Mines, rock dust

Permissible electrically operated rock-dust distributors. U. S. Bur. Mines Rept Investigations 3345... 

The region in which the blasting is done must be kept well protected by rock dust or otherwise be in accordance with Bureau of Mines inspection standards. 

Barium is released primarily to the atmosphere as a result of industrial emissions during the mining, refining, and production of barium and barium chemicals, fossil fuel combustion, and entrainment of soil and rock dust into the air. In addition, coal ash, containing widely variable amounts of barium, is also a source of airborne barium particulates. Most barium released to the environment from industrial sources is in forms that do not become widely dispersed. In the atmosphere, barium is likely to be present in particulate form. Although chemical reactions may cause changes in speciation of barium in air, the main mechanisms for the removal of barium... 

Rock Dust [Georgia Marble] Ground calcium carbonate filler for coal mine dusting. 

Occupational diseases that affect the health of workers, to cause premature workers lose the ability to work the main factors. Mine occupational hazards in dust (coal dust, rock dust, cement dust, etc.), chemicals (nitrogen oxides, carbon oxides, sulfur dioxide, hydrogen sulfide, etc.) and physical factors (noise, vibration, thermal radiation, high temperature, etc.) three categories. Which is the most serious to dust hazards caused by pneumoconiosis. 2009,14,495 cases of pneumoconiosis new cases, the CWP and sand lung accounted for 91.89%. The incidence of pneumoconiosis shorten the length of service, the mass of pneumoconiosis... 

Eventually it was realized that coal dust presents a far greater danger than methane insofar as dust explosions are far more violent in character and widespread in effect than firedamp explosions (Torrent et al., 1991). These latter are usually fairly localized in their effect but the danger lies in the fact that a relatively minor firedamp explosion may initiate a far more serious coal dust explosion. Precautions taken against the occurrence of coal dust explosions include the deposition of incombustible rock dust on the mine surfaces to suppress propagation of the explosion. 

D. B. Bekirbaev et at, Controlling Coal and Rock Dust in Mines, Gosgortekhizdat, Moscow (1959) ... 

The report found that Massey failed to properly examine the mine to locate and fix hazards and violations control the accumulation of coal dust in the mine by adequately rock dusting maintain water spray systems on the longwall cutting shearer submit an effective mine... 

Stage 10. A typical mass size distribution of aerosols as measured by the MOUDI cascade impactor in a coal mine using diesel-powered equipment where the concentration was much higher and the run times shorter (90 min) is shown in Figure 6.16. These data indicate a bimodal distribution with the lower and the upper modes consisting of diesel exhaust particles and coal and rock dust, respectively. 

The elimination of underground smoking and open-flame lamps The required use of rock dusting The use of water sprays for dust reduction The mandatory use of pre-shift examinations for mine gases. 

There was a dangerous accumulation of methane in that mine that day. I would like for you to remember that that was the cause of the disaster, an accumulation of methane, coupled with the lack of rock dust, coupled with the... 

The Southmountain interviews thus allow us to examine one aspect of the rhetorical transformation of experience when local knowledge moves into the domain of science where it is captured and transformed in writing. But these interviews also demonstrate how easily the absence of any sort of negative feedback can create a sense of complacency that can lead to disaster. In fact, one of the questions that is never explicitly stated is why miners who heard bumps did not communicate with management or persuade management to take a different course of action. When Shane describes how the rock dust always kept going toward the outside, investigators ask if this was normal. They are particularly concerned about the direction of dust flow in the mine, which seems to indicate problems with the ventilation system prior to the accident. But that concern did not move individuals to action. 

The use of phosphate and potash fertilizers, both derived from specific sedimentary rocks through mining rocks, have also increased substantially (Table 6.7). Both are produced by the mechanical processing of rock which requires fossil-fuel energy and both generate dust as a pollutant. There is unlikely to be any abatement in fertilizer production/ consumption... 

In 1955 it was discovered that mixtures of ammonium nitrate and fine coal dust have satisfactory blasting capabilities in large (9 inch) holes used in open-pit coal mines to remove the rock and soil covering the coal. Polyethylene bags containing this material deform to fit the hole and provide moderate water resistance. ANFO is used in open-pit iron and copper mines and for construction such as road building. The mixture is air blown into 2-inch holes or less m maiiv underground mines. 

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