Thermodynamic analysis of reheat cycle steam power plants (original) (raw)
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Effect of key parameters on thermodynamic and thermoeconomic performance of steam power plant
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Journal of Engineering Research, 2021
Exergoeconomic (thermoeconomic) analysis is performed on Alkhoms steam power plant. The nominal power of the plant is 120 MW. The analysis is based on real-time data and performed for three different loads. The main factor of load variation is the variation of the steam mass flow rate. These loads are 120 MW (full load), 60 MW (part load), and 100 MW (real-time operation). It is worth to mention that high-pressure heaters are out of service these days. A systematic and general methodology for defining and calculating exergetic efficiencies, exergy destruction, and exergy related to costs in thermal systems is presented. The methodology is based on the Specific Exergy Costing (SPECO) method. Results of the exergy analysis showed the exergetic efficiency (effectiveness) increases from 34.74% at the real-time operation to 40.96% at full operating load, and hence the ratio of the total exergy destruction to fuel input exergy decreases from 64.46% at a real-time operation to 59.6 at part load up to 57.88% at full operating load. The exergoeconomic analysis results the average specific cost is 0.177 /kWhatreal−timeoperationand0.113/kWh at real-time operation and 0.113 /kWhatreal−timeoperationand0.113/kWh at part load, and 0.102 /kWhatfulloperatingloadtakingintoconsiderationtheescalationoffuelprice(levelizedfuelcost).Itisfoundthatthecostofexergydestructioninthesteamgeneratorpresentsthemaincontributiontothetotalcostofexergyloss;itsvaluevariesinthesteamgeneratorfrom8296/kWh at full operating load taking into consideration the escalation of fuel price (levelized fuel cost). It is found that the cost of exergy destruction in the steam generator presents the main contribution to the total cost of exergy loss; its value varies in the steam generator from 8296 /kWhatfulloperatingloadtakingintoconsiderationtheescalationoffuelprice(levelizedfuelcost).Itisfoundthatthecostofexergydestructioninthesteamgeneratorpresentsthemaincontributiontothetotalcostofexergyloss;itsvaluevariesinthesteamgeneratorfrom8296/h at the real-time operation to 6560 /hatfulloperatingload,whileexergydestructioncostatpartloadisatanotablevalueof3495/h at full operating load, while exergy destruction cost at part load is at a notable value of 3495 /hatfulloperatingload,whileexergydestructioncostatpartloadisatanotablevalueof3495/h due to low fuel consumption. The contributions and the variation of exergy destruction cost with load are lower for the other components.
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Energy Sources, Part A: Recovery, Utilization, And Environmental Effects, 2010
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Thermal steam power plants represent the most important and dependable type for supplying the base load of electricity around the world. The thermos-economic analysis is an important tool for improving the performance of thermal steam power plants. In the present study, a thermo-economic analysis of a simple steam power plant for different boiler pressure was performed. The analysis comprises the energy, exergy, entropy, economics, and exergy-economic of a simple cycle steam power plant for different boiler pressure. The analysis was performed for a simple steam power plant with the constant output power of 10 MW and the boiler pressure is varied from 10 bar to 100 bar by a step of 10 bar. For each boiler pressure and constant output power, firstly, the fuel mass flow rate, steam flow rate, energy and exergy efficiency, and cost of electricity were calculated. Secondly, entropy generation, exergy destruction, and exergy efficiency for each component were calculated. Finally, exergy ...
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Exergy analysis is an important tool to identify the improvements in various industrial processes. In this study, the existing steam power plant is examined based on energy and exergy analyses. The steam network in the power plant is comprised of two sections, one of them is used for paddy drying, while other portion is used to operate the turbine for in-house electricity production. Mass, energy, and exergy balances are applied to individual equipment of the plant. The power plant is modeled and simulated using Aspen HYSYS® V10. The calculated thermodynamic values are used for in-depth analysis of the power plant. Case-studies are included in this study to show the effect of various operational parameters on the process efficiency. The analysis shows that the boiler is the major source of exergy destruction, because of the incomplete combustion process, and inappropriate insulations. The remedial actions are also suggested in the study.
IJERT-Second Law Based Thermodynamic Analysis of Cogeneration Plant
International Journal of Engineering Research and Technology (IJERT), 2014
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Thermal Analysis of Steam Turbine Power Plants
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