Graphical Abstract Figure
Graphical Abstract Figure
Close modal

Abstract

In this work, a combined supercritical CO2 recompression Brayton cycle (SCRBC)/organic flash cycle with a two-phase expander (OFCT) system is proposed to improve the thermal efficiency of the SCRBC, which utilizes a two-phase expander to replace the high-pressure throttling valve of a basic organic flash cycle (OFC). In addition, the OFCT is coupled at the waste heat end of the SCRBC as the bottom cycle for the use of waste heat at low temperatures. A comprehensive comparison is carried out for different organic working fluids, including the R123, R245fa, R142B, R236ea, and R600, regarding the thermal performance, environmental effect, and safety levels. Furthermore, influences of various factors on the thermal performance of the combined SCRBC/OFCT cycle are also examined, including the top cycle pressure ratio, top cycle turbine inlet temperature, mass flowrate ratio, evaporation temperature, and the condenser's pinch point temperature difference. A multi-objective optimization approach is employed on the combined SCRBC/OFCT system, which considers both the thermal efficiency and the specific investment cost as the objective function, and the optimization procedure is implemented through the nondominated sorting genetic algorithm II (NSGA-II) algorithm. The Pareto solution set and the compromise solution are finally obtained. The results indicate that the optimized combined SCRBC/OFCT system can improve the thermal efficiency by 11.75% and 9.70% when compared with the SCRBC and SCRBC/OFC, respectively.

References

1.
Kim
,
S.
,
Cho
,
Y.
,
Kim
,
M. S.
, and
Kim
,
M.
,
2018
, “
Characteristics and Optimization of Supercritical CO2 Recompression Power Cycle and the Influence of Pinch Point Temperature Difference of Recuperators
,”
Energy
,
147
, pp.
1216
1226
.
2.
Cheng
,
W. L.
,
Huang
,
W. X.
, and
Nian
,
Y. L.
,
2017
, “
Global Parameter Optimization and Criterion Formula of Supercritical Carbon Dioxide Brayton Cycle With Recompression
,”
Energy Convers. Manage.
,
150
, pp.
669
677
.
3.
Sharma
,
O. P.
,
Kaushik
,
S. C.
, and
Manjunath
,
K.
,
2017
, “
Thermodynamic Analysis and Optimization of a Supercritical CO2 Regenerative Recompression Brayton Cycle Coupled With a Marine gas Turbine for Shipboard Waste Heat Recovery
,”
Therm. Sci. Eng. Prog.
,
3
, pp.
62
74
.
4.
Park
,
S. H.
,
Kim
,
J. Y.
,
Yoon
,
M. K.
,
Rhim
,
D. R.
, and
Yeom
,
C. S.
,
2018
, “
Thermodynamic and Economic Investigation of Coal-Fired Power Plant Combined With Various Supercritical CO2 Brayton Power Cycle
,”
Appl. Therm. Eng.
,
130
, pp.
611
623
.
5.
Reznicek
,
E. P.
,
Hinze
,
J. F.
,
Nellis
,
G. F.
,
Anderson
,
M. H.
, and
Braun
,
R. J.
,
2021
, “
Simulation of the Supercritical CO2 Recompression Brayton Power Cycle With a High-Temperature Regenerator
,”
Energy Convers. Manage.
,
229
, p.
113678
.
6.
Mohammed
,
R. H.
,
Alsagri
,
A. S.
, and
Wang
,
X.
,
2020
, “
Performance Improvement of Supercritical Carbon Dioxide Power Cycles Through Its Integration With Bottoming Heat Recovery Cycles and Advanced Heat Exchanger Design: A Review
,”
Int. J. Energy Res.
,
44
(
9
), pp.
7108
7135
.
7.
Cao
,
Y.
,
Wang
,
Z.
,
Ma
,
N.
, and
Li
,
L.
,
2020
, “
Thermodynamic Properties of Supercritical CO2 Brayton/Organic Rankine Cycle Combined System
,”
J. Eng. Therm. Energy Power
,
35
(
4
), pp.
9
15
.
8.
Besarati
,
S. M.
, and
Goswami
,
D. Y.
,
2014
, “
Analysis of Advanced Supercritical Carbon Dioxide Power Cycles With a Bottoming Cycle for Concentrating Solar Power Applications
,”
ASME J. Sol. Energy Eng.
,
136
(
1
), p.
010904
.
9.
Kim
,
K. H.
, and
Perez-Blanco
,
H.
,
2015
, “
Performance Analysis of a Combined Organic Rankine Cycle and Vapor Compression Cycle for Power and Refrigeration Cogeneration
,”
Appl. Therm. Eng.
,
91
, pp.
964
974
.
10.
Yan
,
Z.
,
Zhang
,
Y.
, and
Sun
,
W.
,
2021
, “
Industrial Waste Heat Organic Flash Cycle Recovery Scheme and Exergy Performance Analysis
,”
Energy Metall. Ind.
,
40
(
5
), pp.
48
52
.
11.
Ho
,
T.
,
Mao
,
S. S.
, and
Greif
,
R.
,
2012
, “
Comparison of the Organic Flash Cycle (OFC) to Other Advanced Vapor Cycles for Intermediate and High Temperature Waste Heat Reclamation and Solar Thermal Energy
,”
Energy
,
42
(
1
), pp.
213
223
.
12.
Que
,
Y.
,
Hu
,
Z.
,
Ren
,
S.
, and
Jiang
,
Z.
,
2022
, “
Thermodynamic Analysis of a Combined Recompression Supercritical Carbon Dioxide Brayton Cycle With an Organic Flash Cycle for Hybrid Solar-Geothermal Energies Power Generation
,”
Front. Energy Res.
,
10
, p.
924134
.
13.
Han
,
C. H.
, and
Kim
,
K. H.
,
2014
, “
Exergetical Analysis of Organic Flash Cycle With Two-Phase Expander for Recovery of Finite Thermal Reservoirs
,”
J. Therm. Sci.
,
23
(
6
), pp.
572
579
.
14.
Mahmoudi
,
S. M. S.
,
Sardroud
,
R. G.
,
Sadeghi
,
M.
, and
Rosen
,
M. A.
,
2022
, “
Integration of Supercritical CO2 Recompression Brayton Cycle With Organic Rankine/Flash and Kalina Cycles: Thermoeconomic Comparison
,”
Sustainability
,
14
(
14
), p.
8769
.
15.
Mondal
,
S.
, and
De
,
S.
,
2019
, “
Waste Heat Recovery Through Organic Flash Cycle (OFC) Using R245fa–R600 Mixture as the Working Fluid
,”
Clean Technol. Environ. Policy
,
21
(
8
), pp.
1575
1586
.
16.
Mondal
,
S.
, and
De
,
S.
,
2017
, “
Power by Waste Heat Recovery From Low Temperature Industrial Flue Gas by Organic Flash Cycle (OFC) and Transcritical-CO2 Power Cycle: A Comparative Study Through Combined Thermodynamic and Economic Analysis
,”
Energy
,
121
, pp.
832
840
.
17.
Meng
,
D.
,
Liu
,
Q.
, and
Ji
,
Z.
,
2020
, “
Performance Analyses of Regenerative Organic Flash Cycles for Geothermal Power Generation
,”
Energy Convers. Manage.
,
224
, p.
113396
.
18.
Zhang
,
F.
,
Liao
,
G.
,
E
,
J.
,
Chen
,
J.
, and
Leng
,
E.
,
2021
, “
Comparative Study on the Thermodynamic and Economic Performance of Novel Absorption Power Cycles Driven by the Waste Heat From a Supercritical CO2 Cycle
,”
Energy Convers. Manage.
,
228
, p.
113671
.
19.
Wu
,
C.
,
Wang
,
S.
, and
Li
,
J.
,
2018
, “
Exergoeconomic Analysis and Optimization of a Combined Supercritical Carbon Dioxide Recompression Brayton/Organic Flash Cycle for Nuclear Power Plants
,”
Energy Convers. Manage.
,
171
, pp.
936
952
.
20.
Marchionni
,
M.
,
Bianchi
,
G.
, and
Tassou
,
S. A.
,
2018
, “
Techno-Economic Assessment of Joule-Brayton Cycle Architectures for Heat to Power Conversion From High-Grade Heat Sources Using CO2 in the Supercritical State
,”
Energy
,
148
, pp.
1140
1152
.
21.
Wang
,
X.
,
2022
, “
Design and Economic Analysis of Supercritical Carbon Dioxide Coal-Fired Power Generation System
,”
North China Electric Power University
,
Beijing
.
22.
Lee
,
H. Y.
,
Park
,
S. H.
, and
Kim
,
K. H.
,
2016
, “
Comparative Analysis of Thermodynamic Performance and Optimization of Organic Flash Cycle (OFC) and Organic Rankine Cycle (ORC)
,”
Appl. Therm. Eng.
,
100
, pp.
680
690
.
23.
Wu
,
C.
,
Wang
,
S. S.
,
Jiang
,
X.
, and
Li
,
J.
,
2017
, “
Thermodynamic Analysis and Performance Optimization of Transcritical Power Cycles Using CO2-Based Binary Zeotropic Mixtures as Working Fluids for Geothermal Power Plants
,”
Appl. Therm. Eng.
,
115
, pp.
292
304
.
24.
Rao
,
Z.
,
Xue
,
T.
,
Huang
,
K.
, and
Liao
,
S.
,
2019
, “
Multi-Objective Optimization of Supercritical Carbon Dioxide Recompression Brayton Cycle Considering Printed Circuit Recuperator Design
,”
Energy Convers. Manage.
,
201
, p.
112094
.
You do not currently have access to this content.