Cascade construction of geological model of longwall panel for intelligent precision coal mining and its key technology

Intelligent precision coal mining represents the trend of mining industry with the national integration of infor- matization and industrialization. Lots of coal enterprises and research institutes have carried out a series of experimental researches and industrial demonstration projects of intelligent precision coal mining. However, the insufficient adaptability of geological conditions has been a technical bottleneck of intelligent and precise coal mining. It is urgent to construct a high-precision and transparent 3D geological model for coal long-wall panel. Based on an intelligent longwall panel of Huangling Coal Mine,the spatio-temporal demand of geological transparency for intelligent precise coal mining has been analyzed. On the one hand,it is necessary to ensure the transparency of the geological conditions in a certain range of unmined area in front of the working face;and on the other hand,it is necessary to update the 3D geological model of the transparent longwall panel for every cutting cycle dynamically. Based on the analysis of the cur- rent situation of geological exploration technologies and the level of central control,the general idea of constructing 3D geological model of transparent longwall panel has been put forward. According to different geological exploration and mining stages,the 3D geological model of working face can be classified into four stages,which are black,gray,white and transparent box models. In the long-wall panel planning and design stage,the geological “ black box” model can be constructed based on the ground boreholes and 3D seismic data,and its precision is about 10-meter. When the in- take and return airways and start-up room are excavated,the geological “gray box” model can be established based on the geological data from ground and underground,such as boreholes,roadways and the dynamic interpretation of 3D seismic data,and its precision is about 10-to 1-meter. In pre-mining,the “gray box” model can be refined into “white box” model by using in-seam seismic technology and the gateway radio wave penetration technology. The precision of “white box” model is about 1-to sub-meter. During the coal mining period,a local area within 50 m ahead working face is transparent based on the dynamic combination of mining data and seismic while coal mining monitoring results. The precision of transparent model is about sub-meter. To construct above four models,the following five key technolo- gies / equipments should be developed:① Geological dynamic interpretation of 3D seismic data;② Geophysical explo- ration technology and equipment in drill holes;③ Seismic monitoring technology while coal mining;④ Geological in- formation extraction of working face monitoring data;and ⑤ Multi-source heterogeneous geological information dynamic fusion. In this way,a dynamic transparent model could be constructed gradually during the process of mining,aiming to provide geological supports for the precision coal mining.