Quantification of the mass transport in a two phase binary system at elevated pressures applying Raman spectroscopy: Pendant liquid solvent drop in a supercritical carbon dioxide environment

Abstract An asymmetric structure of volute in a supercritical carbon dioxide centrifugal compressor induces a non-uniform circumferential distribution of the upstream flow field, which inevitably affects the formation of a two-phase region of carbon dioxide in an impeller. In this work, unsteady simulations for centrifugal compressors were conducted. First, the influence of low static strip induced by low static pressure near volute tongue on the impeller flow field was presented. Then, the non-uniform flow field distribution in the impeller passages and flow characteristics of the passages at the impeller inlet were obtained. Finally, the two-phase regions in the impeller were presented. The results demonstrate that for a centrifugal compressor with volute, the two-phase region appears not only on the suction surface of the leading edge of the blade, but also in some impeller passages, on the pressure surface of the blade near the leading edge, and in the leading edge and mid-chord of tip clearance, under the design conditions. The low static pressure strip induced by the volute leads to a high-speed region in the impeller passages where the temperature and pressure of supercritical carbon dioxide fall below the critical point and carbon dioxide enters the two-phase region. Meanwhile, the static pressure on the blade surface is distorted under the influence of a high-speed region in the passages, resulting in the formation of a two-phase region at the tip clearance. The flow distortion of passages at the impeller inlet results in the appearance of two-phase regions on the both sides of leading edge of the blade. The dryness on the suction side of the blade leading edge and the leading edge of the tip clearance is lower, which indicated that the proportion of liquid-phase carbon dioxide is higher in these two-phase regions.

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Solubility of the Ketoconazole (an Antifungal Drug) in Supercritical Carbon Dioxide and Menthol as a Cosolvent (Ternary System): Experimental Data and Empirical Correlations

10.21203/rs.3.rs-139806/v1 ◽

2021 ◽

Author(s):

Gholamhossein Sodeifian ◽

Seyed Ali Sajadian ◽

Fariba Razmimanesh ◽

Seyed Mojtaba Hazaveie

Keyword(s):

Experimental Data ◽

Carbon Dioxide ◽

Binary System ◽

Supercritical Carbon Dioxide ◽

Ternary System ◽

Drug Solubility ◽

Analysis Method ◽

Empirical Correlations ◽

Semiempirical Models ◽

Supercritical Carbon

Abstract One of the main steps in choosing the drug nanoparticle production processes by supercritical carbon dioxide (SC-CO2) is determining the solubility of the solid solute. For this purpose, the solubility of Ketoconazole (KTZ) in the SC-CO2, binary system, as well as in the SC-CO2-menthol (cosolvent), ternary system, was measured at 308–338 K and 12–30 MPa using the static analysis method. The KTZ solubility in the SC-CO2 ranged between 1.70×10− 6 and 8.02×10− 4, while drug solubility in the SC-CO2 with cosolvent varied from 2.7×10− 5 to 1.96×10− 4. This difference indicated the significant effect of menthol cosolvent on KTZ solubility in the SC-CO2. Moreover, KTZ solubilities in the two systems were correlated by several empirical and semiempirical models. Among them, Sodeifian et al., Bian et al., MST, and Bartle et al. models can more accurately correlate experimental data for the binary system than other used models. Also, the Sodeifian and Sajadian model well fitted the solubility data of the ternary system with AARD,%= 6.45, Radj= 0.995.

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Characterization of Supercritical Carbon Dioxide Transport within a Brine-Filled Porous Media Using a Two-Phase Pore Network Model

ECS Meeting Abstracts ◽

10.1149/ma2011-01/29/1639 ◽

2011 ◽

Keyword(s):

Carbon Dioxide ◽

Porous Media ◽

Supercritical Carbon Dioxide ◽

Network Model ◽

Pore Network ◽

Pore Network Model ◽

Two Phase ◽

Carbon Dioxide Transport ◽

Supercritical Carbon

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Visualization of Supercritical Carbon Dioxide Flow Through a Converging-Diverging Nozzle

Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy ◽

10.1115/gt2019-91691 ◽

2019 ◽

Author(s):

Chang Hyeon Lim ◽

Gokul Pathikonda ◽

Sandeep Pidaparti ◽

Devesh Ranjan

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Critical Point ◽

High Speed ◽

Operating Conditions ◽

Higher Plant ◽

Two Phase ◽

Pressure Profiles ◽

Flow Through ◽

Supercritical Carbon

Abstract Supercritical carbon dioxide (sCO2) power cycles have the potential to offer a higher plant efficiency than the traditional Rankine superheated/supercritical steam cycle or Helium Brayton cycles. The most attractive characteristic of sCO2 is that the fluid density is high near the critical point, allowing compressors to consume less power than conventional gas Brayton cycles and maintain a smaller turbomachinery size. Despite these advantages, there still exist unsolved challenges in design and operation of sCO2 compressors near the critical point. Drastic changes in fluid properties near the critical point and the high compressibility of the fluid pose several challenges. Operating a sCO2 compressor near the critical point has potential to produce two phase flow, which can be detrimental to turbomachinery performance. To mimic the expanding regions of compressor blades, flow through a converging-diverging nozzle is investigated. Pressure profiles along the nozzle are recorded and presented for operating conditions near the critical point. Using high speed shadowgraph images, onset and growth of condensation is captured along the nozzle. Pressure profiles were calculated using a one-dimensional homogeneous equilibrium model and compared with experimental data.

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Analysis of the Solubility of TNT and RDX in TNT/RDX/SC-CO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.940.37 ◽

2014 ◽

Vol 940 ◽

pp. 37-40

Author(s):

Wen Su Ji ◽

Yu Kui Ding ◽

Yu Qiu Xu

Keyword(s):

Carbon Dioxide ◽

Binary System ◽

Supercritical Carbon Dioxide ◽

Ternary System ◽

Pressure Range ◽

Turning Point ◽

Support Effect ◽

Extraction Temperature ◽

Supercritical Carbon

The solubility of TNT and RDX was measured in supercritical carbon dioxide fluid at 303.0, 308.0, 323.0, 338.0 K, and over the pressure range from 10.0 MPa to 50.0 MPa. This study examined the influences of extraction temperature, extraction pressure and support effect (SE) between molecules of TNT and RDX on their solubility in the TNT/RDX/SC-CO2 system. The results show that solubility of TNT and RDX in TNT/RDX/SC-CO2 ternary system is much higher than that in binary system. The values of SE of RDX and TNT increase first and decrease then with the pressure changing. The pressure turning point occurred over the pressure range from 25 MPa to 28 MPa for TNT and from 13 MPa to 20 MPa for RDX.

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