Shandong University

Zhiyuan Liu

Gang Wang

Lulu Sun

Zhen Liu

Weimin Cheng

Guanhua Ni

Qiming Huang

Jianqiang Chen

Yanbin Yu

Yixin Liu

Hao Xu

Sanlong Zheng

Xiangyu Tang

Xiangjie Qin

Kunlun Liu

Jiuyuan Fan

A deep low-permeability gassy seam drilling-slitting-sealing-fracturing drilling device includes a drilling control system, a high-pressure water power system, a water pressure grading control system and a fracturing and sealing control system. The drilling control system adjusts a drilling direction a water supply pressure of the drill rod, the high-pressure water power system supplies high-pressure water with different pressures to the device, and the water pressure grading control system ensures that a water pressure for flushing drill cuttings is less than 5 MPa, a water pressure for slitting in a direction perpendicular to a length of the drill rod is 25-35 MPa, a water pressure for sealing with a borehole sealing capsule is 35-40 MPa, and a water pressure for further pressure relief and permeability increasing of a coal seam is 40-50 MPa. The fracturing and sealing control system controls borehole sealing and hydrofracturing operations.

Drilling-slitting-sealing-fracturing device and method for a deep low-permeability gassy coal seam

A steeply-inclined ultra-thick coal seam gas control method based on a binary composite liquid. The method includes taking a clean fracturing fluid system and a microemulsion as a binary composite liquid. The method includes injecting the binary composite liquid into a coal mass by means of a main hydraulic fracturing and permeability improvement method of hydraulic fracturing and water jet slotting to form a coal mass gas extraction system of binary composite liquid fracturing and permeability improvement. The method includes investigating and analyzing a gas control effect of the steeply-inclined ultra-thick coal seam according to change characteristics and analysis of gas extraction flow rate, change characteristics and analysis of permeability coefficient of coal seam, change characteristics and analysis of gas natural desorption speed of coal mass, change characteristics and analysis of gas concentration of return air flow of working face and theoretical analysis of drilling cuttings index.

Steeply-inclined ultra-thick coal seam gas control method based on binary composite liquid

Growing community of inventors

Qingdao, China

Zhiyuan Liu