Performance Evaluation of an Organic Rankine Cycle Fed by Waste Heat Recovered from CO2 Capture Section
- Natural gas-fueled combined cycle (NGCC) allows to reach the best performance among power plants fed by fossil fuels, but causes considerable CO2 emissions. With the aim of reducing greenhouse gases impact, NGCC could be integrated with post-combustion CO2 removal systems, typically based on chemical solvents like amines, that cause very large net efficiency penalties (about 9-12 percentage points at 90% overall CO2 capture). To reduce these high capture penalties, exhaust gas recirculation (EGR) has been studied. To further enhance the overall plant efficiency, the recovery of available low temperature heat from the solvent-based CO2 removal systems could be also performed. Low temperature heat is available in flue gas coolers (80-100 degrees C), in the amine reboiler water cooling (130-140 degrees C) and in the splitter condenser (100-130 degrees C). This waste thermal energy could be recovered by means of an Organic Rankine Cycle (ORC) that is able to convert heat into electricity efficiently even at comparably low temperatures.Natural gas-fueled combined cycle (NGCC) allows to reach the best performance among power plants fed by fossil fuels, but causes considerable CO2 emissions. With the aim of reducing greenhouse gases impact, NGCC could be integrated with post-combustion CO2 removal systems, typically based on chemical solvents like amines, that cause very large net efficiency penalties (about 9-12 percentage points at 90% overall CO2 capture). To reduce these high capture penalties, exhaust gas recirculation (EGR) has been studied. To further enhance the overall plant efficiency, the recovery of available low temperature heat from the solvent-based CO2 removal systems could be also performed. Low temperature heat is available in flue gas coolers (80-100 degrees C), in the amine reboiler water cooling (130-140 degrees C) and in the splitter condenser (100-130 degrees C). This waste thermal energy could be recovered by means of an Organic Rankine Cycle (ORC) that is able to convert heat into electricity efficiently even at comparably low temperatures. N-Butane was found to be as the most promising organic working fluid for the cycle operating temperatures and pressures. ORC produces additional electrical power improving the global performance of the power plant, for example, up to 1-1.5 percentage points in efficiency.…
Author: | Vittorio Tola, Matthias FinkenrathORCiDGND |
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URL / DOI: | https://dergipark.org.tr/tr/pub/ijot/issue/5798/77141 |
DOI: | https://doi.org/10.5541/ijot.5000106929 |
Identifier: | 2146-1511 OPAC HS OPAC extern |
Identifier: | 1301-9724 OPAC HS OPAC extern |
Parent Title (German): | International Journal of Thermodynamics |
Publisher: | ITU Fac. of Mechanical Engineering |
Place of publication: | Gümüşsuyu-İstanbul |
Document Type: | Article |
Language: | English |
Year of first Publication: | 2015 |
Tag: | CO2 capture; NGCC; ORC; low temperature heat recovery |
Volume: | 18 |
Issue: | 4 |
Number of pages: | 9 Seiten |
First Page: | 225 |
Last Page: | 233 |
Institutes: | Fakultät Maschinenbau |
Dewey Decimal Classification: | 6 Technik, Medizin, angewandte Wissenschaften / 66 Chemische Verfahrenstechnik |
Open Access: | open_access |
Research focus: | FSP1: Energie |
Publication Lists: | Finkenrath, Matthias |
Publication reviewed: | begutachtet |
Release Date: | 2019/11/25 |