Reasonable offset distance for the synergetic development of longwall coal mining and in-situ leaching uranium in coal series
HUANG Bingxiang
LUO Ying
HAN Xiaoke
ZHAO Xinglong
Abstract：In-situ leaching mining of sandstone-type uranium ores is based on the technical prin-ciple of water retention and pressure stabilization,whereas longwall mining of coal mines takes dewatering and pressure reduction as a safety prerequisite.The contradiction in their co-mining is essentially a conflict regarding the spatial demand for the groundwater system.To funda-mentally alleviate the contradictions in the co-mining of coal and uranium resources,a method for determining the reasonable offset distance for the coordinated development of coal and ura-nium is proposed based on the interaction mechanism of coal-uranium co-mining.The disturb-ance characteristics of the uranium-bearing aquifer caused by the four stages,namely coal mine roadway exposure,pre-mining dewatering and drainage,mining operation,and post-mining closure,were systematically analyzed.On this basis,the optimal orientation of the offset dis-tance perpendicular to the regional groundwater flow direction was determined,and based on the requirement of in-situ leaching uranium mining for confined water head,the principle for determining the reasonable offset distance to prevent the groundwater drawdown funnel caused by coal mining from crossing the boundary to the uranium mining area was established.Based on the big well theory,a calculation model for the influence radius of the groundwater draw-down funnel caused by coal mining was established under two occurrence modes,namely"up-per coal and lower uranium"and"upper uranium and lower coal".According to the established model,the reasonable offset distance for coordinated mining of two typical coal-uranium sym-biosis modes in the southern margin of the Ili Basin and the northern part of the Ordos Basin was quantitatively determined.The results show that under the layout conditions perpendicu-lar to the regional groundwater flow direction,the minimum required safety offset between Ili No.1 Coal Mine and the Kujiertai-Honghaigou Uranium Mine is 2.7 km,while a minimum safety distance of 7.5 km is required between the Tarangaole Coal Mine and the Nalinggou U-ranium Mine.
Keywords：coal and uranium coexistencelongwall coal miningin-situ leaching of uraniumcoordinated miningreasonable offset distance
Publication Date：2025-11-30
Online Publishing Date：2026-01-09(First online date of this platform, not the publication date of the document)
Pages：18( 1416-1433 )