Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed
Coal--CO[subscript 2] slurry feed has been suggested as an attractive alternative to coal–water slurry feed for single-stage, entrained-flow gasifiers. Previous work demonstrated the system-level advantages of gasification-based plants equipped with CO[subscript 2] capture and CO[subscript 2] slurry...
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| Format: | Article |
| Language: | en_US |
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Elsevier
2016
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| Online Access: | http://hdl.handle.net/1721.1/104643 https://orcid.org/0000-0001-9078-8484 https://orcid.org/0000-0001-8730-272X |
| _version_ | 1826201032710946816 |
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| author | Botero, Cristina Field, Randall Ghoniem, Ahmed F Herzog, Howard J. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Botero, Cristina Field, Randall Ghoniem, Ahmed F Herzog, Howard J. |
| author_sort | Botero, Cristina |
| collection | MIT |
| description | Coal--CO[subscript 2] slurry feed has been suggested as an attractive alternative to coal–water slurry feed for single-stage, entrained-flow gasifiers. Previous work demonstrated the system-level advantages of gasification-based plants equipped with CO[subscript 2] capture and CO[subscript 2] slurry feed, under the assumption that carbon conversion remains unchanged. However, gasification in carbon dioxide has been observed to be slower than that in steam. In view of this, the impact of CO[subscript 2] slurry feeding on gasification kinetics and ultimately on carbon conversion and oxygen consumption in a pressurized, single-stage entrained-flow gasifier processing bituminous coal is studied here using a 1-D reduced order model. Results show that the CO[subscript 2] gasification reaction plays a dominant role in char conversion when the feeding system is CO[subscript 2] slurry, increasing the CO content in the products by up to a factor of two. CO inhibition of the gasification reaction and a higher degree of internal mass transport limitations lead to an up to 60% slower gasification rate, when compared to a system based on coal-water slurry. Accordingly, a gasifier with CO[subscript 2] slurry feed has 15% less oxygen consumption but a 7%-point lower carbon conversion for a given reactor outlet temperature. The gasifier outlet temperature must be raised by 90 K in order to achieve the same conversion as in a water slurry-fed reactor; the peak reactor temperature increases by 220 K as a result. Net oxygen savings of 8% are estimated for a system with a CO[subscript 2] slurry-fed gasifier relative to one with water slurry and the same level of conversion. |
| first_indexed | 2024-09-23T11:45:36Z |
| format | Article |
| id | mit-1721.1/104643 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:45:36Z |
| publishDate | 2016 |
| publisher | Elsevier |
| record_format | dspace |
| spelling | mit-1721.1/1046432024-03-23T02:15:27Z Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed Botero, Cristina Field, Randall Ghoniem, Ahmed F Herzog, Howard J. Massachusetts Institute of Technology. Department of Mechanical Engineering MIT Energy Initiative Botero, Cristina Field, Randall Herzog, Howard J Ghoniem, Ahmed F Coal--CO[subscript 2] slurry feed has been suggested as an attractive alternative to coal–water slurry feed for single-stage, entrained-flow gasifiers. Previous work demonstrated the system-level advantages of gasification-based plants equipped with CO[subscript 2] capture and CO[subscript 2] slurry feed, under the assumption that carbon conversion remains unchanged. However, gasification in carbon dioxide has been observed to be slower than that in steam. In view of this, the impact of CO[subscript 2] slurry feeding on gasification kinetics and ultimately on carbon conversion and oxygen consumption in a pressurized, single-stage entrained-flow gasifier processing bituminous coal is studied here using a 1-D reduced order model. Results show that the CO[subscript 2] gasification reaction plays a dominant role in char conversion when the feeding system is CO[subscript 2] slurry, increasing the CO content in the products by up to a factor of two. CO inhibition of the gasification reaction and a higher degree of internal mass transport limitations lead to an up to 60% slower gasification rate, when compared to a system based on coal-water slurry. Accordingly, a gasifier with CO[subscript 2] slurry feed has 15% less oxygen consumption but a 7%-point lower carbon conversion for a given reactor outlet temperature. The gasifier outlet temperature must be raised by 90 K in order to achieve the same conversion as in a water slurry-fed reactor; the peak reactor temperature increases by 220 K as a result. Net oxygen savings of 8% are estimated for a system with a CO[subscript 2] slurry-fed gasifier relative to one with water slurry and the same level of conversion. BP (Firm) 2016-10-03T19:57:21Z 2016-10-03T19:57:21Z 2012-12 2012-11 Article http://purl.org/eprint/type/JournalArticle 03062619 http://hdl.handle.net/1721.1/104643 Botero, Cristina, Randall P. Field, Howard J. Herzog, and Ahmed F. Ghoniem. “Impact of Finite-Rate Kinetics on Carbon Conversion in a High-Pressure, Single-Stage Entrained Flow Gasifier with coal–CO2 Slurry Feed.” Applied Energy 104 (April 2013): 408–417. https://orcid.org/0000-0001-9078-8484 https://orcid.org/0000-0001-8730-272X en_US http://dx.doi.org/10.1016/j.apenergy.2012.11.028 Applied Energy Creative Commons Attribution-NonCommercial-NoDerivs License http://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf Elsevier MIT web domain |
| spellingShingle | Botero, Cristina Field, Randall Ghoniem, Ahmed F Herzog, Howard J. Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed |
| title | Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed |
| title_full | Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed |
| title_fullStr | Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed |
| title_full_unstemmed | Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed |
| title_short | Impact of finite-rate kinetics on carbon conversion in a high-pressure, single-stage entrained flow gasifier with coal–CO2 slurry feed |
| title_sort | impact of finite rate kinetics on carbon conversion in a high pressure single stage entrained flow gasifier with coal co2 slurry feed |
| url | http://hdl.handle.net/1721.1/104643 https://orcid.org/0000-0001-9078-8484 https://orcid.org/0000-0001-8730-272X |
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