IR@CIMFR - Central Institute of Mining and Fuel Research (CSIR)
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Study Research Protocol for Phenome India-CSIR Health Cohort Knowledgebase (PI-CHeCK): A Prospective multi-modal follow-up study on a nationwide employee cohort
No full textComparative assessment of the soil restoration process by four abundant tree species in a humid subtropical post-mining area
No full textFast weathering of post-mining soil in humid subtropical regions results in nutrient depletion, acidification, erosion, reduced
water retention, impaired carbon sequestration, and disrupted ecosystem services. This study highlights how the selection of
tree species plays a crucial role in influencing the quality of post-mining soil, which is essential for successful eco-restoration
efforts. The comparison between native (Azadirachta indica and Dalbergia sissoo) and fast-growing non-native tree species
(Acacia auriculiformis and Senna siamea) and their impact on soil properties in a reclaimed post-mining site of Eastern India
was assessed. After 8 years, S. siamea and A. auriculiformis showed superior growth compared to A. indica and D. sissoo. Soil
parameters like microbial biomass, organic carbon, electrical conductivity, dehydrogenase activity, fluorescence diacetate
hydrolase activity, soil basal respiration, total nitrogen, available phosphorus (P), sulfur (S), and calcium are highly responsive
and can effectively indicate the recovery of post-mining soil. Large-scale planting of S. siamea and A. auriculiformis might lead
to environmental issues due to P and S leaching. In contrast, native species like A. indica and D. sissoo showed moderate
improvement in the sensitive soil indicators. This study emphasizes the significance of choosing suitable native tree species
for the restoration of post-mining soils in humid subtropical regions.
Interfacial engineering of CuSe2/FeSe2 heterojunctions for water splitting: a pathway to high-performance hydrogen and oxygen evolution reactions
No full textThe efficiency of green hydrogen production via water electrolysis is critically constrained by high energy
barriers, particularly during the oxygen evolution reaction (OER). In this study, CuSe2 /FeSe2 heterojunctions are introduced as cost-effective and highly active bifunctional electrocatalysts for overall water split-
ting. Leveraging the abundant and tunable properties of Cu- and Fe-based chalcogenides, this work
demonstrates how charge redistribution and interfacial electronic coupling in the heterostructure significantly enhance catalytic activity. High surface area CuSe2/FeSe2 heterojunctions enhance hydrogen and
oxygen adsorption and accelerate charge transfer, achieving low overpotentials (666 mV for the HER and
490 mV for the OER at 10 mA cm−2 ), a high OER current density (135 mA cm−2), and a reduced Tafel
slope (137 mV dec−1). The catalyst maintained stable performance over 24 hours of continuous operation
at 10 mA cm−2 , confirming its structural robustness and practical viability. These findings position CuSe2/
FeSe2 heterojunctions as promising candidates for scalable, sustainable hydrogen production and
advanced electrochemical energy technologie
Environmental and Health Impacts of Uranium Mining in Jadugoda, Jharkhand
No full textT
he uranium mines in Jadugo
da and the surrounding areas
of the Singhbhum thrust belt in
Jharkhand State are currently active
mines in India. These mines play
a crucial role in providing fuel to
nuclear power plants. From 1968,
Uranium Corporation of India
Limited (UCIL) began its uranium
mining and processing operations
in Jadugoda, that is predominantly
inhabited by tribal communities.
Radiation exposure resulting from
uranium mining and processing
in Jadugoda, has been a concern
for the last two decades. Organiza
tions such as 'Jharkhandi Organi
zation against Radiation' (JOAR)
were founded in Jadugoda and be
gan to protest and accuse UCIL of
neglecting public health concerns.
T
hey have discovered information
about individuals experiencing
physical deformities, tuberculosis,
cancer, and previously uniden
tified illnesses occurring among
the population in and around the
uranium plant. These symptoms
were attributed to the effects of ra
diation. Tailing ponds also causes a
substantial release of harmful gases
and nuclear radiation, resulting in
the pollution of water, vegetation,
soil, and ultimately, the food chain.
T
his article provides a concise
overview of the uranium mining,
ore processing, and waste manage
ment operations in jadugoda.
Keywords: Uranium mines, Jadu goda, Radiation, exposure, Tailing
pond
Modification of Functional Groups and Stacking Structure of Some Indian Non-Coking Coals During Pyrolysis
No full textChanges in stacking structure and the functional groups of three non-coking coals during pyrolysis have been carried out using X-ray diffraction (XRD) and Fourier-Transform Infrared Spectroscopy (FTIR). The interlayer spacing of the stacking structure changed from 3.44 to 3.66 Å, 3.49 to 3.68 Å, and 3.60 to 3.72 Å and aromaticity changed from 0.64 to 0.70, 0.63 to 0.74, and 0.68 to 0.78 due to pyrolysis of the samples AMD, BMD and JMD respectively. The rank parameters also change from 1.80 to 2.29, 1.72 to 2.36, and 1.61 to 3.49 for the same coals in similar order. It is observed that the interlayer spacing, aromaticity and rank of coal increase with the increase in temperature. The FTIR results show that the functional group associated with minerals increases while the functional groups associated with coal macerals like methyl group, C=C aromatic, and oxygen-containing functional groups decrease due to pyrolysis. The FTIR structural parameters such as the ratio of aliphatic to the total atomic hydrogen, and the ratio of carbonyl to aromatic groups decrease with the increase in temperature while aromaticity, degree of condensation of aromatic rings, and the ratio of aliphatic to aromatic carbon increase with the increase in temperature up to 600°C. The sudden changes in FTIR structural parameters of coals are observed at 800°C. The present study shows that with increasing temperature, the aromatization and degree of condensation of aromatic rings of coal increase with the removal of aliphatic side chains and reduction in oxygen-containing functional groups
Analytical and Numerical Modeling Approaches for Estimating the Optimum Line of Extraction in Continuous Miner Workings with Field Observations
No full textThe line of extraction in Bord and Pillar (B&P) or Room and Pillar methods plays a paramount role in the extraction of coal pillars in underground mines. It is an important factor that has to be decided at the premining stage, and its optimization not only boosts productivity but also enhances the stability of underground operations. In Indian coal mines or in other B&P mines around the world, the quest to determine the effective line of extraction remains elusive. In Indian B&P coal mines, both diagonal and straight lines of extraction have been widely adopted. In one of such mines, Mine-A, situated in the southern part of India, several coal panels were successfully extracted in the middle seam using a continuous miner (CM) technology in straight and diagonal lines of extraction. However, local geomining effects, such as the influences of top seam panel goaves, barrier pillars, delays in main fall, surges in abutment loading, and increased convergence in roadways caused difficulties throughout the coal extraction in some panels of the middle seam CM workings. This underscores the need to evaluate the optimum line of extraction for successful pillar extraction in B&P workings. Hence, a study was undertaken with numerical modeling and extensive field observations. Strata monitoring instruments such as stress cells, rotary telltale, auto warning telltale, and 4-anchor extensometers were extensively utilized in the field to observe the stress distribution and roof displacement in both lines of extraction. Comparative analysis using field data and numerical modeling with FLAC3D (version 5.0) exhibited that in the diagonal line of extraction, incidents such as delays in major and main fall occurrences, surge in induced stress distribution, and increased rock load development were more prevalent than in the straight line of extraction. This analysis unequivocally demonstrated that a straight line of extraction offers better safety and more effectively reduces ground instabilities in CM panels. Furthermore, the principles of plate theory were used to interpret the roof deflection during the depillaring of the panels, and the modeling results were corroborated with these theoretical findings
Investigating Pore Characteristics and Their Dependence on Shale Composition: Case Study from a Permian Basin in India
No full textShale reservoirs, often acting as caprocks for conventional hydrocarbon reservoirs, exhibit moderate to high porosity and remarkably low permeability. Organic-rich shales serve as reservoirs for unconventional hydrocarbons. This study focused on evaluating the characteristics of the source rocks and the factors influencing pore parameters in organic-rich shale from a Permian Basin in India, exploring its feasibility as both a CO2 sink and a natural gas source. Experimental techniques were employed to explore the mineral and the organic matter characteristics along with attributes of the pores hosted within them. The investigated shales displayed diverse thermal maturity levels, spanning from that in oil-prone to gas-prone zones, with the total organic carbon content varying from 0.72 to 24.98 wt %, indicating substantial organic richness. Rock-Eval pyrolysis results revealed a range of thermal maturity (Tmax) values between 426 and 474 °C, while X-ray diffraction analysis indicated significant quantities of illite and kaolinite, along with trace amounts of pyrite in certain samples. Field-emission scanning electron microscopy imaging and its detailed interpretation provided valuable insights into the pore structure and arrangement. In our study, we found that both the clay content and the organic matter significantly contribute to gas adsorption. While clay content strongly influences mesopore attributes, the organic matter predominantly affects micropore attributes. Furthermore, a direct relationship among fractal dimension, surface area, and pore volume, indicating increased complexities with these variables. Our examination of mesopore fractal attributes revealed that smaller mesopores exhibit a more convoluted and irregular configuration in comparison to the larger ones. These findings provide significant insights into the pore morphology of the analyzed shale sample
Influence of lithological contrast on elastic anisotropy of shales under true-triaxial stress and thermal conditions
No full textThe intrinsic anisotropy of shales, arising from their complex microstructure, including mineral alignment and bedding orientation, significantly influences seismic wave propagation, impacting subsurface imaging and reservoir characterization. Despite extensive research on shale anisotropy, studies employing cubic specimens under true-triaxial conditions, which provide a more realistic simulation of subsurface stress states, remain limited. This study investigates the elastic anisotropic behaviour of two distinct shale lithotypes: grey shale (GSH) and silty shale (SSH) from the Permian Barakar Formation of Lower Gondwana in the Jharia Basin, India, under varying isostatic pressures (8 MPa, 12 MPa, 25 MPa, 35 MPa, and 51 MPa) and temperatures (20 °C, 50 °C, 100 °C, 150 °C, and 200 °C) using a polyaxial loading apparatus. Compressional (Vp) and shear wave (Vs) velocities were measured in multiple orientations—parallel, perpendicular, and at 45° to the bedding plane—allowing for a comprehensive evaluation of elastic properties. The results reveal that both Vp and Vs exhibit a noticeable increase with rising isostatic pressure, indicating enhanced stiffness due to the closure of microcracks and pores. Moreover, GSH consistently demonstrated higher wave velocities compared to SSH, attributed to its higher quartz content and mineral alignment, which contributed to reduced shear wave splitting. The analysis of dynamic bulk modulus (K) indicated a consistent increase with pressure for both shale types, with GSH exhibiting a more linear response compared to the non-linear behaviour observed in SSH, influenced by its clay-rich composition. Temperature-induced changes in elastic properties were minimal, with only slight decrease in wave velocities observed at higher temperatures under constant pressure, inferring to the stability of the shale structure. This stability suggests that thermal expansion and mineralogical transformations do not significantly impact the elastic behaviour of these shales within the temperature range of the test. Furthermore, Thomsen anisotropy parameters (ε and γ) exhibited distinct trends under varying pressure and temperature conditions where overall a reduction in anisotropy was observed with increased pressure, reflecting a transition to more isotropic behaviour as pre-existing microcracks closed. The study provides a baseline understanding of variations in elastic properties of two different shale lithotypes to support subsurface resource exploitation strategies, underscoring the significance of employing cubic specimens under true-triaxial conditions to accurately simulate subsurface stress states
Minimum invasive drill-and-blast designs for optimizing pull efficiency and minimizing overbreaks/underbreaks in varying rock masses
No full textIn tunneling and underground projects, the drill-and-blast method is most commonly utilized for rock excavation. It is notable for cost-effectiveness and versatility in achieving different tunnel profiles. Though the technique has advantages, it also has challenges such as overbreak, undercut, and occasional poor advances, which can increase project costs and delays. The outcome of blast results is also associated with the competency of driller in effectively drilling the planned holes. Hence, frequent and substantial modifications in the blast designs to attain good profile and pull can adversely affect the driller's performance, thereby reducing the desired outcome. This article presents a case study of the Sivok-Rangpo tunnels passing through different classes of rock mass (class III–VI). Minimum changes in cut pattern and periphery holes design were incorporated and found efficient in increasing the tunnel advance rate to 90–92 % of the drill hole length. The processes also reduced the overbreak and underbreak considerably
Methodology in early detection of conveyor belt fire in coal transportation
No full textThermal power units are a major source of power generation in India. Belt conveyor is the leading transportation system in a thermal power plant. Belt conveyor fire in a thermal power plant breaks the chain of the transportation system, stops the feeding to the boiler, and often leads to closure of the plant, and thereby impacts the production for several months incurring huge losses. The main aim of this study is to design a model for early detection of belt conveyor fire and its automatic fire suppression system. The proposed model incorporates safety devices and sensors which shall be activated whenever it is necessary. Based on coal characteristics, threshold limit values (TLV) of sensors are defined. Proximate analysis, critical oxidation temperature, fire ladder, and differential scanning calorimetry (DSC) studies were conducted to characterize the five coal samples used in this study collected from Talwandi Sabo Power Ltd. (TSPL), Mansa, Punjab, India. For the coal samples used in this study (with an average moisture content of 7.59 wt %), the average critical oxidation temperature was observed to be 81.3 ⁰C. Further, the fire ladder study indicates that gas sensors like CO and H2 should be installed in the belt conveyor route. Based on laboratory and field investigations an automated model for early detection of fire was proposed which incorporates safety devices, temperature, and gas sensors, and fire suppression mechanisms