1、英文原文Recent Developments and Practices to Control Fire in Undergound Coal MinesS. K. Ray* and R. P. Singh, Central Mining Research Institute, Barwa Road,Dhanbad, Jharkhand 826 001, IndiaAbstract: Coal mine res cause serious threat to the property and human lives. Out-break of re may be dealt with adv
2、anced re suppression techniques like Infusion of inert gases or liquid nitrogen, Dynamic Balancing of pressure, Reversal of under-ground mine ventilation, Application of nitrogen foam, Inertisation of Goaf, Water mist etc. The paper addresses all those control techniques in detail. Success story of
3、controlling res in coal mines of different parts of the world are reported. Results of a recently completed Science & Technology (S&T) project with regard to various re suppression techniques like Infusion of liquid nitrogen, Injection of high pressure high stability nitrogen foam, and Water mist on
4、 open re are also discussed.Keywords: coal mine re, reversal of underground mine ventilation, nitrogen foam, inertisation of goaf & water mist1. IntroductionSince inception, mining is considered as a most hazardous and dangerous of peacetime activities. An outbreak of re in the underground workings
5、of a mine poses a direct threat from the re itself. Further, an invisible and immediate threat from carbon monoxide poisoning and an explosion, particularly in gassy coal mines is also there. It affects to both persons working underground at the time of the outbreak and to those involved in the subs
6、equent rescue and re ghting. It hampers the coal production and sometimes loss of coal winning machinery. Fires in coal mines may be categorised into two groups viz.,(a) res resulting from spontaneous combustion of coal (b) open res, which are accidental in nature, caused as a result of ignition of
7、combustible materials.In coal mines, res are generally caused due to several reasons viz., sluggish ventilation, high pressure difference across intake and return airways, loose and fallen coal in the goaf area, electricity, mechanical friction, blasting, welding, explosions and illicit distillation
8、 of liquor.2. Mine Fire Model Gallery To understand the complex dynamic phenomenon of open res (res that occur in mine airways usually commence from a single point of ignition) and to study the effectiveness of various re suppression techniques viz., liquid nitrogen, high pressure high stability nit
9、rogen foam and water mist, recently Central Mining Research Institute, Dhanbad, India has designed and constructed a Mine Fire Model Gallery. The model gallery is 65.5 m long; arch in shape with a base of 2.4 m and crown height of 2.7 m. The cross section of the gallery is 5.86 m2. The gallery is di
10、vided into ring and non-ring zones. An exhaust type axial ow fan having a capacity to deal with 25 m3/s. of air quantity at 50-mm wg pressure has been installed at its end. The gallery is provided with two sliding doors for quick sealing of the re and a rolling shutter for regulation of desired airo
11、w. An isometric view of mine re model gallery is shown in Figure 1.It is equipped with a state-of-the-art computer aided on-line telemonitoring system. The system consists of 130 sensors (98 temperature, 25 gas, 3 pressure, 2 heat ux, 1 each velocity and Suspended Particulate Matter (SPM) concentrat
12、ion sensor) and instruments with data logger, computer, computer peripheral etc. for continuous monitoring of various re parameters like gas concentration (O2, CO2, CO, CH4 & H2), air velocity, pressure across re zone and fan pressure, temperature, heat ux, dust and particulate matter concentration
13、inside the gallery.Figure 1 Isometric view of mine re model galleryDetails of the construction of the gallery and its instrumentation system have beendescribed elsewhere In the experiments inner side of the ring zone of the gallery which is 22 m in length (ring zone starts from 10.5 m from the entry
14、 of the gallery) was lined with a thin layer of coal slabs, 810 cm thick, brought from Dobrana seam of New Kenda Colliery. Fixing of coal slabs were effected with a mixture of air setting cement and liquid binder. In each set of experiments about 1820 tons of coalswere used.The paper addresses all t
15、he above control measures that have been applied all over the world. Results of experimentation on open res in Mine Fire Model Gallery are also discussed.3.Fghting Mine Fires3.1 High Pressure FoamUse of foam plugs has been successful in ghting mine res in roadways where direct attack with water is n
16、ot possible. USBM studies reveals that the water content of the foam should not be less than 0.20 kg/m3 otherwise the foam is not capable of controlling the re. With sucient ventilating forces (around 8 cm wg) properly generated foam may be transported over 300 m. Foam does not appear to be effective against deep seated, rapidly advancing, buried or dead end res.In India, suppression of spontaneous
