Predicting the critical drawdown pressure of sanding onset for perforated wells in ultra‐deep reservoirs with high temperature and high pressure

Abstract

The ultra-deep reservoir is characterized by huge reserves and high productivity with high temperature and pressure, which has broad exploration and development prospects. In recent years, sand production often occurs in this kind of reservoirs such as Nanyuan oilfield, Dina gas reservoir, and Tarim Basin in China (Figure 1). Sanding onset has caused serious safety

Critical drawdown pressure prediction for sanding production of underground gas storage in a depleted reservoir in China

“…The radial, tangential, and axial stress in the cylindrical coordinate system of the wellbore surrounding are as follows 42 : (2) (3) At this point, the shear stresses around the well are as follows 42 :…”

“…As shown in Figure 2B, a micro‐element is taken from the rock around the well wall for the stress balance analysis. The stress field of this micro‐element is $$\left(\begin{array}{ccc}{\sigma }_{x} & {\sigma }_{xy} & {\sigma }_{xz}\\ {\sigma }_{xy} & {\sigma }_{y} & {\sigma }_{yz}\\ {\sigma }_{xz} & {\sigma }_{yz} & {\sigma }_{z}\end{array}\right)$$, then the stress tensors in the converted coordinate system can be expressed as 42 : $$$\left\{\begin{array}{c}{\sigma }_{x}=({S}_{H}{\cos }^{2}\beta +{S}_{h}{\sin }^{2}\beta ){\cos }^{2}\theta +{S}_{v}{\sin }^{2}\theta ,\\ {\sigma }_{y}={S}_{H}{\sin }^{2}\beta +{S}_{h}{\cos }^{2}\beta ,\\ {\sigma }_{z}=({S}_{H}{\co...$$…”

“…The radial, tangential, and axial stress in the cylindrical coordinate system of the wellbore surrounding are as follows 42 : $$${\sigma }_{R}=\frac{{R}_{w}^{2}}{{R}^{2}}{p}_{w}+\frac{1}{2}({\sigma }_{x}+{\sigma }_{y})\left(1-\frac{{R}_{w}^{2}}{{R}^{2}}\right)+\frac{1}{2}({\sigma }_{x}-{\sigma }_{y})\left(1+\frac{3{R}_{w}^{4}}{{R}^{4}}-\frac{4{R}_{w}^{2}}{{R}^{2}}\right)\cos \,2\alpha +{\sigma }_{xy}\left(1+\frac{3{R}_{w}^{4}}{{R}^{4}}-\frac{4{R}_{w}^{2}}{{R}^{2}}\right)\sin \,2\alpha ,$$$ $$${\sigma }_{\alpha }=-\frac{{R}_{w}^{2}}{{R}^{2}}{p}_{w}+\frac{1}{2}({\sigma }_{x}+{\sigma }_{y})\left(1+\frac{{R}_{w}^{2}}{{R}^{2}}\right)-\frac{1}{2}({\sigma }_{x}-{\sigma }_{y})\left(1+\frac{3{R}_{w}^{4}}{{R}^{4}}\right)\cos \,2\alpha -{\sigma }_{xy}\left(1+\frac{3{R}_{w}^{4}}{{R}^{4}}\right)\sin \,2\alpha ,$$$ …”

“…However, sand production has been reported in the UGS of the depleted oil and gas reservoir, such as Wen 96, Wen 23, Hutubi in China, Redfield, Vincent, Hillsboro in America, Hajdúszoboszló, Haidach in Europe. The development mode and operation rules of UGS, for example, the cycling gas injection and extraction, are different from those of traditional oil and gas reservoirs 38–42 . These factors were not taken into account in sand production studies on the development of the reservoir, which could not be fully applied to UGS in depleted oil and gas reservoirs.…”

“…The development mode and operation rules of UGS, for example, the cycling gas injection and extraction, are different from those of traditional oil and gas reservoirs. [38][39][40][41][42] These factors were not taken into account in sand production studies on the development of the reservoir, which could not be fully applied to UGS in depleted oil and gas reservoirs. Song et al accurately predicted CDP based on inversion results of numerical simulation of the geo-stress in the target reservoir, combined with experiments and logging data.…”