Exergetic Analysis of a Cryogenic Air Separation Unit
This case study analyzes a cryogenic air separation unit (ASU) with a production of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mover accent="true"><mi>V</mi>&l...
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| Format: | Article |
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MDPI AG
2022-02-01
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| Series: | Entropy |
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| Online Access: | https://www.mdpi.com/1099-4300/24/2/272 |
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| author | Sorin Bucsa Alexandru Serban Mugur C. Balan Claudia Ionita Gabriel Nastase Catalina Dobre Alexandru Dobrovicescu |
| author_facet | Sorin Bucsa Alexandru Serban Mugur C. Balan Claudia Ionita Gabriel Nastase Catalina Dobre Alexandru Dobrovicescu |
| author_sort | Sorin Bucsa |
| collection | DOAJ |
| description | This case study analyzes a cryogenic air separation unit (ASU) with a production of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mover accent="true"><mi>V</mi><mo>˙</mo></mover><mrow><msub><mi>O</mi><mn>2</mn></msub></mrow></msub><mo>=</mo><mn>58,300</mn><mo> </mo><mrow><mo>[</mo><mrow><mfrac><mrow><msup><mi>m</mi><mn>3</mn></msup><mi>N</mi></mrow><mi>h</mi></mfrac></mrow><mo>]</mo></mrow></mrow></semantics></math></inline-formula> of gaseous oxygen with a concentration greater than 98.5%, operating in Romania on a steel plant platform. The goal of the paper is to provide an extensive model of exergetic analysis that could be used in an optimization procedure when decisional parameters are changed or structural design modifications are implemented. For each key part of the Air Separation Unit, an exergetic product and fuel were defined and, based on their definition, the coefficient of performance of each functional zone was calculated. The information about the magnitude of the exergetic losses offers solutions for their future recovery. The analysis of the exergy destructions suggests when it is worth making a larger investment. The exergetic analysis of the compression area of the ASU points out an exergy destruction and loss of 37% from the total plant’s electrical energy input. The exergy loss with the heat transferred to the cooling system of compressors can be recovered; for the exergy destruction portion, the challenge between investment and operating costs should be considered. The exergy destruction of the air separation columns found the High Pressure Column (HPC) to be more destructive than the Low Pressure Column. The share of the exergy destruction in the total plant’s electrical energy input is 8.3% for the HPC. The local COP of the HPC, calculated depending on the total exergy of the local product and fuel, is 62.66%. The calculus of the air separation column is performed with the ChemSep simulator. |
| first_indexed | 2024-03-09T22:01:25Z |
| format | Article |
| id | doaj.art-431650001c984095a182818899bd053f |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-03-09T22:01:25Z |
| publishDate | 2022-02-01 |
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| record_format | Article |
| series | Entropy |
| spelling | doaj.art-431650001c984095a182818899bd053f2023-11-23T19:48:42ZengMDPI AGEntropy1099-43002022-02-0124227210.3390/e24020272Exergetic Analysis of a Cryogenic Air Separation UnitSorin Bucsa0Alexandru Serban1Mugur C. Balan2Claudia Ionita3Gabriel Nastase4Catalina Dobre5Alexandru Dobrovicescu6Department of Engineering Thermodynamics, University Politehnica of Bucharest, 060042 Bucharest, RomaniaDepartment of Engineering Thermodynamics, University Politehnica of Bucharest, 060042 Bucharest, RomaniaDepartment of Thermodynamics, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, RomaniaDepartment of Engineering Thermodynamics, University Politehnica of Bucharest, 060042 Bucharest, RomaniaDepartment of Engineering Thermodynamics, University Politehnica of Bucharest, 060042 Bucharest, RomaniaDepartment of Engineering Thermodynamics, University Politehnica of Bucharest, 060042 Bucharest, RomaniaDepartment of Engineering Thermodynamics, University Politehnica of Bucharest, 060042 Bucharest, RomaniaThis case study analyzes a cryogenic air separation unit (ASU) with a production of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mover accent="true"><mi>V</mi><mo>˙</mo></mover><mrow><msub><mi>O</mi><mn>2</mn></msub></mrow></msub><mo>=</mo><mn>58,300</mn><mo> </mo><mrow><mo>[</mo><mrow><mfrac><mrow><msup><mi>m</mi><mn>3</mn></msup><mi>N</mi></mrow><mi>h</mi></mfrac></mrow><mo>]</mo></mrow></mrow></semantics></math></inline-formula> of gaseous oxygen with a concentration greater than 98.5%, operating in Romania on a steel plant platform. The goal of the paper is to provide an extensive model of exergetic analysis that could be used in an optimization procedure when decisional parameters are changed or structural design modifications are implemented. For each key part of the Air Separation Unit, an exergetic product and fuel were defined and, based on their definition, the coefficient of performance of each functional zone was calculated. The information about the magnitude of the exergetic losses offers solutions for their future recovery. The analysis of the exergy destructions suggests when it is worth making a larger investment. The exergetic analysis of the compression area of the ASU points out an exergy destruction and loss of 37% from the total plant’s electrical energy input. The exergy loss with the heat transferred to the cooling system of compressors can be recovered; for the exergy destruction portion, the challenge between investment and operating costs should be considered. The exergy destruction of the air separation columns found the High Pressure Column (HPC) to be more destructive than the Low Pressure Column. The share of the exergy destruction in the total plant’s electrical energy input is 8.3% for the HPC. The local COP of the HPC, calculated depending on the total exergy of the local product and fuel, is 62.66%. The calculus of the air separation column is performed with the ChemSep simulator.https://www.mdpi.com/1099-4300/24/2/272chemical exergyrectification columncompression unit |
| spellingShingle | Sorin Bucsa Alexandru Serban Mugur C. Balan Claudia Ionita Gabriel Nastase Catalina Dobre Alexandru Dobrovicescu Exergetic Analysis of a Cryogenic Air Separation Unit Entropy chemical exergy rectification column compression unit |
| title | Exergetic Analysis of a Cryogenic Air Separation Unit |
| title_full | Exergetic Analysis of a Cryogenic Air Separation Unit |
| title_fullStr | Exergetic Analysis of a Cryogenic Air Separation Unit |
| title_full_unstemmed | Exergetic Analysis of a Cryogenic Air Separation Unit |
| title_short | Exergetic Analysis of a Cryogenic Air Separation Unit |
| title_sort | exergetic analysis of a cryogenic air separation unit |
| topic | chemical exergy rectification column compression unit |
| url | https://www.mdpi.com/1099-4300/24/2/272 |
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