压力溶浸作用下钙芒硝盐岩力学特性基础研究

Basic Research on Mechanical Properties of Glauberite Salt Rock Under Pressure Leaching

目前钙芒硝矿多采用就地溶浸或井工开采方法,效率低、污染大,基于原位改性采矿理论欲对其实现固体矿物流体化开采,因此通过室内模拟压力水溶浸钙芒硝盐岩,并对其强度变化进行分析。试验发现:压力溶浸过程中矿物胶结处较先产生裂缝,压力溶浸环境下盐岩强度弱化程度大于自然溶浸下盐岩强度的弱化,弱化程度随着溶浸压力的增大而增大,在1.0MPa和1.5 MPa压力水环境下溶浸24h之后,试样强度的弱化系数分别为0.67,0.55。1.0 MPa压力水环境下溶浸7d之后,试样强度的弱化系数为0.34,压力溶浸对盐岩强度的弱化在溶浸初期影响显著,随后时间因素占主导地位。通过拟合得出钙芒硝盐岩强度与压力溶浸时间的关系,为实现钙芒硝矿固体矿物流体化开采提供一定的理论基础。

At present,in-situ leaching or well-working mining methods are mostly used in glauberite mines,which are inefficient and polluting.Based on in-situ modified mining theory,the fluid mining of solid minerals need to be realized.Therefore,the pressure water leaching of glauberite salt rock was tested in laboratory,and its strength change was analyzed.It is found that cracks occur in the cementation of minerals during pressure leaching.The strength weakening degree of salt rock under pressure leaching environment is greater than that under natural leaching,and increases with the increase of leaching pressure.The strength weakening coefficient of samples is 0.67 and 0.55 after 24 hours of leaching in 1.0 MPa and 1.5 MPa of pressure water environment,respectively,while is 0.34 after 7 days of leaching in 1.0 MPa of pressure water environment.The weakening effect of pressure leaching on strength of salt rock is significant at the initial stage of leaching,and then time factor is dominant.The relationship between strength of glauberite rock and pressure leaching time is obtained by fitting,which provides a theoretical basis for the realization of fluid mining of solid minerals in glauberite mines.