To solve various technological problems of mining, such as, prevention of air inflow into coal-seam degassing holes and steam entry into underground galleries when thermoshaft production of heavy oil is performed. There are developed the chemical compositions to form the membranes' impermeable and drainage elements. Also, there is provided the stand's description and laboratory studies' results which are the compositions' influence on permeability of porous medium. A method of creating membranes by hydraulic fracturing of the rocks, in which to get a transverse fracture, shear loading of the walls along the wellbore axis is used. A comparative analysis of this method with directional hydraulic fracturing on the basis of slot initiator is performed. In the article calculations of influence of the fracture pressure and fracture propagation from the wellbore and fracture radii are presented. The technological advantages of the developed method of hydraulic fracturing for the creation of impermeable membranes are represented.
In mining the impervious membranes are used to protect a mine working from water and gas inflow and to create edges of the metals leaching zone and etc. Among these purposes there is prevention from air filtering from the mine working into degassing boreholes. The sealing quality estimates the efficiency of the preliminary coal beds degassing. There is a problem of the air inflow into methane withdrawal point through the rock mass. A well-known solution addressing the problem is to apply insulating compound onto the mine working surface. Its uneven surface causes great specific consumption of expensive chemical reagents. However, isolation of a surface part around the degassing borehole head does not interfere with the air filtering through the disturbed rock bed around the mine working made out of its non-isolated parts.
More effective solution is impervious membranes created inside of the rock mass with the help of one or several hydraulic fracturing fractures parallel to each other and located across an uncased borehole. This paper suggests several schemes for the membranes made of drainage and impermeable elements. In order to obtain the elements a fill fluid and insulating compound have been created. The work presents results of the laboratory research on the fill fluid and insulating compound's influence on porous medium permeability.
