Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems
In this paper, we analyze the autothermal reforming (ATR) of methane through Gibbs energy minimization and entropy maximization methods to analyze isothermic and adiabatic systems, respectively. The software GAMS<sup>®</sup> 23.9 and the CONOPT3 solver were used to conduct the simulation...
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| Format: | Article |
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MDPI AG
2023-10-01
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| Series: | Methane |
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| Online Access: | https://www.mdpi.com/2674-0389/2/4/26 |
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| author | Matheus Henrique Silva Cavalcante Ícaro Augusto Maccari Zelioli Emílio Émerson Xavier Guimarães Filho Julles Mitoura dos Santos Júnior Annamaria Dória Souza Vidotti Antonio Carlos Daltro de Freitas Reginaldo Guirardello |
| author_facet | Matheus Henrique Silva Cavalcante Ícaro Augusto Maccari Zelioli Emílio Émerson Xavier Guimarães Filho Julles Mitoura dos Santos Júnior Annamaria Dória Souza Vidotti Antonio Carlos Daltro de Freitas Reginaldo Guirardello |
| author_sort | Matheus Henrique Silva Cavalcante |
| collection | DOAJ |
| description | In this paper, we analyze the autothermal reforming (ATR) of methane through Gibbs energy minimization and entropy maximization methods to analyze isothermic and adiabatic systems, respectively. The software GAMS<sup>®</sup> 23.9 and the CONOPT3 solver were used to conduct the simulations and thermodynamic analyses in order to determine the equilibrium compositions and equilibrium temperatures of this system. Simulations were performed covering different pressures in the range of 1 to 10 atm, temperatures between 873 and 1073 K, steam/methane ratio was varied in the range of 1.0/1.0 and 2.0/1.0 and oxygen/methane ratios in the feed stream, in the range of 0.5/1.0 to 2.0/1.0. The effect of using pure oxygen or air as oxidizer agent to perform the reaction was also studied. The simulations were carried out in order to maintain the same molar proportions of oxygen as in the simulated cases considering pure oxygen in the reactor feed. The results showed that the formation of hydrogen and synthesis gas increased with temperature, average composition of 71.9% and 56.0% using air and O<sub>2</sub>, respectively. These results are observed at low molar oxygen ratios (O<sub>2</sub>/CH<sub>4</sub> = 0.5) in the feed. Higher pressures reduced the production of hydrogen and synthesis gas produced during ATR of methane. In general, reductions on the order of 19.7% using O<sub>2</sub> and 14.0% using air were observed. It was also verified that the process has autothermicity in all conditions tested and the use of air in relation to pure oxygen favored the compounds of interest, mainly in conditions of higher pressure (10 atm). The mean reductions with increasing temperature in the percentage increase of H<sub>2</sub> and syngas using air under 1.5 and 10 atm, at the different O<sub>2</sub>/CH<sub>4</sub> ratios, were 5.3%, 13.8% and 16.5%, respectively. In the same order, these values with the increase of oxygen were 3.6%, 6.4% and 9.1%. The better conditions for the reaction include high temperatures, low pressures and low O<sub>2</sub>/CH<sub>4</sub> ratios, a region in which there is no swelling in terms of the oxygen source used. In addition, with the introduction of air, the final temperature of the system was reduced by 5%, which can help to reduce the negative impacts of high temperatures in reactors during ATR reactions. |
| first_indexed | 2024-03-08T20:32:18Z |
| format | Article |
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| issn | 2674-0389 |
| language | English |
| last_indexed | 2024-03-08T20:32:18Z |
| publishDate | 2023-10-01 |
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| series | Methane |
| spelling | doaj.art-c79182d3fc8c42e0b4eea9fedd0ecc6c2023-12-22T14:24:56ZengMDPI AGMethane2674-03892023-10-012438940310.3390/methane2040026Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic SystemsMatheus Henrique Silva Cavalcante0Ícaro Augusto Maccari Zelioli1Emílio Émerson Xavier Guimarães Filho2Julles Mitoura dos Santos Júnior3Annamaria Dória Souza Vidotti4Antonio Carlos Daltro de Freitas5Reginaldo Guirardello6Engineering Department, Exact Sciences and Technology Center, Federal University of Maranhão (UFMA), Av. dos Portugueses, 1966, Bacanga, São Luís 65080-805, MA, BrazilSchool of Chemical Engineering, University of Campinas (UNICAMP), Av. Albert Einstein 500, Campinas 13083-852, SP, BrazilSchool of Chemical Engineering, University of Campinas (UNICAMP), Av. Albert Einstein 500, Campinas 13083-852, SP, BrazilSchool of Chemical Engineering, University of Campinas (UNICAMP), Av. Albert Einstein 500, Campinas 13083-852, SP, BrazilEngineering Department, Exact Sciences and Technology Center, Federal University of Maranhão (UFMA), Av. dos Portugueses, 1966, Bacanga, São Luís 65080-805, MA, BrazilEngineering Department, Exact Sciences and Technology Center, Federal University of Maranhão (UFMA), Av. dos Portugueses, 1966, Bacanga, São Luís 65080-805, MA, BrazilSchool of Chemical Engineering, University of Campinas (UNICAMP), Av. Albert Einstein 500, Campinas 13083-852, SP, BrazilIn this paper, we analyze the autothermal reforming (ATR) of methane through Gibbs energy minimization and entropy maximization methods to analyze isothermic and adiabatic systems, respectively. The software GAMS<sup>®</sup> 23.9 and the CONOPT3 solver were used to conduct the simulations and thermodynamic analyses in order to determine the equilibrium compositions and equilibrium temperatures of this system. Simulations were performed covering different pressures in the range of 1 to 10 atm, temperatures between 873 and 1073 K, steam/methane ratio was varied in the range of 1.0/1.0 and 2.0/1.0 and oxygen/methane ratios in the feed stream, in the range of 0.5/1.0 to 2.0/1.0. The effect of using pure oxygen or air as oxidizer agent to perform the reaction was also studied. The simulations were carried out in order to maintain the same molar proportions of oxygen as in the simulated cases considering pure oxygen in the reactor feed. The results showed that the formation of hydrogen and synthesis gas increased with temperature, average composition of 71.9% and 56.0% using air and O<sub>2</sub>, respectively. These results are observed at low molar oxygen ratios (O<sub>2</sub>/CH<sub>4</sub> = 0.5) in the feed. Higher pressures reduced the production of hydrogen and synthesis gas produced during ATR of methane. In general, reductions on the order of 19.7% using O<sub>2</sub> and 14.0% using air were observed. It was also verified that the process has autothermicity in all conditions tested and the use of air in relation to pure oxygen favored the compounds of interest, mainly in conditions of higher pressure (10 atm). The mean reductions with increasing temperature in the percentage increase of H<sub>2</sub> and syngas using air under 1.5 and 10 atm, at the different O<sub>2</sub>/CH<sub>4</sub> ratios, were 5.3%, 13.8% and 16.5%, respectively. In the same order, these values with the increase of oxygen were 3.6%, 6.4% and 9.1%. The better conditions for the reaction include high temperatures, low pressures and low O<sub>2</sub>/CH<sub>4</sub> ratios, a region in which there is no swelling in terms of the oxygen source used. In addition, with the introduction of air, the final temperature of the system was reduced by 5%, which can help to reduce the negative impacts of high temperatures in reactors during ATR reactions.https://www.mdpi.com/2674-0389/2/4/26autothermal reforming of methaneGibbs energy minimizationentropy maximization |
| spellingShingle | Matheus Henrique Silva Cavalcante Ícaro Augusto Maccari Zelioli Emílio Émerson Xavier Guimarães Filho Julles Mitoura dos Santos Júnior Annamaria Dória Souza Vidotti Antonio Carlos Daltro de Freitas Reginaldo Guirardello Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems Methane autothermal reforming of methane Gibbs energy minimization entropy maximization |
| title | Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems |
| title_full | Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems |
| title_fullStr | Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems |
| title_full_unstemmed | Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems |
| title_short | Autothermal Reforming of Methane: A Thermodynamic Study on the Use of Air and Pure Oxygen as Oxidizing Agents in Isothermal and Adiabatic Systems |
| title_sort | autothermal reforming of methane a thermodynamic study on the use of air and pure oxygen as oxidizing agents in isothermal and adiabatic systems |
| topic | autothermal reforming of methane Gibbs energy minimization entropy maximization |
| url | https://www.mdpi.com/2674-0389/2/4/26 |
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