Thermodynamic and economic analysis of dual-pressure internal and external compression air separation units under variable operating conditions

LI Jiarui; LI Ruifan; XU Hongyu; XU Cheng

doi:10.11949/0438-1157.20260506

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Thermodynamic and economic analysis of dual-pressure internal and external compression air separation units under variable operating conditions

更新时间：2026-06-18

- Thermodynamic and economic analysis of dual-pressure internal and external compression air separation units under variable operating conditions
- CIESC Journal (2026)
- 作者机构：
  
  新能源电力系统全国重点实验室，华北电力大学，北京 102206
- 作者简介：
- 基金信息：
- DOI：10.11949/0438-1157.20260506
  CLC： TQ 116.11
- Received：13 April 2026，
  
  Revised：2026-06-17，
  
  Accepted：18 June 2026，
- 稿件说明：
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LI Jiarui, LI Ruifan, XU Hongyu, et al. Thermodynamic and economic analysis of dual-pressure internal and external compression air separation units under variable operating conditions[J/OL]. CIESC Journal, 2026.
DOI：

LI Jiarui, LI Ruifan, XU Hongyu, et al. Thermodynamic and economic analysis of dual-pressure internal and external compression air separation units under variable operating conditions[J/OL]. CIESC Journal, 2026. DOI： 10.11949/0438-1157.20260506.

摘要

为支撑可再生能源电力并网需求，煤基半闭式CO

循环发电系统需长时间偏离设计工况运行，作为系统主要能耗来源，空分的变工况性能对发电系统宽负荷高效运行至关重要。构建了可同时生产6.6 MPa与33.4 MPa氧气的空分系统变工况模型，提出滑压运行的变工况策略，探究了内、外压缩空分在不同工况下的热力学性能及技术经济性。结果表明，在100%~80%负荷运行范围内，相较于内压缩空分，外压缩空分的单位制氧能耗降低了6.70%~8.52%，初期投资成本高3.02%，产品平准化成本低5.54%。外压缩空分在运行成本和变工况效能方面更具优势，内压缩空分则在高压安全性与初期投资方面占优，在工程应用中应根据具体需求综合权衡后合理选型。

Abstract

In order to meet the grid integration requirement for renewable energy

coal-fueled semi-closed CO

cycle power generation system is required to operate under off-design conditions for extended periods. As the primary energy consumption component within the system

the off-design performance of air separation unit (ASU) is critical for the efficient operation of the power generation system over a wide load range. This paper proposes the off-design model for the ASU capable of simultaneously producing oxygen at two pressure levels: 6.6 MPa and 33.4 MPa. Based on sliding pressure control strategies

this study investigates the thermodynamic performance and techno-economic viability of two ASU configurations

internal compression (IC) and external compression (EC)

under variable operating conditions. The results indicate that within the load range of 100% to 80%

the EC model achieves a reduction in the specific energy consumption of 6.70% to 8.52%

has a 3.02% higher initial investment c

ost

and lowers the levelized cost of product by 5.54% compared to the IC model. The EC model has advantages in operating cost and off-design performance

while the IC model has better performance in terms of high-pressure safety and initial investment. Therefore

the appropriate model should be selected with careful consideration based on specific requirements in engineering applications.

关键词

Keywords

references

杨勇平 , 陈衡 , 郝俊红 , 等 . “双碳”目标下我国燃煤发电转型升级发展路径 [J ] . 中国电机工程学报 , 2024 , 44 ( 17 ): 6900 - 6909 .

Yang Y P , Chen H , Hao J H , et al . Development pathways for the transformation and upgrading of China’s coal-fired power generation under the goals of carbon peak and carbon neutrality [J ] . Proceedings of the CSEE , 2024 , 44 ( 17 ): 6900 - 6910

Koohestanian E , Shahraki F . Review on principles, recent progress, and future challenges for oxy-fuel combustion CO 2 capture using compression and purification unit [J ] . Journal of Environmental Chemical Engineering , 2021 , 9 ( 4 ): 105777 .

Moon J H , Jo S H , Park S J , et al . Carbon dioxide purity and combustion characteristics of oxy firing compared to air firing in a pilot-scale circulating fluidized bed [J ] . Energy , 2019 , 166 : 183 - 192 .

Hu Y Q , Kobayashi N , Hasatani M . The reduction of recycled-NO x in coal combustion with O2/recycled flue gas under low recycling ratio [J ] . Fuel , 2001 , 80 ( 13 ): 1851 - 1855 .

Zhang N , Lior N . Two novel oxy-fuel power cycles integrated with natural gas reforming and CO 2 capture [J ] . Energy , 2008 , 33 ( 2 ): 340 - 351 .

许宏宇 . 富氧燃烧半闭式超临界CO 2 循环构建方法与变工况特性研究 [D ] . 北京 : 华北电力大学 , 2025 .

Xu H Y . Design methodology and off-design characteristics investigation of the oxygen-fuel combu stion semi-closed supercritical CO 2 cycle [D ] . Beijing : North China Electric Power University , 2025

杨威 , 辛团团 , 蒯艺文 , 等 . 煤与CO 2 协同转化的半闭式动力循环系统构建与热力学分析 [J ] . 中国电机工程学报 , 2026 , 46 ( 10 ): 4164 - 4174 .

Yang W , Xin T T , Kuai Y W , et al . System proposal and thermodynamic analysis of the semi-closed power cycle based on coal and CO 2 synergistic conversion [J ] . Proceedings of the CSEE , 2026 , 46 ( 10 ): 4164 - 4174 .

阎维平 , 赵文娟 , 孙俊威 , 等 . 富氧燃烧发电机组制氧设备供电方式的优化分析 [J ] . 动力工程学报 , 2012 , 32 ( 1 ): 66 - 71 .

Yan W P , Zhao W J , Sun J W , et al . Optimization of power supply mode for ASU of oxygen-enriched combustion power generating sets [J ] . Journal of Chinese Society of Power Engineering , 2012 , 32 ( 1 ): 66 - 71 .

Hagi H , Le Moullec Y , Nemer M , et al . Performance assessment of first generation oxy-coal power plants through an exergy-based process integration methodology [J ] . Energy , 2014 , 69 : 272 - 284 .

Zhao Y J , Duan Y Y , Liu Q , et al . Life cycle energy-economy-environmental evaluation of coal-based CLC power plant vs. IGCC, USC and oxy-combustion power plants with/without CO 2 capture [J ] . Journal of Environmental Chemical Engineering , 2021 , 9 ( 5 ): 106121 .

Fu C , Gundersen T . Using exergy analysis to reduce power consumption in air separation units for oxy-combustion processes [J ] . Energy , 2012 , 44 ( 1 ): 60 - 68 .

Fu C , Gundersen T . Recuperative vapor recompression heat pumps in cryogenic air separation processes [J ] . Energy , 2013 , 59 : 708 - 718 .

Arnaiz del Pozo C , Jiménez Álvaro Á , Roncal Casano J J , et al . Exergoeconomic assessment of air separation units for pressurized O 2 production incorporating two-phase expanders [J ] . Cryogenics , 2022 , 124 : 103477 .

Ebrahimi A , Meratizaman M , Akbarpour Reyhani H , et al . Energetic, exergetic and economic assessment of oxygen production from two columns cryogenic air separation unit [J ] . Energy , 2015 , 90 : 1298 - 1316 .

常亮 , 刘兴高 . 内部热耦合空分塔的节能优化分析 [J ] . 化工学报 , 2012 , 63 ( 9 ): 2936 - 2940 .

Chang L , Liu X G . Energy optimization analysis of internal thermally coupled air separation columns [J ] . CIESC Journal , 2012 , 63 ( 9 ): 2936 - 2940 .

文兆伦 , 李沛睿 , 张忠林 , 等 . 基于自热再生的隔壁塔深冷空分工艺设计及优化 [J ] . 化工学报 , 2023 , 74 ( 7 ): 2988 - 2998 .

Wen Z L , Li P R , Zhang Z L , et al . Design and optimization of cryogenic air separation process with dividing wall column based on self-heat regeneration [J ] . CIESC Journal , 2023 , 74 ( 7 ): 2988 - 2998 .

van der Ham L V , Kjelstrup S . Exergy analysis of two cryogenic air separation processes [J ] . Energy , 2010 , 35 ( 12 ): 4731 - 4739 .

丁传琪 . 5000Nm 3 /h空分的两种内压缩流程比较 [J ] . 低温与特气 , 2013 , 31 ( 2 ): 18 - 21 .

Ding C Q . Comparison of Two Kinds of Inner Compression Process For 5000 Nm 3 /h Air Separation Plant [J ] . Low Temperature and Specialty Gases , 2013 , 31 ( 2 ): 18 - 21 .

Hamayun M H , Ramzan N , Hussain M , et al . Evaluation of two-column air separation processes based on exergy analysis [J ] . Energies , 2020 , 13 ( 23 ): 6361 .

Singla R , Chowdhury K . Comparisons of thermodynamic and economic performances of cryogenic air separation plants designed for external and internal compression of oxygen [J ] . Applied Thermal Engineering , 2019 , 160 : 114025 .

Xin T T , Li S X , Yang W , et al . Thermodynamic comparison of cryogenic air separation units with external and internal compression of oxygen designed for the coal-fueled allam cycle [J ] . Energy , 2025 , 333 : 137325 .

Zaryab S A , Scaccabarozzi R , Martelli E . Advanced part-load control strategies for the allam cycle [J ] . Applied Thermal Engineering , 2020 , 168 : 114822 .

Xin T T , Yang W , Li S X , et al . Development of a novel coal-fueled nearly zero emission semi-closed supercritical CO2 cycle with the net efficiency above 50 % based on the process splitting method [J ] . Energy , 2025 , 318 : 134944 .

Huang J J , Xu Y J , Guo H , et al . Dynamic performance and control scheme of variable-speed compressed air energy storage [J ] . Applied Energy , 2022 , 325 : 119338 .

Ma Y G , Morosuk T , Liu M , et al . Development and comparison of control schemes for the off-design operation of a recompression supercritical CO 2 cycle with an intercooled main compressor [J ] . Energy , 2020 , 211 : 119011 .

Du Y C , Luo Y Q , Yang P L , et al . Rigorous design and economic optimization of reactive distillation column considering real liquid hold-up and hydraulic conditions of industrial device [J ] . Chinese Journal of Chemical Engineering , 2024 , 76 : 211 - 226 .

Madsen E , Neerup R , Gladis A , et al . Pressure drop of structured packing in pilot column and comparison to common correlations [J ] . Chinese Journal of Chemical Engineering , 2023 , 64 : 281 - 291 .

秦晓巧 , 谭宏博 , 温娜 . 储能式低温空分系统热力学与经济性分析 [J ] . 化工学报 , 2024 , 75 ( 7 ): 2409 - 2421 .

Qin X Q , Tan H B , Wen N . Thermodynamic and economic analysis of air separation unit with energy storage and generation [J ] . CIESC Journal , 2024 , 75 ( 7 ): 2409 - 2421 .

Bai T , Shi W Y , Xue X J , et al . Thermodynamic and economic analysis of the compressed air energy storage coupled with the combustible solid waste power plant [J ] . Journal of Energy Storage , 2026 , 141 : 119345 .

Morandin M , Mercangöz M , Hemrle J , et al . Thermoeconomic design optimization of a thermo-electric energy storage system based on transcritical CO 2 cycles [J ] . Energy , 2013 , 58 : 571 - 587 .

Singla R , Chowdhury K . Determining design criteria to reduce power and cost in filling high-pressure oxygen cylinders directly from cryogenic air separation plants [J ] . Cryogenics , 2021 , 116 : 103299 .

Huo C J , Sun J J , Song P . Energy, exergy and economic analyses of an optimal use of cryogenic liquid turbine expander in air separation units [J ] . Chemical Engineering Research and Design , 2023 , 189 : 194 - 209 .

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