| Gas permeability for tight reservoir core samples are measured with various upstream, downstream, and average pressures. It is found that exerting a backpressure at the outlet of a core sample can effectively reduce the gas slip effect and improve permeability measurements. When the backpressure reaches a certain level, defined as the minimum backpressure, the gas slip effect can be eliminated so that non-slip gas permeability can be obtained. When the backpressure exceeds the minimum backpressure, the measured non-slip permeability is a constant for a given core sample. Experimental results also indicate that the minimum backpressure increases as the permeability of a given tight reservoir core decreases.; Gas and liquid flow tests are performed by using ethane and carbon dioxide as the flowing fluids when they are in gaseous state and in liquid state, respectively. The experimental results indicate that liquid permeability systematically deviates from gas permeability in tight porous media. (Abstract shortened by UMI.)... |
