Temperature-sensitivity of underground gas reservoir storage and its effect on well deliverability

Abstract

The temperature change under alternating injection-production conditions of underground gas reservoir storage is a key factor for permeability and even deliverability. To explore the temperature-sensitivity of sandstone reservoir permeability and its effect on the deliverability of gas well, experimental studies at multiple rounds were carried out within the realistic temperature range of underground gas storage to simulate more accurately. Results show that: (1) Reservoir permeability negatively correlates with temperature. Permeability exhibits a hysteresis effect under cyclic alternating temperature, and the hysteresis effect gradually weakens with the variation of temperature. (2) Permeability and temperature are linearly correlated, and the hysteresis effect does not change with temperature, which is different from stress-sensitivity. (3) Based on the experimental results, a deliverability equation modified with temperature-sensitivity was established. Calculation shows that, ignoring the temperature-sensitivity of permeability will underestimate the performance of gas well, and its effect will aggravate with the increasing elevation and injection flowrate.

Keywords

• gas reservoir storage
• temperature-sensitivity
• hysteresis effect
• injection-production performance
• deliverability equation