Performance of a Semi-Closed Oxy-Fuel Combustion Combined Cycle (scoc-cc) with an Air Separation Unit (ASU)
(2018) ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition, GT 2018 3.- Abstract
The objective of this paper is to evaluate the performance of a semi-closed oxy-fuel combustion combined cycle (SCOC-CC) and its power penalties. The power penalties are associated with CO2 compression and high-pressure oxygen production in the air separation unit (ASU). The paper discusses three different methods for high pressure oxygen (O2) production. Method 1 is producing O2 directly at high pressure by compressing the air before the air separation takes place. Method 2 is producing O2 at low pressure and then compressing the separated O2 to the desired pressure with a compressor. Method 3 is alike the second method, except that the separated liquid O2 is pressurized... (More)
The objective of this paper is to evaluate the performance of a semi-closed oxy-fuel combustion combined cycle (SCOC-CC) and its power penalties. The power penalties are associated with CO2 compression and high-pressure oxygen production in the air separation unit (ASU). The paper discusses three different methods for high pressure oxygen (O2) production. Method 1 is producing O2 directly at high pressure by compressing the air before the air separation takes place. Method 2 is producing O2 at low pressure and then compressing the separated O2 to the desired pressure with a compressor. Method 3 is alike the second method, except that the separated liquid O2 is pressurized with a liquid oxygen pump to the desired pressure. The studied SCOC-CC is a dual-pressure level steam cycle due to its comparable efficiency with three pressure level steam cycle and less complexity. The SCOC-CC, ASU and CO2 compression train are modeled with the commercial heat and mass balance software IPSEpro. The paper analyzed the SCOC-CC performance at different combustion outlet temperatures and pressure ratios. The combustion outlet temperature (COT) varied from 1200 °C to 1550 °C and the pressure ratio varied from 25 to 45. The study is concerned with mid-sized SCOC-CC with a net power output 100 MW. The calculations were performed at the selected design point which was at 1400°C and pressure ratio at 37. The calculated power consumption of the O2 separation at a purity of 95 % was 719 kJ/kgO2. The power consumption for pressurizing the separated O2 (method 2) was 345 kJ/kgO2 whereas it was 4.4 kJ/kgO2 for pumping liquid O2 to the required pressure (method 3). The calculated power consumption for pressurizing and pumping the CO2-enriched stream was 323 kJ/kgCO2. The SCOC-CC gross efficiency was 57.6 %. The SCOCCC net efficiency at method 2 for air separation was 46.7 %. The gross efficiency was reduced by 9 % due to ASU and other 2 % due to CO2 compression. The SCOC-CC net efficiency at method 3 of the air separation was 49.6 %. The ASU reduced the gross efficiency by 6 % and additional 2 % by CO2 compression. Using method 3 for air separation gave a 3 % gain in cycle efficiency.
(Less)
- author
- Sammak, Majed LU ; Thern, Marcus LU and Genrup, Magnus LU
- organization
- publishing date
- 2018
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- keywords
- air separation unit, combined cycle, cycle performanc, liquid oxygen, oxy fuel, SCOC-CC
- host publication
- Coal, Biomass, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems
- volume
- 3
- article number
- GT2018-76218
- publisher
- American Society Of Mechanical Engineers (ASME)
- conference name
- ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition, GT 2018
- conference location
- Oslo, Norway
- conference dates
- 2018-06-11 - 2018-06-15
- external identifiers
-
- scopus:85053921846
- ISBN
- 9780791851043
- DOI
- 10.1115/GT2018-76218
- language
- English
- LU publication?
- yes
- id
- ea7f8128-3743-4d73-a42b-7a836d85dfe6
- date added to LUP
- 2018-10-22 10:35:09
- date last changed
- 2022-03-25 05:11:10
@inproceedings{ea7f8128-3743-4d73-a42b-7a836d85dfe6,
abstract = {{<p>The objective of this paper is to evaluate the performance of a semi-closed oxy-fuel combustion combined cycle (SCOC-CC) and its power penalties. The power penalties are associated with CO<sub>2</sub> compression and high-pressure oxygen production in the air separation unit (ASU). The paper discusses three different methods for high pressure oxygen (O<sub>2</sub>) production. Method 1 is producing O<sub>2</sub> directly at high pressure by compressing the air before the air separation takes place. Method 2 is producing O<sub>2</sub> at low pressure and then compressing the separated O<sub>2</sub> to the desired pressure with a compressor. Method 3 is alike the second method, except that the separated liquid O<sub>2</sub> is pressurized with a liquid oxygen pump to the desired pressure. The studied SCOC-CC is a dual-pressure level steam cycle due to its comparable efficiency with three pressure level steam cycle and less complexity. The SCOC-CC, ASU and CO<sub>2</sub> compression train are modeled with the commercial heat and mass balance software IPSEpro. The paper analyzed the SCOC-CC performance at different combustion outlet temperatures and pressure ratios. The combustion outlet temperature (COT) varied from 1200 °C to 1550 °C and the pressure ratio varied from 25 to 45. The study is concerned with mid-sized SCOC-CC with a net power output 100 MW. The calculations were performed at the selected design point which was at 1400°C and pressure ratio at 37. The calculated power consumption of the O<sub>2</sub> separation at a purity of 95 % was 719 kJ/kgO<sub>2</sub>. The power consumption for pressurizing the separated O<sub>2</sub> (method 2) was 345 kJ/kgO<sub>2</sub> whereas it was 4.4 kJ/kgO<sub>2</sub> for pumping liquid O<sub>2</sub> to the required pressure (method 3). The calculated power consumption for pressurizing and pumping the CO<sub>2</sub>-enriched stream was 323 kJ/kgCO<sub>2</sub>. The SCOC-CC gross efficiency was 57.6 %. The SCOCCC net efficiency at method 2 for air separation was 46.7 %. The gross efficiency was reduced by 9 % due to ASU and other 2 % due to CO<sub>2</sub> compression. The SCOC-CC net efficiency at method 3 of the air separation was 49.6 %. The ASU reduced the gross efficiency by 6 % and additional 2 % by CO<sub>2</sub> compression. Using method 3 for air separation gave a 3 % gain in cycle efficiency.</p>}},
author = {{Sammak, Majed and Thern, Marcus and Genrup, Magnus}},
booktitle = {{Coal, Biomass, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems}},
isbn = {{9780791851043}},
keywords = {{air separation unit; combined cycle; cycle performanc; liquid oxygen; oxy fuel; SCOC-CC}},
language = {{eng}},
publisher = {{American Society Of Mechanical Engineers (ASME)}},
title = {{Performance of a Semi-Closed Oxy-Fuel Combustion Combined Cycle (scoc-cc) with an Air Separation Unit (ASU)}},
url = {{http://dx.doi.org/10.1115/GT2018-76218}},
doi = {{10.1115/GT2018-76218}},
volume = {{3}},
year = {{2018}},
}