Joule–Thomson Effect on a CCS-Relevant (CO₂ + N₂) System

Abstract

The Joule–Thomson effect is a key chemical thermodynamic property that is encountered in several industrial applications for CO 2 capture and storage (CCS). An apparatus was designed and built for determining the Joule–Thomson effect. The accuracy of the device was verified by comparing the experimental data with the literature on nitrogen and carbon dioxide. New Joule–Thomson coefficient (μ JT ) measurements for three binary mixtures of (CO 2 + N 2 ) with molar compositions x N 2 = (0.05, 0.10, 0.50) were performed in the temperature range between 298.15 and 423.15 K and at pressures up to 14 MPa. Three equations of state (GERG-2008 equation, AGA8-92DC, and the Peng–Robinson) were used to calculate the μ JT compared with the corresponding experimental data. All of the equations studied here except PR have shown good prediction of μ JT for (CO 2 + N 2 ) mixtures. The relative deviations with respect to experimental data for all (CO 2 + N 2 ) mixtures from the GERG-2008 were within the ±2.5% band, and the AGA8-DC92 EoSs were within ±3%. The Joule–Thomson inversion curve (JTIC) has also been modeled by the aforementioned EoSs, and a comparison was made between the calculated JTICs and the available literature data. The GERG-2008 and AGA8-92DC EoSs show good agreement in predicting the JTIC for pure CO 2 and N 2 . The PR equation only matches well with the JTIC for pure N 2 , while it gives a poor prediction for pure CO 2 . For the (CO 2 + N 2 ) mixtures, the three equations all give similar results throughout the full span of JTICs. The temperature and pressure of the transportation and compression conditions in CCS are far lower than the corresponding predicted P inv,max and T inv,max for (CO 2 + N 2 ) mixtures.

Investigating cyclopentane hydrate nucleation and growth using microfluidics

“…CO 2 is injected under pressure and is typically stored in a liquid or supercritical state in saline aquifers [3]. In depleted reservoirs, the pressure is low and the temperature is cold, these initial conditions coupled with the thermodynamic aspects of flow in the well and perforations (Joule-Thomson effect) bring potentially the system in the CO 2 hydrates zone stability [5,6]. The formation of CO 2 hydrates at the beginning of CO 2 injection can lead to partial to complete clogging of porous rock formations where the pressure and temperature conditions are favorable for their formation [7,8].…”