CO2 gas absorption by CH3OH based nanofluids in an annular contactor at low rotational speeds

Pineda, Israel Torres,Choi, Chang Kyoung,Kang, Yong Tae Elsevier 2014 INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL Vol.23 No.-

<P>In this work, carbon dioxide (CO2) absorption experiments are performed in a custom designed vertical annular contactor (AC) at low rotational speeds. Methanol is used as solvent and Al2O3, SiO2 and TiO2 nanoparticles are combined with the methanol to produce nanofluids. The AC performance is compared to that of a modified version in which trays are added to enhance the CO2 absorption rate (T-AC). Experiments in co-current and counter-current flows are carried out. In addition, two-phase flow patterns in the AC and in the modified version are analyzed by using a high speed visualization system. The results show no effect on the absorption rate for pure methanol at Re-omega < 17,000. In the counter-current flow, however, nanofluids show a better performance in the AC with maximum enhancements of 4.6% for TiO2, 1.2% for Al2O3 and 1.1% for SiO2 compared to pure methanol. The addition of trays enhances the CO2 absorption rate up to 9%, 10%, 6% and 5% for pure methanol, Al2O3, SiO2, and TiO2, respectively for the counter-current flow. Likewise, the highest rotation effectiveness is found in the T-AC for Al(2)O(3)and TiO2 with 24.2% and 14.4%, respectively. (C) 2014 Elsevier Ltd. All rights reserved.</P>

CO₂ absorption enhancement by nanoabsorbents in Taylor-Couette absorber

Torres Pineda, I.,Kang, Y.T. Pergamon Press ; Elsevier Science Ltd 2016 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.100 No.-

CO<SUB>2</SUB> gas is physically absorbed in liquid methanol in bubbly Taylor-Couette absorber. The experiments are performed in the turbulent regime with rotational Reynolds numbers ranging from 1.9x10<SUP>4</SUP> to 19.2x10<SUP>4</SUP>. The volumetric mass transfer coefficients are obtained for the counter-current operation. Methanol is utilized as the base absorbent. In addition, with the purpose of enhancing CO<SUB>2</SUB> absorption performance, Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles are combined with methanol to produce the absorbent. The results show an increase in the volumetric mass transfer coefficient that reaches a maximum value at 4x10<SUP>4</SUP> rotational Reynolds number for both pure methanol and the nanoabsorbents, after which the absorption rate declines almost linearly with the rotational speed. The reasons for the reduction in the absorption performance are discussed. The maximum enhancement in the volumetric mass transfer coefficient is estimated at 20% for 4x10<SUP>4</SUP> rotational Reynolds number and up to 27% for methanol and Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles at a concentration of 0.1vol%.

Mass transfer analysis for CO₂ bubble absorption in methanol/Al₂O₃ nanoabsorbents

Torres Pineda, Israel,Kim, Dongmin,Kang, Yong Tae Elsevier 2017 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.114 No.-

<P><B>Abstract</B></P> <P>In this paper computational fluid dynamics (CFD) analysis is carried out to investigate CO<SUB>2</SUB> bubble absorption characteristics in methanol/Al₂O<SUB>3</SUB> nanoabsorbents. Bubble size, rising velocity and mass transfer rate are compared to the previous experimental results for validation. It is found that the distance traveled for each CO<SUB>2</SUB> bubble increases as the concentration of Al<SUB>2</SUB>O<SUB>3</SUB> increases, which, in consequence, increases the residence time between liquid and gas phases resulting in higher interfacial mass transfer rates. For the case of a bubble rising in the gap between walls, the wall shear stress has a major effect on the bubble diameter and rising velocity which in consequence affects the mass transfer coefficient. It is concluded that the mass transfer coefficient enhances by about 40% by adding Al₂O<SUB>3</SUB> nanoparticles (0.01vol%) compared with pure methanol absorbent from the experimental and simulation results. It is also concluded that the use of nanoparticles has a higher impact on mass transfer rate than it does on mass transfer amount, which depends on the residence time and travel distance of CO<SUB>2</SUB> bubbles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Mass transfer analysis is carried out for CO<SUB>2</SUB> bubble absorption in nanoabsorbents. </LI> <LI> CO<SUB>2</SUB> absorption enhancement by nanoabsorbents is evaluated. </LI> <LI> Mass transfer coefficient enhances by about 40% by adding Al₂O<SUB>3</SUB> nanoparticles (0.01vol%). </LI> <LI> The use of nanoparticles has a higher impact on mass transfer rate than it does on mass transfer amount. </LI> </UL> </P>

CO₂ ABSORPTION ENHANCEMENT USING METHANOL-BASED NANOFLUIDS

Israel Torres Pineda,Jung-Yeul Jung(정정열),Yong Tae Kang(강용태) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

Recently there are growing concerns that anthropogenic carbon dioxide (CO₂) emissions cause the global warming problem. In this study, the suspensions of Al₂O₃ nanoparticles in methanol (called the nanofluid) are developed and estimated to apply it to absorb the CO₂ in AGR (acid gas removal) system. The continuous removal system is an acrylic tray column with nine plates. The column is a sieve tray type which has flat perforated plates where the vapor velocity keeps the liquid from flowing down through the holes. The absorption experiments have been carried out employing a tray column, where the CO₂ gas and methanol liquid are counter-current flow. The test section is equipped with two mass flow meters to measure the absorption rate. We obtained an enhanced absorption rate (compared to pure methanol absorbent) of 26.9%, 101.3% and 251.5% for the concentrations of 0.005, 0.01 and 0.05vol% respectively.

CO2 Absorption in Methanol-based AI2O3 and SiO2 Nanofluids

( Israel Torres Pineda ),( Jae Won Lee ),( Yong Tae Kang ) 한국액체미립화학회 2011 한국액체미립화학회 학술강연회 논문집 Vol.2011 No.-

CO₂ absorption in methanol-based Al₂O₃ and SiO₂ nanofluids in a continuous removal system

Israel Torres Pineda,Jae Won Lee,Yong Tae Kang 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10

The purpose of this study to enhance the absorption process of CO<SUB>2</SUB> in methanol by the addition of Al<SUB>2</SUB>O<SUB>3</SUB> and SiO<SUB>2</SUB> nanoparticles. The continuous removal system is an acrylic tray column with twelve plate where the CO<SUB>2</SUB> gas and methanol liquid are brought in contact in a counter-current flow. The test section is equipped with two mass flow meters to measure the absorption rate. It is found a maximum enhanced absorption rate (compared to pure methanol absorbent) of 9% for both particles.

L1599B: CLOUD ENVELOPE AND C⁺EMISSION IN A REGION OF MODERATELY ENHANCED RADIATION FIELD

Goldsmith, Paul F.,Pineda, Jorge L.,Langer, William D.,Liu, Tie,Requena-Torres, Miguel,Ricken, Oliver,Riquelme, Denise American Astronomical Society 2016 The Astrophysical journal Vol.824 No.2

<P>We study the effects of an asymmetric radiation field on the properties of a molecular cloud envelope. We employ observations of carbon monoxide ((CO)-C-12 and (CO)-C-13), atomic carbon, ionized carbon, and atomic hydrogen to analyze the chemical and physical properties of the core and envelope of L1599B, a molecular cloud forming a portion of the ring at similar or equal to 27 pc from the star A Ori. The 08 star provides an asymmetric radiation field that produces a moderate enhancement of the external radiation field. Observations of the [C II] fine structure line with the GREAT instrument on SOFIA indicate a significant enhanced emission on the side of the cloud facing the star, while the [C (CO)-C-12 and (CO)-C-13 J = 1-0 and 2-1, and (CO)-C-12 J = 3-2 data from the Purple Mountain Observatory and APEX telescopes suggest a relatively typical cloud interior. The atomic, ionic, and molecular line centroid velocities track each other very closely, and indicate that the cloud may be undergoing differential radial motion. The Hi data from the Arecibo GALFA survey and the SOFIA/GREAT [C II] data do not suggest any systematic motion of the halo gas, relative to the dense central portion of the cloud traced by (CO)-C-12 and (CO)-C-13.</P>

Combined CO₂ absorption/regeneration performance enhancement by using nanoabsorbents

Lee, Jae Won,Torres Pineda, Israel,Lee, Jung Hun,Kang, Yong Tae Elsevier 2016 APPLIED ENERGY Vol.178 No.-

<P>The reduction of in the emissions of CO2, which is the representative greenhouse gas, is actively investigated worldwide because of its contribution to global warming. Energy generation processes involving the gasification of fossil fuels separate the constituent gases before combustion occurs, rendering the capture of CO2 more attainable. Generally, CO2 is captured through an absorption method by using a liquid absorbent in large scale gasification systems. According to Henry's solubility law, the absorption and regeneration processes should be operated at low and high temperatures respectively, and these require high energy consumption. As a solution, nanoparticles are added to the absorbent (methanol) to reduce energy consumption required in the absorption and regeneration processes. In this study, the absorption/regeneration performance was evaluated through a lab-scale combined CO2-absorption/regeneration system. The nanoparticles used are SiO2 and Al2O3, which are added at a 0.01 vol% concentration. In the case of the Al2O3/methanol nanoabsorbent, the performance decreases as the number of cycle increases, whereas the performance is improved steadily in the case of the SiO2/methanol nanoabsorbent. Thus, the SiO2 nanoparticles are more suitable for the combined CO2 absorption/regeneration process. Furthermore, the mass transfer enhancement mechanisms of the absorption/regeneration process according to the addition of nanoparticles are presented. (C) 2016 Elsevier Ltd. All rights reserved.</P>

메탄올 나노유체를 이용한 CO2 흡수 성능 향상

이재원(Jae Won Lee),Israel Torres Pineda,정정열(Jung-Yeul Jung),강용태(Yong Tae Kang) 대한설비공학회 2012 대한설비공학회 학술발표대회논문집 Vol.2012 No.6

In this study, nanoparticles and methanol are combined into the methanol nanofluid to enhance the CO2 absorption rate of the base fluid which is pure methanol. The absorption experiments are performed in both the bubble type absorber and the tray column systems. The maximum CO2 absorption enhancement of the nanofluids compared to the base fluid was obtained ~8.9% at 0.05 vol% of SiO2/methanol nanofluids at the tray column absortpion system. The methanol nanofluids are expected to be a promising candidate for removing the acid gases such as CO2 and H2S

나는 유체를 이용한 이산화탄소 흡수 향상 연구

이재원 ( Jae Won Lee ),이스라엘 ( Israel ),토레스 ( Torres ),피네다 ( Pineda ),강용태 ( Yong Tae Kang ) 한국액체미립화학회 2014 한국액체미립화학회 학술강연회 논문집 Vol.2014 No.-

CO2 absorption experiments are performed with two different devices: a tray column and an annular contactor that rotates at different speeds. Al2O3 nanoparticles are suspended in methanol to produce nanofluids with the purpose of enhancing the absorption rate of the CO2 gas into the absorbent. The experimental system has a mass flow controller at the inlet and a mass flow meter at the outlet to measure the absorption rate in the continuous system.