Variation law of cementing stone permeability in gas storage
The permeability of the cementing stone is a key parameter affecting the long-term sealing of gas storage.In this study,the permeability of the cementing stone was tested by using the ultra-low permeability gas permeability measuring instrument under different confining pressure,constant confining pressure and increasing-decreasing effective stress,and the influence mechanism of different pressure conditions on cementing stone permeability was analyzed.The variation law of cementing stone permeability was revealed through a mathematical fitting method.The results show that the permeability of cementing stone decreased with the increase of confining pressure.Under constant confining pressure and with the increase and decrease of effective stress,the permeability of cementing stone firstly decreased and then increased,and due to the internal structure damage of cementing stone,the permeability of cementing stone in the effective stress decrease stage was higher than that in its increase stage.The permeability of cementing stone calculated by the linear superposition method combined with the existing permeability model was higher than the actual permeability test results.The new mathematical model considered the influence of confining pressure and effective stress,and could accurately predict the change of cementing stone permeability under different pressure conditions in gas storage.The research results provide a novel method for predicting the cementing stone permeability in gas storage during the injection-production service period,which can provide key parameters for percolation analysis of the cementing sheath in gas storage.
万方数据
维普
