Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate
Carbon capture and utilization can mitigate the problems caused by CO2 emissions, at the same time that valuable products are obtained from the conversion of CO2. By reduction of CO2 in hydrothermal conditions (T = 275°C, P = 200 bar), high yields of conversion of CO2 to formate of up to 70% can be...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Elsevier
2022-11-01
|
Series: | Energy Reports |
Subjects: | |
Online Access: | http://www.sciencedirect.com/science/article/pii/S2352484722017899 |
_version_ | 1797901849824591872 |
---|---|
author | Laura Quintana-Gómez José J. Segovia Ángel Martín M. Dolores Bermejo |
author_facet | Laura Quintana-Gómez José J. Segovia Ángel Martín M. Dolores Bermejo |
author_sort | Laura Quintana-Gómez |
collection | DOAJ |
description | Carbon capture and utilization can mitigate the problems caused by CO2 emissions, at the same time that valuable products are obtained from the conversion of CO2. By reduction of CO2 in hydrothermal conditions (T = 275°C, P = 200 bar), high yields of conversion of CO2 to formate of up to 70% can be achieved in reaction times of 1 h. This technology can be implemented as a continuous process in large CO2 production sites, and for this purpose the energy optimization of the process is essential to make it technically and economically feasible. Therefore, the objective of this work is to evaluate the thermodynamic efficiency and the cost of the different units involved in the hydrothermal conversion of CO2 into formate. Exergy balances were applied to the main units of a continuous plant for the hydrothermal reduction of CO2 into formate. The exergy efficiency, exergy improvement potential rate, the exergoeconomic costs and the sustainability index were calculated along with the exergy destruction rate in the main process units. The specific exergy destroyed per kg of formate produced was calculated as 6260 kJ/kg. The results showed that the major exergy destruction rate took place in the reactor, representing the 69% of the total exergy destruction in the plant. Although this destruction rate increased with the conversion in the reactor, in terms of the overall efficiency and exergetic cost of the process, a high conversion above 70% is advisable. The exergetic efficiency of each unit was also evaluated along with the exergetic improvement potential rate. The lowest efficiency was identified in the pump with a value of 0.44. In the case of the exergoeconomic performance, the reactor showed the highest cost rate representing the 67% of the total costs. The total exergoeconomic cost rate was 2.3 €/kg of formate produced. |
first_indexed | 2024-04-10T09:08:27Z |
format | Article |
id | doaj.art-17e343ec7fc24514b2f94e0cef1a59d2 |
institution | Directory Open Access Journal |
issn | 2352-4847 |
language | English |
last_indexed | 2024-04-10T09:08:27Z |
publishDate | 2022-11-01 |
publisher | Elsevier |
record_format | Article |
series | Energy Reports |
spelling | doaj.art-17e343ec7fc24514b2f94e0cef1a59d22023-02-21T05:13:34ZengElsevierEnergy Reports2352-48472022-11-0181234812356Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formateLaura Quintana-Gómez0José J. Segovia1Ángel Martín2M. Dolores Bermejo3BioEcoUva. Research Institute on Bioeconomy, PressTech Group, Department of Chemical Engineering and Environmental Technology, Universidad de Valladolid, Doctor Mergelina s/n, 47011, Valladolid, SpainBioEcoUva. Research Institute on Bioeconomy, Laboratory of Thermodynamic and Calibration TERMOCAL, Department of Energy and Fluid Mechanics Engineering, Universidad de Valladolid, Paseo de Belén s/n, 47011, Valladolid, SpainBioEcoUva. Research Institute on Bioeconomy, PressTech Group, Department of Chemical Engineering and Environmental Technology, Universidad de Valladolid, Doctor Mergelina s/n, 47011, Valladolid, Spain; Corresponding author.BioEcoUva. Research Institute on Bioeconomy, PressTech Group, Department of Chemical Engineering and Environmental Technology, Universidad de Valladolid, Doctor Mergelina s/n, 47011, Valladolid, SpainCarbon capture and utilization can mitigate the problems caused by CO2 emissions, at the same time that valuable products are obtained from the conversion of CO2. By reduction of CO2 in hydrothermal conditions (T = 275°C, P = 200 bar), high yields of conversion of CO2 to formate of up to 70% can be achieved in reaction times of 1 h. This technology can be implemented as a continuous process in large CO2 production sites, and for this purpose the energy optimization of the process is essential to make it technically and economically feasible. Therefore, the objective of this work is to evaluate the thermodynamic efficiency and the cost of the different units involved in the hydrothermal conversion of CO2 into formate. Exergy balances were applied to the main units of a continuous plant for the hydrothermal reduction of CO2 into formate. The exergy efficiency, exergy improvement potential rate, the exergoeconomic costs and the sustainability index were calculated along with the exergy destruction rate in the main process units. The specific exergy destroyed per kg of formate produced was calculated as 6260 kJ/kg. The results showed that the major exergy destruction rate took place in the reactor, representing the 69% of the total exergy destruction in the plant. Although this destruction rate increased with the conversion in the reactor, in terms of the overall efficiency and exergetic cost of the process, a high conversion above 70% is advisable. The exergetic efficiency of each unit was also evaluated along with the exergetic improvement potential rate. The lowest efficiency was identified in the pump with a value of 0.44. In the case of the exergoeconomic performance, the reactor showed the highest cost rate representing the 67% of the total costs. The total exergoeconomic cost rate was 2.3 €/kg of formate produced.http://www.sciencedirect.com/science/article/pii/S2352484722017899CO2 utilizationExergy analysisExergy destructionExergoeconomic analysis |
spellingShingle | Laura Quintana-Gómez José J. Segovia Ángel Martín M. Dolores Bermejo Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate Energy Reports CO2 utilization Exergy analysis Exergy destruction Exergoeconomic analysis |
title | Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate |
title_full | Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate |
title_fullStr | Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate |
title_full_unstemmed | Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate |
title_short | Exergetic analysis of a continuous plant for the hydrothermal reduction of CO2 into formate |
title_sort | exergetic analysis of a continuous plant for the hydrothermal reduction of co2 into formate |
topic | CO2 utilization Exergy analysis Exergy destruction Exergoeconomic analysis |
url | http://www.sciencedirect.com/science/article/pii/S2352484722017899 |
work_keys_str_mv | AT lauraquintanagomez exergeticanalysisofacontinuousplantforthehydrothermalreductionofco2intoformate AT josejsegovia exergeticanalysisofacontinuousplantforthehydrothermalreductionofco2intoformate AT angelmartin exergeticanalysisofacontinuousplantforthehydrothermalreductionofco2intoformate AT mdoloresbermejo exergeticanalysisofacontinuousplantforthehydrothermalreductionofco2intoformate |