Aquifer hydraulic conductivity characterization by inflatable packer method in the underground coal gasification process

Abstract

Underground coal gasification technology is a technology that converts coal into gaseous products through the gasification process. UCG technology is known as clean energy technology. The potential risk of UCG that can occur is groundwater contamination, this is due to gas leaking into the rock layers and the aquifer above it. An important parameter of groundwater contamination is hydraulic conductivity, obtained by the double inflatable packer method. The test results of aquifer-03 (142-151 m), the hydraulic conductivity value is 1.82 e-6 m/s - 2.16 e-6 m/s, the aquifer zone order range from the upper limit to the lower limit tends to be homogeneous in sand lithology. fine. The top layer of aquifer-04 (213-230 m), is silt lithology, the middle is silty sand lithology and the bottom is silty sand lithology. The hydraulic conductivity value is 1.22 e-6 m/s - 3.88 e-8 m/s, the range is quite wide with a difference of 2 orders, this is due to differences in grain lithological composition with finger type aquifer layers and are not interconnected. If there is a gas leak, then aquifer-03 lithology is more affected as a medium for spreading groundwater pollution than aquifer-04 lithology.