168, 336, 504 and 720 h and characterized. Results revealed that incorporation of biochar inhibitedthe acid production rate (from 10.4 kg/Mt/h to 3.81 kg/Mt/h) and enhanced the alkali consumption (from9.7 kg/Mt/h to 13.9 kg/Mt/h). Biochar was capable to neutralize all the acid produced. As a neutralizingagent, Mg2+dominated over Ca2+. The efficiency of biochar to reduce the rate of acid production may bedue to either the reduction in Fe3+concentration or production of reduced sulphur compounds in reducingconditions of biochar. This is also supported by molar sulphur to iron ratio of leachate water. Principalcomponent analysis applied on the data revealed that biochar altered the salt and carbon dissolutionprocesses of mine rejects. It inhibits the acid production and accelerates the alkali releasing.
Journal of the Geological Society of India, Sep 1, 2015
Six high sulphur coal samples along with two fly ash samples were characterized by using X-ray di... more Six high sulphur coal samples along with two fly ash samples were characterized by using X-ray diffraction (XRD), Energy Dispersive x-ray Fluorescence (EDXRF), Atomic Absorption Spectroscopy (AAS), Fourier Transform Infrared (FT-IR) and Scanning Electron Spectroscopy (SEM) techniques to interpret their mineral matters and inorganic constituents. The proximate, ultimate and sulfur analyses of the coal and fly ash samples were also performed to know their possible aspects of utilization. Significant amount of silicate/clay minerals along with other elements are found to be present in these coals and fly ash samples. The SEM micrographs showed the presence of pyrite and marcasite in different forms including clusters of pyrites in the coals. The leaching characteristics of the coal and fly ash samples showed the mobilization of some potentially hazardous elements (PHEs) from them. Mercury was found to be leached out with ~0.50 ppm from fly ash samples in water.
The preparation of some oxides and mixed oxide sorbents with aluminosilicate type of binders for ... more The preparation of some oxides and mixed oxide sorbents with aluminosilicate type of binders for high temperature desulphurisation of fuel gases is di scussed. The sorbents investigated are extrudates of ZnO, Indian iron-ore fm es and slimes, ZnO-iron ore fines , ZnO-iron ore slimes, CuO-iron ore slimes, combusted coal ashes (CCA), CuO-CCAs, Zn0-Fe20 3 , Cu0Fe203 and CuO-Fe20 r A1 20 3. These sorbents have been found highly efficient in absorbing sulphurous gases . The fresh, sulphidised, regenerated sorbents of mixed metal oxides and their chemical ph ases have been identified by X-ray diffracti on technique. The presence of x-chalcopyrite, ZnS, morihoikite, CuFe2S3 , CuFeS3, Cu3(S04)(0H)4 and CuS04 5H20 in both major and minor phases in th e sulphidised samples indi cate the absorption of sulph r from sulphurous gases at hi gh temperatures. The crushing strength of the fresh, sulphidised, regenerated and resulphidised sorbents has been determined. The performance o f the sorbents ...
International Journal of Coal Science & Technology, 2021
In this research work, isolation of humic acid from coal of Northeastern region of India is repor... more In this research work, isolation of humic acid from coal of Northeastern region of India is reported. The study is also targeted for application of the coal-derived humic acid in acid mine drainage (AMD) water treatment and electrochemical devices. All the obtained results are compared with the standard humic acid and examined the formation of humic acid from the coal. The isolated coal-derived humic acid is found to be high degree of humifications and relatively stable up to about 200 °C. The FTIR study indicates the formation of metal-humic acid complexes. On treatment with acidic water (AMD), the coal-derived humic acid was found to have the ability to remove toxic metal such as (in order) Pb > Cu > Zn > Cd. In addition, the preliminary electrochemical properties of the isolated humic acid are also discussed in the paper. The specific capacitance of the isolated coal-derived humic acid via cyclic voltammetry and charge-discharge analysis is found to be 7 mF/g at scan rat...
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