Steam Cycle Regeneration Influence on Combined Gas-Steam Power Plant Performance

1985 ◽  
Vol 107 (3) ◽  
pp. 574-581 ◽  
Author(s):  
G. Cerri ◽  
A. Colage´
Keyword(s):  
Gas Turbine ◽  
Firing Temperature ◽  
Positive Influence ◽  
Combined Cycle ◽  
Point Of View ◽  
Plant Performance ◽  
Inlet Temperature ◽  
Efficiency Gain ◽  
Steam Power ◽  
Steam Cycle

The influence of steam cycle regeneration on combined plant performance has been analyzed from the thermodynamic point of view. A mathematical model has been developed and calculations have been performed according to a cycle analysis criterion. The higher the number of extractions the lower the relative efficiency gain. The influence of the intermediate feedwater temperatures is very small when these temperatures are slightly changed in relation to the equally spaced values. Results are given for a gas turbine firing temperature equal to 1000°C. They show a positive influence on combined cycle efficiency for small regeneration degrees. Gas turbine firing temperature in the range of 800–1400°C has been considered. The influence of the economizer inlet temperature lower limit is shown.

Advanced and Transformational Hydrogen Turbines for Integrated Gasification Combined Cycles

2016 ◽  
Author(s):  
Walter W. Shelton ◽  
Robin W. Ames ◽  
Richard A. Dennis ◽  
Charles W. White ◽  
John E. Plunkett ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Carbon Capture ◽  
Combined Cycle ◽  
Plant Performance ◽  
System Level ◽  
Inlet Temperature ◽  
Air Cooling ◽  
Reference Case ◽  
Advanced Technologies ◽  
Integrated Gasification

The U.S. Department of Energy’s (DOE) provides a worldwide leadership role in the development of advanced fossil fuel-based energy conversion technologies, with a focus on electric power generation with carbon capture and storage (CCS). As part of DOE’s Office of Fossil Energy, the National Energy Technology Laboratory (NETL) implements research, development, and demonstration (RD&D) programs that address the challenges of reducing greenhouse gas emissions. To meet these challenges, NETL evaluates advanced power cycles that will maximize system efficiency and performance, while minimizing CO2 emissions and the costs of CCS. NETL’s Hydrogen Turbine Program has sponsored numerous R&D projects in support of Advanced Hydrogen Turbines (AHT). Turbine systems and components targeted for development include combustor technology, materials research, enhanced cooling technology, coatings development, and more. The R&D builds on existing gas turbine technologies and is intended to develop and test the component technologies and subsystems needed to validate the ability to meet the Turbine Program goals. These technologies are key components of AHTs, which enable overall plant efficiency and cost of electricity (COE) improvements relative to an F-frame turbine-based Integrated Gasification Combined Cycle (IGCC) reference plant equipped with carbon capture (today’s state-of-the-art). This work has also provided the basis for estimating future IGCC plant performance based on a Transformational Hydrogen Turbine (THT) with a higher turbine inlet temperature, enhanced material capabilities, reduced air cooling and leakage, and higher pressure ratios than the AHT. IGCC cases from using system-level AHT and THT gas turbine models were developed for comparisons with an F-frame turbine-based IGCC reference case and for an IGCC pathway study. The IGCC pathway is presented in which the reference case (i.e. includes F-frame turbine) is sequentially-modified through the incorporation of advanced technologies. Advanced technologies are considered to be either 2nd Generation or Transformational, if they are anticipated to be ready for demonstration by 2025 and 2030, respectively. The current results included the THT, additional potential transformational technologies related to IGCC plant sections (e.g. air separation, gasification, gas cleanup, carbon capture, NOx reduction) are being considered by NETL and are topics for inclusion in future reports.

Effect of Bottoming Cycle Alternatives on the Performance of Combined Cycle

2003 ◽  
Author(s):  
R. Yadav
Keyword(s):  
Gas Turbine ◽  
Pressure Ratio ◽  
Positive Influence ◽  
Combined Cycle ◽  
Exhaust Temperature ◽  
Compressor Pressure Ratio ◽  
Topping Cycle ◽  
Steam Parameters ◽  
Cycle Efficiency ◽  
Steam Cycle

The increase in efficiency of combined cycle has mainly been caused by the improvements in gas turbine cycle efficiency. With the increase in firing temperature the exhaust temperature is substantially high around 873 K for moderate compressor pressure ratio, which has positive influence on steam cycle efficiency. Minimizing the irreversibility within the heat recovery steam generator HRSG and choosing proper steam cycle configuration with optimized steam parameters improve the steam cycle efficiency and thus in turn the combined cycle efficiency. In this paper, LM9001H gas turbine, a state of art technology turbine with modified compressor pressure ratio has been chosen as a topping cycle. Various bottoming cycles alternatives (sub-critical) coupled with LM9001H topping cycle with and without recuperation such as dual and triple pressure steam cycles with and without reheat have been chosen to predict the performance of combined cycle.

Enhancing Energy and Economic Performances of Combined Cycle Power Plants by Means of Gas-Cycle Regeneration

2014 ◽  
Author(s):  
Roberto Carapellucci ◽  
Lorena Giordano
Keyword(s):  
Gas Turbine ◽  
Power Plants ◽  
Waste Heat ◽  
Pressure Ratio ◽  
Unit Cost ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Efficiency Gain ◽  
Gas Power Plant

Efficiency improvement in the gas turbine sector has been mainly driven by increasing the turbine inlet temperature and compressor pressure ratio. For a fixed technology level, a further efficiency gain can be achieved through the utilization of waste thermal energy. Regeneration is an internal recovery technique that allows the reduction of heat input required at combustor, by preheating the air at compressor outlet. Under certain operating conditions, the temperature of exhaust gas leaving the regenerator is still enough high to allow the steam production via an heat recovery steam generator (HRSG). Regeneration in steam-gas power plants (CCGT) has the potential to enhance thermal efficiency, but reduces the margins for external recovery and then the bottoming steam cycle capacity. Moreover, the reduction of exhausts temperature at gas turbine outlet requires the reconsideration of HRSG operating parameters, in order to limit the increase of waste heat at the stack. The aim of this study is to explore the potential benefits that regeneration in the gas cycle gives on the whole steam-gas power plant. The extent of energy and economic performances improvement is evaluated, varying the gas turbine specifications and the layout and operating conditions of HRSG. Hence simple and regenerative configurations based on single and multi-pressure HRSG are compared, focusing on efficiency, specific CO2 emissions and unit cost of electricity (COE).

Investigation of the Bottoming Cycle for High Efficiency Combined Cycle Gas Turbine System With Supercritical Carbon Dioxide Power Cycle

2015 ◽  
Author(s):  
Seong Kuk Cho ◽  
Minseok Kim ◽  
Seungjoon Baik ◽  
Yoonhan Ahn ◽  
Jeong Ik Lee
Keyword(s):  
Gas Turbine ◽  
Flow Rate ◽  
High Efficiency ◽  
Waste Heat ◽  
Combined Cycle ◽  
Inlet Temperature ◽  
Turbine Inlet Temperature ◽  
Power Cycle ◽  
Turbine Inlet ◽  
Steam Cycle

The supercritical CO2 (S-CO2) power cycle has been receiving attention as one of the future power cycle technology because of its compact configuration and high thermal efficiency at relatively low turbine inlet temperature ranges (450∼750°C). Thus, this low turbine inlet temperature can be suitable for the bottoming cycle of a combined cycle gas turbine because its exhaust temperature range is approximately 500∼600°C. The natural gas combined cycle power plant utilizes mainly steam Rankine cycle as a bottoming cycle to recover waste heat from a gas turbine. To improve the current situation with the S-CO2 power cycle technology, the research team collected various S-CO2 cycle layouts and compared each performance. Finally, seven cycle layouts were selected as a bottoming power system. In terms of the net work, each cycle was evaluated while the mass flow rate, the split flow rate and the minimum pressure were changed. The existing well-known S-CO2 cycle layouts are unsuitable for the purpose of a waste heat recovery system because it is specialized for a nuclear application. Therefore, the concept to combine two S-CO2 cycles was suggested in this paper. Also the complex single S-CO2 cycles are included in the study to explore its potential. As a result, the net work of the concept to combine two S-CO2 cycles was lower than that of the performance of the reference steam cycle. On the other hand, the cascade S-CO2 Brayton cycle 3 which is one of the complex single cycles was the only cycle to be superior to the reference steam cycle. This result shows the possibility of the S-CO2 bottoming cycle if component technologies become mature enough to realize the assumptions in this paper.

scholarly journals Fuel-Flexible Combined Cycles for Utility Power and Cogeneration

1980 ◽  
Author(s):  
P. B. Roberts ◽  
T. E. Duffy ◽  
H. Schreiber
Keyword(s):  
Power Plant ◽  
Gas Turbine ◽  
Power Plants ◽  
Turbine Rotor ◽  
Combined Cycle ◽  
Inlet Temperature ◽  
Gas Temperature ◽  
Industrial Gas Turbine ◽  
Plant Efficiency ◽  
Steam Cycle

Two combustion turbine combined cycle power plants have been studied for performance and operating economics. Both power plants are in the size range that will be suitable for small utility application and use less than 106 GJ/hr (100 million Btu/hr). The Powerplant and Industrial Fuel Use Act of 1978 has exempted power plants of this size from the requirement to use coal. The first power plant is based on the Solar Turbines International (STI) Mars industrial gas turbine. The combined gas turbine/steam cycle is direct fired with No. 2 diesel fuel. A net plant efficiency of 39.7 percent (HHV) is obtained at the 11.56-mW growth rating of the Mars engine for a turbine rotor inlet temperature of 1331 K (1935 F). A total installed cost for the system is estimated to be within the band 545 to 660 $/kW. The second power plant is based on STI’s Centaur industrial gas turbine. The combined gas turbine/steam cycle is indirectly fired with solid fuel although it is intended that the installation can be initially fired with a liquid fuel. A net plant efficiency of 25.0 percent (HHV) is obtained burning Illinois No. 6 coal at a rating of 3.78 mW with a turbine inlet gas temperature of 1117 K (1550 F).

scholarly journals Thermodynamical Optimization of a Combined Cycle Plant Performance

1994 ◽  
Author(s):  
K. Sarabchi ◽  
G. T. Polley
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Performance Optimization ◽  
Pressure Ratio ◽  
Combined Cycle ◽  
Plant Performance ◽  
Inlet Temperature ◽  
Turbine Inlet Temperature ◽  
Turbine Inlet ◽  
Recovery Boiler

Computer modelling of Performance optimization was done to examine the effect of key operating variables like compressor pressure ratio, turbine inlet temperature, and recovery boiler pressure on performance parameters of a simple combined cycle and comparison was made to a simple gas turbine cycle. Both thermal efficiency and specific net work were examined as pressure ratio and recovery boiler pressure were varied for each turbine inlet temperature. Also careful consideration was given to admissible values of stack gas temperature, steam turbine outlet dryness fraction, and steam turbine outlet dryness fraction, and steam turbine inlet temperature. Specifically, it was shown that when we treat a combined cycle as an integrated system, efficiency optimization entails a pressure ratio below that suitable for simple gas turbine plant.

Steam Turbine Driving Compressor for Gas-Steam Combined Cycle Power Plant

2009 ◽  
Author(s):  
Wancai Liu ◽  
Hui Zhang
Keyword(s):  
Power Generation ◽  
Power Plant ◽  
Steam Turbine ◽  
Gas Turbine ◽  
Combined Cycle ◽  
Thermodynamic Process ◽  
Combined Cycle Power Plant ◽  
Steam Cycle

Gas turbine is widely applied in power-generation field, especially combined gas-steam cycle. In this paper, the new scheme of steam turbine driving compressor is investigated aiming at the gas-steam combined cycle power plant. Under calculating the thermodynamic process, the new scheme is compared with the scheme of conventional gas-steam combined cycle, pointing its main merits and shortcomings. At the same time, two improved schemes of steam turbine driving compressor are discussed.

scholarly journals Internal Combustion Steam Cycle (G.I.S.T. Cycle): Thermodynamical Feasibility and Plant Lay-Out Proposals

1997 ◽  
Author(s):  
C. Caputo ◽  
M. Gambini ◽  
G. L. Guizzi
Keyword(s):  
Natural Gas ◽  
Power Plants ◽  
Internal Combustion ◽  
Steam Flow ◽  
Inlet Temperature ◽  
Steam Boiler ◽  
Critical Approach ◽  
Steam Power ◽  
Steam Power Plants ◽  
Steam Cycle

In this paper a new kind of steam cycle provided with internal combustion is proposed. The internal combustion of natural gas and compressed air inside the steam flow has been conceived to carry out a steam heating (SH a/o RH) until TIT (Turbine Inlet Temperature) much higher than those of the conventional steam power plants. By this internal combustion it seems possible to overcome the present limits to TIT in steam plants which are, as known, especially related to the technological problems of the superheater tube materials in the conventional external combustion steam boilers. The proposed cycle has been named with the acronym GIST (Gas Injection STeam) since the hot gases resulting from a combustion close to stechiometric conditions are injected inside the steam flow. This paper provides a first critical approach to these new kinds of thermodynamical cycles. At the first the thermodynamical and technological problems related to the combustion inside steam are explained and discussed. Then, different plant lay-out solutions are proposed with a critical discussion on their overall performance. At the last two GIST solution have been defined that seem very interesting: the first is an hybrid plant scheme (i.e. provided with multi-fuel supply) which involves performances higher than conventional steam power plants (net electric efficiency of about 47%); the second is a plant scheme with full natural gas supply (i.e. without multi-fuel steam boiler) wich involves very relevant performances (net electric efficiency of about 57%).

scholarly journals Current Status of Ceramic Gas Turbine (CGT302)

1998 ◽  
Author(s):  
Hirotake Kobayashi ◽  
Tetsuo Tatsumi ◽  
Takashi Nakashima ◽  
Isashi Takehara ◽  
Yoshihiro Ichikawa
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Technology Development ◽  
Development Program ◽  
Point Of View ◽  
Current Status ◽  
Fiscal Year ◽  
Inlet Temperature ◽  
Development Organization ◽  
New Energy

In Japan, from the point of view of energy saving and environmental protection, a 300kW Ceramic Gas Turbine (CGT) Research and Development program started in 1988 and is still continuing as a part of “the New Sunshine Project” promoted by the Ministry of International Trade and Industry (MITT). The final target of the program is to achieve 42% thermal efficiency at 1350°C of turbine inlet temperature (TIT) and to keep NOx emissions below present national regulations. Under contract to the New Energy and Industrial Technology Development Organization (NEDO), Kawasaki Heavy Industries, Ltd. (KHI) has been developing the CGT302 with Kyocera Corporation and Sumitomo Precision Products Co., Ltd. By the end of the fiscal year 1996, the CGT302 achieved 37.0% thermal efficiency at 1280°C of TIT. In 1997, TIT reached 1350°C and a durability operation for 20 hours at 1350°C was conducted successfully. Also fairly low NOx was proved at 1300°C of TIT. In January 1998, the CGT302 has achieved 37.4% thermal efficiency at 1250°C TIT. In this paper, we will describe our approaches to the target performance of the CGT302 and current status.

Sign in / Sign up

Export Citation Format

Share Document