摘要

This paper describes a newly developed device for measuring the CO2 permeability coefficient in porous rocks under reservoir conditions, in which the pressure and temperature of injected CO2 are usually beyond the critical point of 7.38 MPa and 31.8 degrees C. The device consists of a pressure cell, a syringe pump for CO2, a pressure amplifier, a heating unit, and a measurement system. Two buffer tanks are set at the inlet and outlet of the seepage chamber to maintain stable CO2 injection and back pressures during testing. The supercritical CO2 flowing through the rock sample is depressurized to the gaseous phase to measure its flow rate at low pressure. An average flow rate over time is used to calculate the permeability coefficient of CO2 in the rock sample. A performance test was conducted to demonstrate the detailed characteristics of the device. A sample application using silt rock for testing proved that the device can effectively measure the permeability coefficient of supercritical CO2 in porous rock.