The Optimal Selection of the Conditions on Testing Starting Pressure Gradient for Tight Sandstone Oil Fields

Abstract:

In order to optimize select the best experimental conditions on testing tight sandstone starting pressure gradient in the laboratory, the advanced equipment of ASF300^TM Used to do experiments of constant pressure injection and constant flow injection under the conditions of two modes: constant confining pressure and constant net confining pressure, the data obtained was analysed in the form of linear regression fitting, obtained four different starting pressure gradient values under the different conditions. The experimental results and test methods were careful analysed and comprehensive evaluated according to each different experimental conditions and combined with the existing theory. The experimental results indicate that constant flow experiment is not suitable for large-scale use in the laboratory because of its longer time consuming under the condition of constant confining pressure mode, and the starting pressure gradient values are often larger, net confining pressure can be controlled more than 11 MPa to reduce experimental error. Under the condition of constant net confining pressure mode, the result is reliable, but it takes time longer too. On the contrary, the experiment of constant pressure injection takes time shorter, and the results are accurate under the mode of constant net confining pressure. But under the mode of constant confining pressure the value is on the high side. Based on the above, the best condition of testing starting pressure gradient for tight sandstone is net confining pressure mode and the fluid injected in the form of constant pressure.

• Periodical: Applied Mechanics and Materials (Volumes 448-453)
• Pages: 3982-3988
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.448-453.3982
• Online since: October 2013
• Authors: Wei Tian*, Wei Yao Zhu, Hua Yin Zhu, Lai Zhi An, Hai Wen Lai, Huan Zhang
• Keywords: Confining Pressure Control, Effective Stress, Net Confining Pressure, Starting Pressure Gradient, Stress Sensitivity, Testing Condition

References

[1] ChuanLiang Li, Acta petrolei Sinica, 31(2010) 867-870. (In Chinese).

[2] HongEn Dou, Acta petrolei Sinica, 34(2013) 412-416. (In Chinese).

[3] ChengYuan Lü, Jian Wang, Petroleum Exploration and Development, Vol. 29(2002), pp.86-88. (In Chinese).

[4] Ozkan E, Brown M, Raghavan R, Comparison of fractured horizontal-well performance in conventional and unconventional reservoirs[R]. SPE 121290(2009).

DOI: 10.2118/121290-ms

[5] ZhongLiang Yu, Wei Xiong, Natural Gas Technology, 10(2008) 26-29. (In Chinese).

[6] RuiLan Luo, LinSong Cheng , Natural Gas Industry, 29(2009) 46-49. (In Chinese).

[7] Min Ruan, LianGang Wang, Acta Petrolei Sinica, 23(2002) 73-76. (In Chinese).

[8] DaSheng Gu, XueFu Xian, Chinese Journal of Underground Space and Engineering, 8(2012) 1296-1301. (In Chinese).

[9] ChuanLiang Li, Special Oil & Gas Reservoirs, 68(2008) 26-28. (In Chinese).

[10] ChunYan Jiao, ShunLi He , Quan Xie, Acta Petrolei Sinica, 32(2011) 489-494. (In Chinese).

[11] HeAi Ren, ShiXu Zhao , ChengFu Li, Marine Geology Frontier, 28(2012) 60-64. (In Chinese).

[12] Min Li and WenLian Xiao, Chinese Journal of Rock Mechanics and Engineering, 27(2008 supp. 2) 3536-3540. (In Chinese).

[13] ChuanLiang Li, Petroleum Geology &Oil Field Development in Daqing, 25(2006)40-42. (In Chinese).