CONNECTION OF ACOUSTIC EMISSION PARAMETERS WITH FILTRATION-COLLECTIVE PROPERTIES OF THE MASSIF AND THE PUMP UNIT PERFORMANCE FOR HYDRAULIC PROCESSING OF ROOF AND COAL-LAYER
The results of studies on the establishment of functional relationships between the acoustic emission (AE) parameters and the filtration-collection and strength properties of the rock mass were presented, as well as the parameters of the pumping unit for several methods of hydroprocessing a mountain...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
"VostECO" Ltd
2018-03-01
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| Series: | Vestnik Naučnogo Centra po Bezopasnosti Rabot v Ugolʹnoj Promyšlennosti |
| Subjects: | |
| Online Access: | https://ind-saf.com/uploads/s/l/d/a/ldab4xgicwcd/file/7Kfn9w0X.pdf |
| Summary: | The results of studies on the establishment of functional relationships between the acoustic emission (AE) parameters and the filtration-collection and strength properties of the rock mass were presented, as well as the parameters of the pumping unit for several methods of hydroprocessing a mountain massif in coal mines in order to reduce the danger of dynamic phenomena.It was shown that for effective low-pressure humidification of coal, the activity of the AE should not exceed the background value measured before the injection of liquid into the mountain mass.When the formation is hydrodisturbed, the activity of the AE acquires an additional to the background component, which is determined by the porosity and permeability of the formation, the viscosity of the liquid, the pressure drop of the fluid from the crack walls to the filtration front, the geometric dimensions and orientation angles of the developing cracks, the ratio of the vertical and horizontal components of the rock pressure, and the time of injection. Moreover, the dependence of the AE activity on time at a constant injection rate is such that when the fluid pressure in the well rises at the initial stage, it rapidly increases from the background value to the maximum value, and then decreases as the size of cracks and the filtration flow of liquid into their walls increase. With an increase in the injection rate, the time to breakthrough the fluid along the growing cracks on the face and the volume of the injected liquid decreases, and the AE activity values increase.With the directed fracture of the roof of the formation, the length of the growing crack is related to the total number of pulses of the AE by an exponential dependence, which makes it possible to estimate the length and area of the growing crack from the measured number of AE pulses.The study was carried out through a grant from the Russian Science Foundation (project No. 17-17-01143). |
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| ISSN: | 2072-6554 2072-6554 |