Jharia Coalfield Research Articles

Detection and delineation of coal mine fire in Jharia coal field, India using geophysical approach: A case study

Coal mine fire is a serious problem in Jharia coal field, India. The coal mine fire can be detected with different techniques such as borehole temperature measurement, thermo-compositional analysis, remote sensing techniques, thermo-graphic measurement and geophysical methods. In this study, various geophysical methods were used to detect the surface and subsurface coal mine fires. Geophysical techniques used in the present study are apparent resistivity, self-potential (SP), magnetic method and thermography. Geophysical anomalies such as low SP value of \(-60\hbox { mV}\), high negative magnetic response and low apparent resistivity value helped us to detect and delineate the fire and non-fire areas laterally as well as depthwise. Furthermore, the thermography survey was carried out in the coal field using thermal imaging camera in order to substantiate the geophysical methods. This integrated approach was found to be more advantageous for the detection and delineation of surface and subsurface fire with respect to use of any specific techniques. Moreover, the level of threat towards the locality, national railway line was also assessed unambiguously using the above techniques. Hence, proper planning and implementation towards the mitigation of hazard can be achieved on the basis of the reported results.

Development a modified crossing point temperature (CPTHR) method to assess spontaneous combustion propensity of coal and its chemo-metric analysis

Spontaneous combustion of Indian coals was investigated using sponcomb rig at University of Nottingham, UK to assess their susceptibility. In the present study authors have used eleven coal samples collected from the Jharia coalfield (JCF), India. Both thermal as well as gas profiles from sponcomb rig were studied critically to develop a modified crossing point temperature to assess the spontaneous combustion propensity of coal. The product of combustion gases (CO, CO2, CH4, and H2) emitted from sponcomb rig within the temperature range between ambient and 300 °C of these coal samples were studied. The initial product of combustion gas i.e. CO followed by H2 indicates propensity towards oxidation of coal in laboratory condition for Jharia coalfield. The temperatures at which CO and H2 releases in the level of 50 ppm (TCO50, TH250), crossing point temperature of coal (CPTCT) (temperature of coal and bath temperature is same) and modified crossing point temperature of coal (CPTHR) (temperature where dT/dt is equal to 2.0 oCmin−1 because heating rate is double of programme temperature 1 oCmin−1) determined from sponcomb rig categorises the coal as per their propensity to spontaneous combustion. The results of these methods have been compared with other standard method i.e. crossing point temperature method – India, which is widely adopted in Indian regulatory bodies to verify the suitability of this method.

Detection of Cavity Using Electrical Resistivity Tomography (ERT) at Patherdih, Jharia Coal Field, Dhanbad, India

Geophysical survey for cavity detection is one of the most common near surface application. The usage of resistivity methods are also very straightforward for the air filled underground voids, which should have theoretically very high resistivity in the ERT image, whereas the water filled cavities have low resistivity in Electrical Resistivity Tomography (ERT) image. Three different geoelectric arrays Wenner, Schlumberger and Dipole-dipole are applied for detecting cavities. The survey results suggest that ERT is a viable geophysical tool for the detection and monitoring of mining voids and other subsurface cavities. The resolution capacity of joint Wenner-Schlumberger, Dipole-dipole array for the detection of cavity is greater than that of the individual one. Using the ERT survey in Patherdih Thana Basti village (Jharia coal field), a number of air filled cavity or water filled mining voids are detected at around 25-30m of below the ground level at different profile distance of 630m profile length along the road that extending S-E to N-W direction.

Effects of thermal maturity on biomarker distributions in Gondwana coals from the Satpura and Damodar Valley Basins, India

Organic geochemistry of Gondwana coals, especially the distribution of molecular fossils or biomarkers, is not well constrained, throughout the world. In this study, we have, therefore, evaluated biomarker signatures along with bulk organic matter and petrographic characteristics in coal samples collected from two Gondwana Basins in India – Satpura Basin (Kanhan coalfield) and Damodar Valley Basin (Jharia coalfield). From both coalfields, the samples were collected from the Lower Permian Barakar Formation, which is one of the major coal bearing strata in India. A significant variation in thermal maturity levels in the samples is indicated by Rock-Eval pyrolysis and petrographic analysis–with the Kanhan samples generally belonging to immature to early-mature stage, while the Jharia samples display characteristics of overmature coals. This variation in the thermal maturity strongly affects the biomarker distributions. Especially, the terpenoids, hopanes and steranes were considerably degraded due to thermal maturation and were below detection limit in the overmature samples. Presence of aliphatic diterpanes, ent-16α(H)-kaurane, 16α(H)-phyllocladane as well as aromatic diterpanes, retene, methylretenes, tetrahydroretene, simonellite and bisnorsimonellite in low maturity samples indicate terrestrial input, possibly, from the primitive conifers. However, the aliphatic and aromatic diterpanes were below detection limit in overmature samples making it difficult to infer their source. Distributions of polycyclic aromatic hydrocarbons (PAHs) are also controlled by thermal maturity levels, as evident from difference in PAH ratios in the low and high maturity samples.

Development of a universal blast-induced ground vibration prediction model for Jharia coalfields

Development of a universal blast-induced ground vibration prediction model for Jharia coalfields

Coalbed methane-produced​ water characteristics and insights from the Jharia coalfield in India

ABSTRACTCoalbed methane (CBM) has emerged as one of India’s important unconventional natural gas sources in the past decade. A number of environmental questions flank the commercial development of CBM and its holistic success, one of which is coproduced water management. Present work aims at assessing the geochemistry of co-produced water samples collected from CBM wells in Jharia coalfield, India. It is found that pH is within accepted limits and the bacterial contamination is minimal. The major ions present in the water samples are sodium and bicarbonate. It is observed that the produced water is generally influenced by a mix of evaporite dissolution and silicate weathering and the samples are oversaturated with respect to calcite and dolomite. Subsequently, an assessment of the energy requirements of membrane-based technologies (such as reverse osmosis and nanofiltration) has been performed. The estimated energy consumption is 0.45–1.40 kWh per cubic meter of water, for differing levels of sodium desired in treated water. Membrane-based methods seem to be effective for treatment of CBM co-produced water, and the selection of membranes can be based on the geochemistry and also the level of treatment desired.

Simulation of CO2 enhanced coalbed methane recovery in Jharia coalfields, India

Coalbed methane production in Jharia coalfield that lies in India's largest coal basin is underway since a few years now; however, no field-trial of CO2 enhanced coalbed methane (ECBM) recovery has been attempted till date. In this study, a detailed assessment of the techno-feasibility of long-term ECBM recovery for a coal block in Jharia coalfield was conducted using finite difference based numerical simulations. This was followed by a detailed comparative analysis with the performance of another key CBM producing block in Raniganj coal field (Vishal et al. [1]). During coupled CO2‒ECBM recovery, a significant enhancement in the amount of production of CH4 resulted due to the injection of CO2. Approximately, 220 Mm3 of CO2 was injected in the coal block and over 62 Mm3 of CH4 was recovered during the period of study. Upon comparison of the studied coal blocks, it can be well inferred that during the major dewatering stage, the rate of CO2 injection in Jharia block was lower as compared to that in the Raniganj coal block. The studied coal adsorb CO2 quickly and within a time span of nearly one year, peak CO2 matrix concentration near the injection well was achieved, indicating high adsorption potential for CO2.

Experimental investigation on effects of particle size, dust concentration and dust-dispersion-air pressure on minimum ignition temperature and combustion process of coal dust clouds in a G-G furnace

The present study investigates the effects of three important parameters, namely, particle size, dust concentration and dust-dispersion-air pressure on Minimum Ignition Temperature (MIT) and explosion process of coal dust cloud using Godbert-Greenwald furnace. The coal sample collected from Jharia Coalfield, India was used for experimentation. The effects of particle size and concentration of coal dust on MIT of coal dust cloud were studied at five different particle size ranges, that is, <38 µm, 38 to <75 µm, 75 to <212 µm, 212 to <425 µm and 425 to <850 µm. However, the effect of dust-dispersion-air pressure was studied only with the initial three finer particle size ranges, because at coarser sizes it was not possible to maintain a dust cloud of sufficient concentration due to high particle settling velocity and the dust cloud became non-explosive beyond dust-dispersion-air pressure of 30–35 kPa, even at ignition temperature of 1000 °C, which is the limiting temperature of the apparatus. The results indicate that MIT of coal dust cloud increases exponentially from 420 to 730 °C with increase in coal dust particle size. MIT was also found to decrease with the coal dust concentration till a stoichiometric concentration was reached, beyond which MIT slightly increased for the three finer particle size ranges. Nevertheless, in the case of the coarser particle size ranges tested, initially a trivial decrease in MIT was observed only up to certain dust concentration, after which, the MIT increased faintly. The results and the underlying mechanism presented are extremely useful, not only in research and advancement of knowledge on the coal dust explosion process, but also in taking necessary measures for preventing coal dust explosions in underground coal mines.

A safe depillaring design for shallow depth of cover with influence of surface ground movements: a study in Jharia Coalfield

Extraction of coal from a shallow depth of cover especially under multi-seam mining condition requires intensive precautions in respect to safe working and impact on surface structures. A detailed geotechnical investigation is imperative for the design of a suitable support system during depillaring operation. A study has been exercised in Maheshpur colliery of Jharia Coalfield to assess the stability between the parting of VIIIA and VIIIB seams through numerical modeling. The support systems have been framed for split galleries, slices, and goaf edges with the help of well-established Central Mining Research Institute-Indian School of Mines rock mass rating (CMRI-ISM RMR) and NGI-Q system. A suitable method of depillaring has been designed keeping in view the safety of surface structures in respect to subsidence.

Relationship in metastasis of coal fire and land use/cover using thermal imagery and support vector machine classifier

The objective of the present study was to delineate temporal and spatial changes in the coal fire and land use/cover within Bastacolla area of Jharia coal field. Studying this variation helped to decipher interconnection among the dynamics of the coal fire and concomitant changes in land use/cover. The detection of coal fires during a span of 14 years along with transitioning land use/cover was cost-effective and enabled planning for management of coal resources and environment. Landsat series of satellite data of 2002, 2009, 2013, and 2016 were processed for generating land surface temperature profiles vis-a-vis classified land use/cover of the study area. A single cut-off temperature was derived for mapping of coal fires using land surface temperature profile from 2002 to 2016. The satellite images were classified using support vector machines, and for depicting land use/cover change, post-classification change detection was done. Classification accuracy obtained was excellent with kappa coefficient ranging from 0.897 for classified image of 2002 to 0.799 for classified image of 2016. Results revealed that coal fires had shifted to the central west part of the area. Furthermore, pockets of coal fire from northern and eastern part of the study area have diminished. OB dumps and coal quarry/coal dump may be attributed towards the spatial change in coal fire while; OB dumps showed connotation with the highest temperature zones. Ground verifications for temperature profiles and coal fires were carried out using thermal camera which enunciated good agreement with results.

Differential distribution of metals in tree tissues growing on reclaimed coal mine overburden dumps, Jharia coal field (India).

Opencast bituminous coal mining invariably generates huge amount of metal-polluted waste rocks (stored as overburden (OB) dumps) and reclaimed by planting fast growing hardy tree species which accumulate metals in their tissues. In the present study, reclaimed OB dumps located in Jharia coal field (Jharkhand, India) were selected to assess the accumulation of selected metals (Pb, Zn, Mn, Cu and Co) in tissues (leaf, stem bark, stem wood, root bark and root wood) of two commonly planted tree species (Acacia auriculiformis A.Cunn. ex Benth. and Melia azedarach L.). In reclaimed mine soil (RMS), the concentrations of pseudo-total and available metals (DTPA-extractable) were found 182-498 and 196-1877% higher, respectively, than control soil (CS). The positive Spearman's correlation coefficients between pseudo-total concentration of Pb and Cu (r = 0.717; p < 0.05), Pb and Co (r = 0.650; p < 0.05), Zn and Mn (0.359), Cu and Co (r = 0.896; p < 0.01) suggested similar sources for Pb-Cu-Co and Mn-Zn. Among the five tree tissues considered, Pb selectively accumulated in root bark, stem bark and leaves; Zn and Mn in leaves; and Cu in root wood and stem wood. These results suggested metal accumulation to be "tissue-specific". The biological indices (BCF, TFleaf, TFstem bark and TFstem wood) indicated variation in metal uptake potential of different tree tissues. The study indicated that A. auriculiformis could be employed for Mn phytoextraction (BCF, TFleaf, TFstem bark and TFstem wood > 1). The applicability of both the trees in Cu phytostabilization (BCF > 1; TFleaf, TFstem bark and TFstem wood < 1) was suggested. The study enhanced knowledge about the selection of tree species for the phytoremediation of coal mine OB dumps and specific tree tissues for monitoring metal pollution.

Coal Fires a major Source of Greenhouse Gases- a forgotten problem.

Coal fires seriously pollute the environment in several states of the world. Today most coal fires are manmade and emerge from illegal or unprofessional mining activities. The most disastrous coal fires of the world currently occur in China and India. In China the program "Great Leap Forward" in the beginning of the 60ties together with inefficient small scale mining are the main reasons of the 750 coal fires in China, where almost 200 Mt of excellent, near surface coal were burned in uncontrolled coal fires. In India disregard of standards with regards to coal fire prevention is the reason of the burning coal fields. The Jharia Coalfield in Jharkhand started burning in 1916 and burns this year for 100 years. General data on the volume of coal, which burns in Indian coal mines are not available. In general, coal fires start as result of unprofessional or illegal mining activities in open pits and uncontrolled, inactive coal mines by self-combustion of coal. Self-combustion is mainly controlled by the grain size of the coals, in other words the smaller the grain size the higher the risk of oxidation and subsequent temperature build-up. Many coal fires burn underground with variable supply of oxygen. Hence, the coal does not burn completely like in power plants, but it smolders in the underground. Emissions from these smoldering fires and an incomplete combustion of the coal create dust and greenhouse gases such as NOX, CO2, CO2 equi., CO and CH4. These emissions pollute the soil, groundwater and the atmosphere. Coal fire experts discuss since years the percentage and the cumulative influence of coal fires on global warming and climate change. Until now the percentage of greenhouse gases resulting from coal fires is unknown. The quantification of this percentage is a future duty of firefighting companies and organizations.

Application of AERMOD model in air quality (PM10) impact assessment of selected opencast mines in The Jharia Coalfield, Jharkhand, India

Application of AERMOD model in air quality (PM10) impact assessment of selected opencast mines in The Jharia Coalfield, Jharkhand, India

Geo-spatial Estimation and Forecasting of LULC Vulnerability Assessment of Mining Activity: A Case Study of Jharia Coal Field, India

Coal is natural deposit minerals and vestibules effect in environment due to operation of mine. Preliminary phase is reconnaissance survey for extraction of coal ores and after that, next operation is happen. In addition, Mining has considered as an eco-unfriendly in natural action but in recent scenarios of Indian coal mines production is very hugs rate with undisciplined nature accompanied by large volumes of hazardous solid, liquid and gaseous material during various mining and related activities. Global aided for the eco-system of mining, associated activities in mining complexes, minimization prevention and extenuation of these encroachments. There are applying geospatial approaches for most important classified classes related to mining activity of land use land cover (LULC) estimation from landsat of four-year data. Vulnerability assessment of classified classes and forecasting of spatial data in future likes features agricultural land, forest, vegetation, mine plantation, scrub land, open cast mine, abandoned mine pit, overburden dump, settlement and water body respectively. It has focused on spatial feature change due to mining activities and mainly use to a case study of Jharia coalfield (JCF), Jharkhand.

Evaluation of geotechnical properties of overburden dump for better reclamation success in mining areas

Coal-mining activities are precursors to land degradation, a part of which is directly related to the generation of huge quantity of overburden (OB) material. The problem of managing OB is mitigated through reclamation, which is directly associated with the geotechnical properties of these dumps. The main objective of this study was to assess the potential of an alternative management plan of OB by analyzing physical properties of these dumps. This alternative management plan of OB could enhance reclamation success by fostering conditions conducive for vegetation growth. This is especially required in old mining areas, where salvaging of topsoil was not done, and as a result, reclamation was affected. For the present study, 12 representative OB samples were collected from two open-cast coal mines (OCP-A and OCP-B) of Bastacolla area in Jharia Coalfield, Dhanbad, India. The samples were analyzed for different geotechnical properties. The results revealed that optimization of these parameters could help in enhancing the reclamation success of the area. From land-use classification, it was observed that about 242 ha of the study area was OB dump; if these areas are reclaimed successfully, then they can act as a potential source of carbon sequestration, and furthermore, they will improve the esthetics and the overall environmental quality at these degraded areas.

Development of a petrographic technique to assess the spontaneous combustion susceptibility of Indian coals

ABSTRACTPetrographic studies are commonly used to categorize the potential utilization of coals. Eleven coal samples from the Jharia coalfield (JCF), India, were studied using petrographic techniques to investigate maceral content, reflectance, and textural characteristics. Multiple test samples of each coal were slowly oxidized under controlled laboratory conditions from an ambient temperature of 30°c to 300°c to investigate the morphology of oxidized coals. The petrographic characterization of coals before and after oxidation showed significant changes in both morphology and vitrinite reflectance. The oxidation of coal particles produced three predominant textural changes: particles with homogeneous change of reflectance (HCv), particles with oxidation rims (ORv), and particles with no changes were observed (Uv), respectively. These textural characteristics were used to indicate how particles had interacted with oxygen at low temperatures during the early stages of oxidation. The morphological classification developed provides an alternative method to confirm the susceptibility of a coal to spontaneous combustion. Conventional thermal parameters such as crossing point temperature (CPT) were unable to identify the coals prone to spontaneous combustion. However, certain petrographic parameters could be combined with CPT values to provide a much more accurate measure for susceptibility to spontaneous combustion.

Microscopic evaluation of inertinite in the coke micro-structure: A case study from Jharia Coalfield, India

ABSTRACTInertinite, a maceral group, which remains inert or partly fuses during the carbonization process, plays a vital role in coke making. During carbonization, vitrinite softens and resolidifies to form porous mosaic texture and loses its original identity whereas, inertinite gets filled up as filler form firmly implanted within different types of mosaic matrix. Their size and association with other maceral or minerals also modify their behavior in coke. Structured and unstructured, smaller and larger, high and low reflectance, oxidation or heat alteration, all behaves in a different manner. The Gondwana coals are characteristically rich in inertinite group of macerals, especially semifusinite which has a wide range of reflectance and morphology varying from vitrinite to fusinite. Present study deals with the behavior of inertinite in Gondwana coals during the carbonization process. Coke petrography is an important tool which gives an insight into the maceral interaction. Different macerals of the inertinite group have been analyzed in coke and compared with their occurrence in parent coal. The study reveals the influence of different inertinite macerals in determining the coke quality.

Impact of Abandoned Opencast Mines on Hydrological Processes of the Olidih Watershed in Jharia Coalfield, India

The Olidih watershed hydrology was affected by opencast mines for the past five decades. This study explores the potential hydrological effect of these mines using Soil and Water Assessment Tool (SWAT2012). The calibration and validation of the model was performed using daily streamflow and sediment yield data (2005–2008) at the outlet of the water shed. The model performed satisfactorily during simulation when tested with statistical indicators. The alternative scenario of no-mines was also modelled to assess the potential impact of abandoned opencast mines for the period 2005–2010. Results show that the abandoned opencast mines play a crucial role in altering hydrological processes of the watershed with 16% increase in the annual sediment yield and reduction of 51% and 6% in annual surface flow and water yield, respectively. This may be due to surface soil disturbance and accumulation of surface runoff in large depressions that resulted in less surface runoff and 13% more groundwater flow. The contribution of this analysis is the application of SWAT in modelling potential hydrological effect of abandoned opencast mines by defining large opencast mines as pothole during simulation.

Assessment of Seasonal and Site-Specific Variations in Soil Physical, Chemical and Biological Properties Around Opencast Coal Mines

Coal mining adversely affects soil quality around opencast mines. Therefore, a study was conducted in 2010 and 2011 to assess seasonal and site-specific variations in physical, chemical, and biological properties of soil collected at different distances from mining areas in the Jharia coalfield, India. Throughout the year, the soil in sites near coal mines had a significantly higher bulk density, temperature, electrical conductivity, and sulfate and heavy metal contents and a significantly lower water-holding capacity, porosity, moisture content, pH, and total nitrogen and available phosphorus contents, compared with the soil collected far from the mines. However, biological properties were site-specific and seasonal. Soil microbial biomass carbon (MBC) and nitrogen (MBN), MBC/MBN, and soil respiration were the highest during the rainy season and the lowest in summer, with the minimum values in the soil near coal mines. A soil quality index revealed a significant effect of heavy metal content on soil biological properties in the coal mining areas.

Abandoned Mine Galleries Detection using Electrical Resistivity Tomography Method over Jharia Coal Field, India

ABSTRACT Land subsidence is a serious problem in Indian coalfields due to old underground mine workings. Unfortunately, most of these are uncharted as no mine plans are available. The hidden galleries, goafs, shafts etc. may pose great threat for future mine development as well as to the local environment. The mine workings should be charted to undertake an effective preventive action. In the present study, 2D electrical resistivity tomography (ERT) technique has been used to detect underground mine workings, mainly air or water filled galleries. Initially, the whole exercise has been executed through a synthetic model study. Gaussian random noise of 5mV/A has been added with synthetic data to demonstrate field condition which provides realistic results. ERT survey was conducted over a part of Jogidih coal mine of Jharia coal field in India for a first time. Four electrode configurations, Wenner, Schlumberger, dipole-dipole and gradient were considered for this study. The results indicate the presence of sub-surface water and air filled cavity due to high resistivity contrast with surroundings.