Thermodynamic Modelling, Technical and Operational Issues of Supercritical Carbon Dioxide Power Generation Cycles for Industrial Applications: A Literature Review (original) (raw)

Supercritical CO2 cycles in combined-cycle power systems

2022

The use of supercritical carbon dioxide (sCO2) cycles in waste heat to power (WHP) applications, specifically in combined-cycle power systems, can help industrial and power generation facilities save money and increase efficiency. According to the literature, the main hindrance facing the commercialization of these systems is their relative novelty compared to other well-established power systems like the steam and organic Rankine cycles. This thesis aims to reveal and present detailed economic and thermodynamic features and characteristics of these sCO2 power cycles to help increase the market stakeholders' confidence in such a new technology. Hence, accelerate its promotion and application in established facilities and new projects. Therefore, five main components were implemented and reported in this work: (1) Review and statistical analysis of a large pool of recently published academic articles and technical reports that have focused on the economic and technical performanc...

Optimization and Comparison of Direct and Indirect Supercritical Carbon Dioxide Power Plant Cycles for Nuclear Applications

Volume 4: Energy Systems Analysis, Thermodynamics and Sustainability; Combustion Science and Engineering; Nanoengineering for Energy, Parts A and B, 2011

Results of analyses performed using the UniSim process analyses software to evaluate the performance of both a direct and indirect supercritical CO2 Brayton power plant cycle with recompression at different reactor outlet temperatures are presented. The direct supercritical CO2 power plant cycle transferred heat directly from a 600 MWt reactor to the supercritical CO2 working fluid supplied to the turbine generator at approximately 20 MPa. The indirect supercritical CO2 cycle assumed a helium-cooled Very High Temperature Reactor (VHTR), operating at a primary system pressure of approximately 7.0 MPa, delivered heat through an intermediate heat exchanger to the secondary indirect supercritical CO2 recompression Brayton cycle, again operating at a pressure of about 20 MPa. For both the direct and indirect power plant cycles, sensitivity calculations were performed for reactor outlet temperature between 550°C and 850°C. The UniSim models used realistic component parameters and operatin...

PARAMETRIC ANALYSIS OF CARBON DIOXIDE TRANSCRITICAL AND SUPERCRITICAL POWER CYCLES USING LOW GRADE HEAT SOURCE

This paper considers carbon dioxide transcritical and supercritical power cycles driven by low temperature flue gases exhaust from a gas turbine. Transcritical CO2 Rankine and supercritical CO2 Brayton cycles were studied at steady state conditions and their performance were compared. Furthermore, the study carried out parametric analysis to investigate the cycles' performance in terms of thermal efficiency and the network output at different turbine inlet temperatures. A mathematical model was developed to carry out the analysis based on the first law of thermodynamics. In order to simulate cycle performance and generate parametric tables a simulation model was developed using Engineering Equations Solver (EES). The efficiencies of the cycles were compared and it was found that transcritical Rankine cycle generates higher efficiency and net power output compared to supercritical Braytoncycle for the same turbine inlet conditions. Parametric analysis showed that as the turbine inlet temperature increases, the gas heater pressure that gives optimum efficiency increases.

Challenges in Supercritical CO2 power cycle technology and first operational experience at CVR

2018

CVR, Research Centre Rez, Czech Republic, is investigating advanced Brayton cycles using supercritical CO2 (sCO2) as working fluid, which has potential for high thermodynamic efficiency of a power plant. This innovative technology needs to be demonstrated and experimentally proven by numerous tests. For this purpose, CVR has built a sCO2 experimental loop within Sustainable Energy project (SUSEN). This unique facility is flexible, modifiable and suitable for performance testing of key components of sCO2 conversion cycles such as compressor, turbine, heat exchanger and valves together with material research with wide range of parameters: temperature up to 550°C, pressure up to 30 MPa and mass flow rate up to 0.35 kg/s. This paper covers literature survey on major challenges in sCO2 development and the design of the loop with description of key components. The first operational experience is given as well as the discussion on the measured data set. Finally, it is outlined how the sCO2...

Design considerations on a small scale supercritical CO2 power system for industrial high temperature waste heat to power recovery applications

2016

Existing industrial processes are energy intensive environments with a multitude of waste heat streams at different temperature levels whose recovery would undoubtedly contribute to the enhancement of the sustainability of the industrial sites and their products. In particular, the geographical distribution and size of the available waste heat potential is very widespread with most sources being small to medium size, up to 1 MW and fewer of larger size above 1 MW. Among the waste heat to power conversion approaches, the usage of bottoming thermodynamic cycles based on carbon dioxide in supercritical phase (sCO2) provides significant advantages compared to more conventional technologies such as the Organic Rankine Cycle (ORC) systems that are nowadays commercially available even at small scale (~10 kWe). However, unlike the large sCO2 systems that are already on the market (~ MWe), medium and small size ones are still under development. In the current work, the challenges involved in...

Performance analyses and optimization of a regenerative supercritical carbon dioxide power cycle with intercooler and reheater

Seatific Engineering Research Journal, 2021

Supercritical CO2 (sCO2) power cycles play an important role in energy production as they are more efficient and more compact than conventional energy production systems. Therefore, they are widely used in different systems such as nuclear systems, renewable energy systems, heat recovery systems, fossil power plants, submarines, and some commercial and navy ships that produce a wide range of power operating in different temperature ranges. It has become very popular especially in recent years due to its widespread use and technical capabilities. This study analyses the effects of some design parameters (pressure ratio and temperature ratio) on the performance criteria (net work, thermal efficiency, back work ratio, and total entropy generation) and draws some optimum working conditions by means of the purpose of using. Results show that to obtain an optimum system according to maximum thermal efficiency or maximum net work the design range for the compression ratio for temperature r...

Normalized performance optimization of supercritical, CO2-based power cycles

Energy, 2015

This study considers the multivariable thermodynamic analysis and optimization of transcritical Rankine cycles operating with carbon dioxide as working fluid. Three dependent variables were used as figures of merit: the net power produced by the cycle, and its 1st and 2nd Law efficiencies, all calculated in absolute terms and per unit of global conductance (UA) Total , where (UA) Total accounts for the conductance of all heat exchangers used in the cycle. The key variables were the high pressure of the CO 2 within the cycle and the temperature of the heat source, along with four different cycle configurations: (i) a basic power cycle, (ii) a cycle with a recuperator, (iii) a cycle with reheating and (iv) a cycle with a recuperator and reheating , namely, combined cycle. The optimization process relied on optimization routines and considered latent and sensible heat sources. This procedure was able to show that while the individually defined figures of merit mostly presented established trends, the normalized figures of merit (i.e., those defined per unit of UA) are highly dependent on the parameters considered and clearly show the existence of optimum values, which are a function of the cycle's configuration, figures of merit considered and operation parameters.

Optimization and comparison on supercritical CO2 power cycles integrated within coal-fired power plants considering the hot and cold end characteristics

Energy Conversion and Management, 2019

The integration of supercritical CO2 (SCO2) cycle instead of steam Rankine cycle may be a revolutionary technique to increase the efficiency of coal-fired power plants. To effectively extract exergy from the fluegas and convert exergy to power, the characteristics of hot end (heat reservoir) and cold end (heat sink) should be fully considered, and the system multi-parameters should be optimized. In this study, based on a benchmark coal-fired power plant integrated with a recompression SCO2 power cycle, quantitative efficiency enhancements of system improvements of the hot end and cold end for SCO2 power cycle are calculated and compared. The optimized efficiency of benchmark coal-fired plant integrated with recompression SCO2 power cycle is 45.43%. When the fluegas at the economizer outlet is effectively used, the power plant efficiency can be increased by 1.32%. With single and double reheats to decrease the heat transfer irreversibility of the hot end, the power plant efficiency can be increased by 1.77% and 2.24%, respectively. Cold end optimization with single intercooling and cold air preheating can increase the power plant efficiency by 0.32% and 0.33%, respectively. Finally, a simple structure system and a complex structure system are proposed. With optimal system parameters, the power plant efficiencies of the complex and simple systems are 49.32% and 48.52%, respectively.

Thermodynamic Analysis of a 500MWe Coal-fired Supercritical Power Plant with CO2 Capture Integrated with Kalina Cycle for Combined Cooling and Power

2020

Department of Mechanical Engineering, National Institute of Technology Durgapur, Durgapur-713 209, West Bengal, India Mejia Thermal Power Station, Damodar Valley Corporation, Mejia-722 183, Bankura, West Bengal, India E-mail: sujitkarmakar@yahoo.com <em>Manuscript received online 16 June 2020, revised and accepted 11 August 2020</em> A thermodynamic study is carried out on a 500MWe coal based supercritical thermal power plant (base plant) with MonoEthanolAmine (MEA) based CO<sub>2</sub> capture unit integrated with a Kalina Cycle (Low-grade energy cycle) setup for Combined Cooling and Power (CCP) generation using Indian High Ash (HA) coal as fuel, and the results are compared with an imported Low Ash (LA) coal. The modelling and simulation of the different plant configurations are done by using the simulation software "Cycle-Tempo". The base plant is integrated with the CO<sub>2</sub>capture unit working on MEA based post combustion carb...