Experimental hydraulic dissociation of Boldyrev seam coal using access boreholes in Kirov mine

The mechanism of hydraulic dissociation of coal at the stage of pre-mining methane drainage using access boreholes is presented. Efficiency of hydraulic dissociation with creation of cyclic micro fracs is proved. It is required to integrate all in-seam gas drainage activities. In 2019 appraisal survey was implemented in Kirov mine, SUEK-Kuzbass. Integrated gas drainage can reduce methane content of coal, increase its residual gas content, alter its rheological properties and reduce outburst hazard, which, in the aggregate, can increase output per face owing to weakening or removal of a «gas barrier» in large-scale coal mining. The actual hydraulic dissociation design is described for a typical borehole. The hydraulic treatment parameters enabling gas flow, hydraulic dissociation and hydraulic fracturing modes are obtained. The observed phenomenon of coal swelling can further be utilized to stimulate in-seam methane drainage. It is found that pressurization rate of 100 l/s is critical in case of the present test conditions and decreases coal seam intake. As a consequence, the undesirable mode of hydraulic fracturing takes place at the final stage of hydraulic treatment. The experimental research has proved the efficiency of the proposed technology for pre-mining gas drainage with hydraulic dissociation of using access boreholes.

Meshkov A. A., Sadov A. P., Komissarov I. A., Khautiev A. M.-B., Slastunov S. V. Experimental hydraulic dissociation of Boldyrev seam coal using access boreholes in Kirov mine. MIAB. Mining Inf. Anal. Bull. 2020;(11):37-45. [In Russ]. DOI: 10.25018/0236-14932020-11-0-37-45.

A.A. Meshkov¹, General Director,
A.P. Sadov¹, Director, Department Control of Degassing and Methane Utilization, e-mail: sadovap@suek.ru,
I.A. Komissarov¹, Deputy Chief Engineer, Department Control of Degassing and Methane Utilization, e-mail: komissarovia@suek.ru,
A.M.-B. Khautiev¹, Engineer-Technologist, Department Control of Degassing and Methane Utilization, e-mail: khautievam@suek.ru,
S.V. Slastunov, Dr. Sci. (Eng.), Professor, e-mail: slastunovsv@mail.ru, Mining Institute, National University of Science and Technology «MISiS», 119049, Moscow, Russia,
¹ SUEK-Kuzbass JSC, 652507, Leninsk-Kuznetskiy, Russia.

S.V. Slastunov, e-mail: slastunovsv@mail.ru.

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