Abstract
In this paper, we present the problem of gas and dolomite outbursts in copper mines. The energy balance of the phenomenon is analyzed. An examination of the porosity of the dolomites is performed; in addition, the content and pressure of the gas accumulated in the pore structure of the rock are determined. The gas energy accumulated in the pore space of rocks is determined depending on the transformation occurring during gas decompression. The work needed to crush the rock for the grain distribution characteristic of post-outburst masses is examined. The gas energy needed to transport rocks is analyzed. The purpose of the research is to determine the limit values of parameters describing the gas and rock system for which there is a risk of dolomite and rock explosions. For the characteristic porosity of dolomites of −5%, gas and rock outbursts at 5 MPa pressure in isothermal transformation can be expected, and if the transformation is closer to adiabatic transformation, outbursts can be expected at 10 MPa pressure.
Highlights
The energy balance of the phenomenon is analyzed
To give a picture of a gas and rock outburst, it is necessary to examine the course of the process
A gas and rock outburst can be stopped if the ejected material fills the working space in a way that prevents the further transport of the material, or the energy accumulated in the rock is insufficient to break and transport the rock
Summary
Gas-induced geodynamic hazards occur in mining when gas, at a significant pressure, is present in the pores and crevices of the solid rock. The authors adhere to the theory that the chief role in the initiation and course of an outburst of gas and rock is played by gas at a significant pressure contained in the pores and crevices of the rock. The energy balance of the phenomenon is presented as the total work that gas contained under a certain pressure in a porous of rock is able to “produce” by expanding; on the other hand, the phenomena that absorb this work—rock fragmentation and its transport deep into the excavation site—must be considered. After exceeding one of the parameters (porosity or gas pressure), it will be possible for a burst to occur, because the work that the gas performs will be greater than that necessary to crush and transport the rock
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have