Using oscillations to detect capillary condensation in MCM-41

In micro- and mesopores of tight, unconventional gas reservoirs, the net gas-in-place may contain significant contributions from adsorbed/condensed gas. In this study, we present a simple and novel oscillation-based method to measure the net gas-in-place with capillary condensation. This method was tested using a synthesized MCM-41 sample and propane gas. The principle of the method is to calculate the effective mass from the frequency of the oscillation of a spring-mass system. A weight holder containing MCM-41 was suspended in a pressure vessel with a series of springs. Frequency of oscillations triggered by a solenoid was measured by the same solenoid connected to an oscilloscope. The mass of co-accelerated gas outside of porous sample (added mass) was determined with the help of non-porous aluminum “cores” of the same cross-sectional area as the weight holder. Argon, a non-condensable gas, was used to measure the pore volume of the MCM-41 sample. Next, propane, a condensable gas, was used to measure the gas-in-place. The mass of propane gas was found to be more than that calculated using real gas law and the pore volume obtained from argon gas measurements. The pore sizes of MCM-41 samples as studied from the literature is around 2 nm. The size of pore that corresponds to the onset of capillary condensation from nitrogen adsorption isotherm in MCM-41 is 0.91 nm. This agrees with the measurement made using our spring-mass system, because the onset of capillary condensation estimated using this pore size is close to the onset observed from our experiment. Hence, the spring-mass method can detect the mass of condensed gas. The resolution of the method, however, should be improved for future quantitative analysis.

Name thesis:degree_name

Master of Science (M.S.)

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Petroleum Engineering

Grantor dc:publisher

Colorado School of Mines. Arthur Lakes Library

Year dc:date.issued

2019

Author dc:creator

• Krishnan, Keerthana

Advisor dc:contributor.advisor

• Yin, Xiaolong

Committee members dc:contributor.committeemember

• Trewyn, Brian
• Prasad, Manika
• Chen, Jinhong

• MCM-41
• capillary condensation
• oscillations

Statement dc:rights

• Copyright of the original work is retained by the author.

Language dc:language.iso

eng, English

Identifier

T 8722

OAI identifier oai:identifier

oai:repository.mines.edu:11124/173065