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Panigrahi, Durga Charan
- 222Rn Distribution Pattern in Dwellings of Copper Mineralized Area of East Singhbhum Region, Jharkhand, India
Abstract Views :251 |
PDF Views:82
Authors
Asheesh Mishra
1,
R. Lokeswar Patnaik
2,
Vivekanand Jha
2,
Shailendra Kumar Sharma
3,
Durga Charan Panigrahi
4,
Akshaya Kumar Sarangi
5
Affiliations
1 Atomic Energy Central School, Jaduguda Mines, Jaduguda, East Singhbhum 832 102, IN
2 Environmental Assessment Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, IN
3 Department of Applied Physics, Indian School of Mines, Dhanbad 826 004, IN
4 Department of Mining Engineering, Indian School of Mines, Dhanbad 826 004, IN
5 Uranium Corporation of India Limited, Jaduguda, East Singhbhum 832 102, IN
1 Atomic Energy Central School, Jaduguda Mines, Jaduguda, East Singhbhum 832 102, IN
2 Environmental Assessment Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, IN
3 Department of Applied Physics, Indian School of Mines, Dhanbad 826 004, IN
4 Department of Mining Engineering, Indian School of Mines, Dhanbad 826 004, IN
5 Uranium Corporation of India Limited, Jaduguda, East Singhbhum 832 102, IN
Source
Current Science, Vol 108, No 10 (2015), Pagination: 1931-1938Abstract
Seasonal variation of 222Rn levels was studied in the dwellings in U-Cu mineralized area of East Singhbhum, Jharkhand, India. Copper mining and processing industry is operational in this area for the last hundred years. Copper minerals of this region contain a significant fraction of uranium and the decay products. To measure the activity concentration of 222Rn, LR-115, type-II solid-state nuclear plastic track detector was used in an indigenously developed radon dosimeter cup. A higher value of 222Rn activity concentration was recorded in some of the dwellings in the mineralized zone. The results at different locations adjoining the facilities show that the 222Rn activity concentration varies to a great extent following an approximate log-normal distribution. The observed range varied from 29.1 and 314.6 Bq m-3 with an overall geometric mean of 72.3 Bq m-3 and geometric standard deviation 1.67. Further, in poorly ventilated dwellings 222Rn levels were higher compared to the properly ventilated houses. The peak activity concentration of 222Rn was recorded during winter (December-February). Appreciably lower activity concentration of radon was observed during summer and rainy seasons. The results reflect that the levels are higher than the global average indoor activity concentration of 40 Bq m-3 (UNSCEAR-1993) for 222Rn, but are comparable to the studies carried out in similar types of geological formations.Keywords
Copper Mining, Dwelling Ventilation, Radon Distribution, Seasonal Variations.Full Text
- Numerical Studies of Ventilation Effect on Methane Layering Behaviour in Underground Coal Mines
Abstract Views :281 |
PDF Views:98
Authors
Affiliations
1 Department of Mining Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826 004, IN
1 Department of Mining Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826 004, IN
Source
Current Science, Vol 112, No 09 (2017), Pagination: 1873-1881Abstract
Layering of methane in underground coal mines owing to poor ventilation leads to methane explosion hazard. We study the methane layering phenomenon and the effect of ventilation on dispersion of methane in underground coal mines at air velocities varying from 0.5 to 4.0 m/s. Three-dimensional simulations using CFD code ANSYS Fluent 12.0 were performed assuming the flow to be unsteady, turbulent and incompressible. The study demonstrated that ventilation significantly affects the behaviour of methane layering and dispersion of methane in underground coal mines. The layering length decreased with increase in air velocity. At air velocity of 4.0 m/s, the methane layering length considerably reduced to a safer level of about 1 m. Moreover, the simulation results showed a good agreement with the experimental results.Keywords
Methane Layering, Numerical Simulation, Underground Coal Mine, Ventilation Effect.Full Text
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