Development and expansion of the forecast methods of gas kinetics and heat and mass transfer in coal beds with regard to the type of the stress-strain state

Work number - M 12 FILED

Authots:

Molodetskyy A.V., Starikova I. G., Shazhko Ya. V.

Submitted by Institute of Mining Processes NAS of Ukraine

The aimof the work is development and expansion of the forecast methods of gas kinetics and heat and mass transfer in coal beds with regard to the stress-strain state, which is based on the results of fundamental studies of geo-mechanical processes in coal of different degree of metamorphism in the course of loading and fracture under non-uniform compression provoking changes in filtration and diffusion permeability of coal and intensifying the processes of gas release, heat and mass transfer.

The scientific novelty of the workis as follows:

-         regularities of fracture and disturbance of coal are established within the frameworks of the transition between the stress condition of generalized compression to generalized shear. The relation between the degree of impact of methane in coal and increase in the elastic properties and fracture by a mechanism of generalized tension (cleavage) is determined. At the same time, water localizes fracture in the form of generalized shear at any type of stress condition in coal;

-         regularities of methane desorption form a gas-saturated coal bed located in the transition zone from the generalized shear to the generalized tension are determined and express method of evaluation of pressure and methane capacity in bottom-hole area of the bed is substantiated;

-         regularities of  the kinetics of thermal conditions of a coal bed with regard to the degree of disturbance in the area on generalized tension were determined, providing the intensity of oxygen flux and heat loss.

The scientific and practical importanceof the work is:

-         determination of regularities of the impact of non-uniformity of the volume stress state on physical and mechanical properties of coal; development of the method of evaluation of the parameters of the area of the limit state including face slip zone, to be used at the mines with flat pitch.

-         determination of regularities of the kinetics of methane desorption from coal in bottom-hole zone; designed method and measures of the estimation of methane capacity of coal beds in the bottom-hole zone.

-         development of the methods of forecast of the heating tendency of a coal bed, the time of self-heating and self-ignition of coal massifs of different disturbance.

The content of the work is reported in 35 works, including 22 papers in scientific journals certified by Higher Attestation Commission of Ukraine, 11 reports in Collections of works of conferences, 2 patents. The results of the work contributed to the development of 2 regulatory documents