scholarly journals Modelling, Sensitivity and Exergy Analysis of Triple-Pressure Heat Recovery Steam Generator

2020 ◽  
Vol 8 (2) ◽  
pp. 106-114
Author(s):  
Suha Orçun MERT ◽  
Zehra ÖZÇELİK ◽  
Ceyda KÖK
Keyword(s):  
Steam Generator ◽  
Heat Recovery ◽  
Exergy Analysis ◽  
Heat Recovery Steam Generator

Exergy Analysis of Heat Recovery Steam Generator: Effects of Supplementary Firing and Desuperheater

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Hanieh Khalili Param ◽  
Ofelia A. Jianu
Keyword(s):  
Steam Generator ◽  
Heat Recovery ◽  
Exergy Analysis ◽  
Exergy Efficiency ◽  
Exergy Loss ◽  
Water Spray ◽  
Exergy Destruction ◽  
Heat Recovery Steam Generator ◽  
Set Point ◽  
A Value

Abstract Comprehensive exergy analysis of a heat recovery steam generator (HRSG) with two levels of delivered pressure is presented. The effects of supplementary firing as well as desuperheater set-point are considered to evaluate the exergy destruction of HRSG components. Burner firing rate is limited to a value that corresponds to the maximum allowable temperature of tube metal of high-pressure (HP) superheater. According to the exergy analysis performed in the current study, the exergy efficiency of HRSG is about 80% which means 20% of flue gas exergy (entering HRSG) is dissipated by HRSG destruction (∼14%) and stack exergy loss (∼6%). The stack exergy loss drops continuously as supplementary firing raises. It has also been determined that increasing the rate of supplementary firing boosts the exergy efficiency in the absence of water spray and reduces it when desuperheater is working. In addition, the exergy delivered to steam turbine shows a linear growth with burner heat while it is hardly affected by the set-point of desuperheater. Also, it is found that exergy loss through the stack is not sensitive to desuperheater set-point while it is on the decrease as burner duty raises. HP steam flow will raise with increasing the firing and/or decreasing the desuperheater set-point. HP evaporator has the most contribution in exergy destruction among HRSG components (∼40%), whereas HP superheater and desuperheater are components with a maximum sensitivity of exergy destruction to the amount of water spray.

scholarly journals Study of the effect of using duct burner on the functional parameters of the two repowered cycles through exergy analysis

2017 ◽  
Vol 21 (6 Part B) ◽  
pp. 3011-3023 ◽  
Author(s):  
Mehrabani Maghsoudi ◽  
Abdollah Mehrpanahi ◽  
Vahid Rouhani ◽  
Naser Nikbakht
Keyword(s):  
Power Generation ◽  
Steam Generator ◽  
Heat Recovery ◽  
Power Plants ◽  
Exergy Analysis ◽  
Combined Cycle ◽  
Heat Recovery Steam Generator ◽  
Steam Power ◽  
Steam Power Plants ◽  
Duct Burner

Steam power plants have been extensively used in Iran for a long time, yet no specific step has been taken for promoting their performance. In this regard, full repowering is considered as a way to enhance the performance of steam power plants. Furthermore, because of the continental condition of Iran, duct burners can be used as a common strategy to compensate for power generation shortage caused by environmental conditions. In this study, the effect of using a duct burner on the full repowering of Be?sat Steam Cycle representing both single-and dual-pressure cycles was investigated based on exergy analysis. The results showed that by using the duct burner, due to the increase in the heat recovery steam generator inlet gas temperature, the general thermal efficiency of the combined cycle and the exergy efficiency of the combined cycle and heat recovery steam generator decreased. However, the results revealed an increase in the stack temperature and resulting exergy losses, steam flow and power generation.

Investigation Tests of the P-134 Heat-Recovery Steam Generator Used as Part of the PGU-230T Combined-Cycle Power Unit

2019 ◽  
Vol 66 (5) ◽  
pp. 331-339
Author(s):  
M. N. Maidanik ◽  
A. N. Tugov ◽  
N. I. Mishustin ◽  
A. E. Zelinskii
Keyword(s):  
Power Unit ◽  
Steam Generator ◽  
Heat Recovery ◽  
Combined Cycle ◽  
Heat Recovery Steam Generator

Simulation and Optimization of Combined Cycle Power Cycles Through HRSG’s Heat Exchangers Arrangement and Parameters for Exergy and Cost

2012 ◽  
Author(s):  
Ravin G. Naik ◽  
Chirayu M. Shah ◽  
Arvind S. Mohite
Keyword(s):  
Power Plant ◽  
Steam Generator ◽  
Heat Exchangers ◽  
Heat Recovery ◽  
Second Law Of Thermodynamics ◽  
Combined Cycle ◽  
Heat Recovery Steam Generator ◽  
Exergetic Efficiency ◽  
Power Cycles ◽  
Combined Cycle Power Plant

To produce the power with higher overall efficiency and reasonable cost is ultimate aim for the power industries in the power deficient scenario. Though combined cycle power plant is most efficient way to produce the power in today’s world, rapidly increasing fuel prices motivates to define a strategy for cost-effective optimization of this system. The heat recovery steam generator is one of the equipment which is custom made for combined cycle power plant. So, here the particular interest is to optimize the combined power cycle performance through optimum design of heat recovery steam generator. The case of combined cycle power plant re-powered from the existing Rankine cycle based power plant is considered to be simulated and optimized. Various possible configuration and arrangements for heat recovery steam generator has been examined to produce the steam for steam turbine. Arrangement of heat exchangers of heat recovery steam generator is optimized for bottoming cycle’s power through what-if analysis. Steady state model has been developed using heat and mass balance equations for various subsystems to simulate the performance of combined power cycles. To evaluate the performance of combined power cycles and its subsystems in the view of second law of thermodynamics, exergy analysis has been performed and exergetic efficiency has been determined. Exergy concepts provide the deep insight into the losses through subsystems and actual performance. If the sole objective of optimization of heat recovery steam generator is to increase the exergetic efficiency or minimizing the exergy losses then it leads to the very high cost of power which is not acceptable. The exergo-economic analysis has been carried to find the cost flow from each subsystem involved to the combined power cycles. Thus the second law of thermodynamics combined with economics represents a very powerful tool for the systematic study and optimization of combined power cycles. Optimization studies have been carried out to evaluate the values of decision parameters of heat recovery steam generator for optimum exergetic efficiency and product cost. Genetic algorithm has been utilized for multi-objective optimization of this complex and nonlinear system. Pareto fronts generated by this study represent the set of best solutions and thus providing a support to the decision-making.

scholarly journals Gas Turbine Heat Recovery Steam Generators for Combined Cycles Natural or Forced Circulation Considerations

1988 ◽  
Author(s):  
Akber Pasha
Keyword(s):  
Gas Turbine ◽  
Steam Generator ◽  
Heat Recovery ◽  
Power Plants ◽  
Natural Circulation ◽  
Combined Cycle ◽  
Heat Recovery Steam Generator ◽  
Steam Generators ◽  
Forced Circulation ◽  
Gas Turbine Exhaust

In recent years the combined cycle has become a very attractive power plant arrangement because of its high cycle efficiency, short order-to-on-line time and flexibility in the sizing when compared to conventional steam power plants. However, optimization of the cycle and selection of combined cycle equipment has become more complex because the three major components, Gas Turbine, Heat Recovery Steam Generator and Steam Turbine, are often designed and built by different manufacturers. Heat Recovery Steam Generators are classified into two major categories — 1) Natural Circulation and 2) Forced Circulation. Both circulation designs have certain advantages, disadvantages and limitations. This paper analyzes various factors including; availability, start-up, gas turbine exhaust conditions, reliability, space requirements, etc., which are affected by the type of circulation and which in turn affect the design, price and performance of the Heat Recovery Steam Generator. Modern trends around the world are discussed and conclusions are drawn as to the best type of circulation for a Heat Recovery Steam Generator for combined cycle application.

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