Advanced Combined Cycle Alternatives With the Latest Gas Turbines

1996 ◽  
Author(s):  
P. J. Dechamps
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Power Plants ◽  
Combined Cycle ◽  
Point Of View ◽  
Specific Work ◽  
Turbine Cooling ◽  
Exhaust Temperature ◽  
Industrial Gas Turbine

The last decade has seen remarkable improvements in industrial gas turbine size and performances. There is no doubt that the coming years are holding the promises of even more progress in these fields. As a consequence, the fuel utilization achieved by combined cycle power plants has been steadily increased. This is however also because of the developments in the heat recovery technology. Advances on the gas turbine side justify the development of new combined cycle schemes, with more advanced heat recovery capabilities. Hence, the system performance is spiralling upwards. In this paper, we look at some of the heat recovery possibilities with the newly available gas turbine engines, characterized by a high exhaust temperature, a high specific work, and the integration of some gas turbine cooling with the boiler. The schemes range from classical dual pressure systems, to triple pressure systems with reheat in supercritical steam conditions. For each system, an optimum set of variables (steam pressures, etc) is proposed. The effect of some changes on the steam cycle parameters, like increasing the steam temperatures above 570°C are also considered. Emphasis is also put on the influence of some special features or arrangements of the heat recovery steam generators, not only from a thermodynamic point of view.

Advanced Combined Cycle Alternatives With the Latest Gas Turbines

1998 ◽  
Vol 120 (2) ◽  
pp. 350-357 ◽  
Author(s):  
P. J. Dechamps
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Power Plants ◽  
Combined Cycle ◽  
Point Of View ◽  
Specific Work ◽  
Turbine Cooling ◽  
Exhaust Temperature ◽  
Industrial Gas Turbine

The last decade has seen remarkable improvements in industrial gas turbine size and performances. There is no doubt that the coming years are holding the promise of even more progress in these fields. As a consequence, the fuel utilization achieved by combined cycle power plants has been steadily increased. This is, however, also because of the developments in the heat recovery technology. Advances on the gas turbine side justify the development of new combined cycle schemes, with more advanced heat recovery capabilities. Hence, the system performance is spiraling upward. In this paper, we look at some of the heat recovery possibilities with the newly available gas turbine engines, characterized by a high exhaust temperature, a high specific work, and the integration of some gas turbine cooling with the boiler. The schemes range from classical dual pressure systems, to triple pressure systems with reheat in supercritical steam conditions. For each system, an optimum set of variables (steam pressures, etc.) is proposed. The effect of some changes on the steam cycle parameters, like increasing the steam temperatures above 570°C are also considered. Emphasis is also put on the influence of some special features or arrangements of the heat recovery steam generators, not only from a thermodynamic point of view.

On the Economics of the Use of Biomass Fuels in Gas Turbine Cycles: Gasification vs. Externally Firing

2004 ◽  
Author(s):  
Sandro Barros Ferreira ◽  
Pericles Pilidis
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Technological Development ◽  
Pilot Scale ◽  
Combined Cycle ◽  
Point Of View ◽  
Turbine Engine ◽  
Current Technology ◽  
Integrated Gasification

The use of biomass as gas turbine combined cycle fuels is broadly seen as one of the alternatives to diminish greenhouse gas emissions, mainly CO2, due to the efficiency delivered by such systems and the renewable characteristic of biomass itself. Integrated gasification cycles, BIGGT, are the current technology available; however the gasification system severely penalizes the power plant in terms of efficiency and demands modifications in the engine to accommodate the large fuel mass flow. This gives an opportunity to improvements in the current technologies and implementation of new ones. This paper intends to analyze new alternatives to the use of solid fuels in gas turbines, from the economical point of view, through the use of external combustion, EFGT, discussing its advantages and limitations over the current technology. The results show that both EFGT and BIGGT technologies are economically competitive with the current natural gas fired gas turbines. However, BIGGT power plants are still in pilot scale and the EFGT plants need further technological development. Thermodynamically speaking, the inherently recuperative characteristic of the EFGT gas turbine engine makes it well suited to the biomass market. The thermal efficiency of this cycle is higher than the BIGGT system. Furthermore, its fuel flexibility and negligible pre-treatmet is another advantage that makes it an interesting option for the Brazilian market.

scholarly journals Axial compressor fouling detection for gas turbine driven gas compression unit

2019 ◽  
Vol 15 (3) ◽  
pp. 1257
Author(s):  
Nurlan Batayev
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Detection System ◽  
Axial Compressor ◽  
Compressor Blades ◽  
Exhaust Temperature ◽  
Gas Compression ◽  
Compressor Power ◽  
Industrial Gas Turbine

<span>One of the main reasons of the performance degradation of gas turbines is the axial compressor fouling due to air pollutants. Considering the fact that the fouling leads to high consumption of fuel, reducing of the axial compressor’s discharge air pressure and increasing of the exhaust temperature, thus designing a compressor degradation detection system will allow prevent such issues. Many gas turbine plants lose power due to dirty axial compressor blades, which can add up to 4% loss of power. In case of power plants, the power loosing could be observed by less megawatts produced by generator. But in case of gas compression stations the effect of power loosing could not be quickly detected, because there is not direct measurement of the discharge power produced by gas turbine. This article represents technique for detection of gas turbine axial compressor degradation in case of gas turbine driven natural gas compression units. Calculation of the centrifugal gas compressor power performed using proven methodology. Approach for evaluation of the gas turbine performance based on machine learning prediction model is shown.  Adequacy of the model has been made to three weeks’ operation data of the 10 Megawatt class industrial gas turbine.</span>

Modified Rankine HRSG Beats Triple-Pressure System

1996 ◽  
Author(s):  
Peter Eisenkolb ◽  
Martin Pogoreutz ◽  
Hermann Halozan
Keyword(s):  
Heat Transfer ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Power Plants ◽  
Fossil Fuels ◽  
Combined Cycle ◽  
Exhaust Gas ◽  
Pressure System ◽  
Exergy Losses

Gas-fired combined cycle power plants (CCP) are presently the most efficient systems for producing electricity with fossil fuels. Gas turbines have been and are being improved remarkably during the last years; presently they achieve efficiencies of more than 38% and gas turbine outlet temperatures of up to 610°C. These high outlet temperatures require modifications and improvements of heat recovery steam generators (HRSG). Presently dual pressure HRSGs are most commonly used in combined cycle power stations. The next step seems to be the triple-pressure HRSG to be able to utilise the high gas turbine outlet temperatures efficiently and to reduce exergy losses caused by the heat transfer between exhaust gas and the steam cycle. However, such triple-pressure systems are complicated considering parallel tube bundles as well as start up operation and load changes. For that reason an attempt has been made to replace such multiple pressure systems by a modified Rankine cycle with only a single-pressure level. In the case of the same total heat transfer surfaces this innovative single-pressure system achieves approximately the same efficiency as the triple-pressure system. By optimising the heat recovery from the exhaust gas to the steam/water cycle, i.e. minimising exergy losses, the stack temperature is much higher. Increasing the heat transfer surfaces means a decrease of the stack temperature and a further improvement of the overall CCP-efficiency. Therefore one has to be aware that the proposed system offers advantages not only in the case of a foreseeable increase of gas turbine outlet temperatures but also for presently available gas turbines. Using existing highly efficient gas turbines and subcritical steam conditions, power plants with this proposed Eisenkolb Single Pressure (ESP_CCP) heat recovery steam generator achieve thermal efficiencies of about 58.7% (LHV).

Integration of Modern F, G, H and J Class in Combined Cycle Applications: An EPC Contractor Perspective

2016 ◽  
Author(s):  
Justin Zachary ◽  
Vinod Kallianpur ◽  
Byungsik So
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Traditional Approach ◽  
Combined Cycle ◽  
Reference Architecture ◽  
Design Concepts ◽  
Industrial Gas Turbines ◽  
Turbine Design ◽  
Industrial Gas Turbine

The traditional approach for developing new and upgrade model large frame industrial gas turbines is changing rather dramatically. Large industrial gas turbine design evolutions have typically been built around a basic core design concept that remained unchanged. The departure from tradition has been, in some cases, sparked by the merger between erstwhile competitors. Thus the models that follow a merger benefit from leveraging the best of available knowledge from both companies: specialized design methods, manufacturing practices, materials, combustion, etc. Another recent trend in GT development is to transfer select portions of design concepts and related experience, and integrate that knowledge into a new model. Both these trajectories of development involve some changes to the core design reference architecture: e.g. number of rows in turbine section, rotor design architecture, flow path shape, blade locking approach, exhaust diffuser, inlet scroll, etc., and needing more attention to detail by the EPC for being able to meet the customer expectations for life cycle costs, performance degradation, reliability and availability. The expanded technical capability of the OEMs to accelerate new technical innovations for propelling the next economic growth engine is indeed a very exciting prospect for EPC contractors. Already, modern “H” and “J” class gas turbines are commercially available for over 60 per cent net efficiency in combined cycle power plant application. This paper shares an EPC contractor’s experience in developing Combined Cycle Power Plants with two advanced commercially available gas turbine models in Korea (Mitsubishi’s M501J model) and Malaysia (Siemens SGT. 5-8000H model).

Conserving Energy by the Efficient Use of the Industrial Gas Turbine

1982 ◽  
Author(s):  
D. M. S. Lightbody
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Combined Cycle ◽  
Market Forces ◽  
Specific Work ◽  
Steam Turbines ◽  
The Uk ◽  
Industrial Gas Turbine ◽  
Cycle Efficiency

The paper covers the basic thermodynamics of the combined cycle concept and illustrates that energy conservation is possible by coupling the Joule and Rankine cycles. It discusses the optimisation of steam conditions and outlines the concept of the unfired combined cycle. “Carnot efficiency” and “pinch points” are shown to be important as is the concept of “specific work” as it relates to the gas turbine in arriving at the best overall cycle efficiencies. The importance of the efficiency characteristic of the steam turbine is emphasised and it is shown that this characteristic will determine the overall cycle efficiency. It is suggested that steam turbine manufacturers should design and develop steam turbines to match the advanced gas turbines available to-day and so enchance the overall efficiency which can presently be obtained from to-day’s combined cycle. Market forces will tend to bring this about as evidenced by the growing interest being shown in this concept both in the UK and Europe.

Commercialization and Fleet Experience of the 7/9HA Gas Turbine Combined Cycle

2019 ◽  
Author(s):  
Christian Vandervort ◽  
David Leach ◽  
David Walker ◽  
Jerry Sasser
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
High Efficiency ◽  
Operating Experience ◽  
Combined Cycle ◽  
Lessons Learned ◽  
Operational Flexibility ◽  
Industrial Gas Turbine ◽  
Cycle Efficiency

Abstract The power generation industry is facing unprecedented challenges. High fuel costs and increased penetration of renewable power have resulted in greater demand for high efficiency and operational flexibility. Imperatives to reduce carbon footprint place an even higher premium on efficiency. Power producers are seeking highly efficient, reliable, and operationally flexible solutions that provide long-term profitability in a volatile environment. New generation must also be cost-effective to ensure affordability for both domestic and industrial consumers. Gas turbine combined cycle power plants meet these requirements by providing reliable, dispatchable generation with a low cost of electricity, reduced environmental impact, and broad operational flexibility. Start times for large, industrial gas turbine combined cycles are less than 30 minutes from turning gear to full load, with ramp rates from 60 to 88 MW/minute. GE introduced the 7/9HA industrial gas turbine product portfolio in 2014 in response to these demands. These air-cooled, H-class gas turbines (7/9HA) are engineered to achieve greater than 63% net combined cycle efficiency while delivering operational flexibility through deep, emission-compliant turndown and high ramp rates. The largest of these gas turbines, the 9HA.02, is designed to exceed 64% combined cycle efficiency (net, ISO) in a 1×1, single-shaft (SS) configuration. As of December 2018, a total of 32 7/9HA power plants have achieved COD (Commercial Operation Date) while accumulating over 220,000 hours of operation. These plants operate across a variety of demand profiles including base load and load following (intermediate) service. Fleet leaders for both the 7HA and 9HA have exceeded 12,000 hours of operation, with multiple units over 8,000 hours. This paper will address four topics relating to the HA platform: 1) gas turbine product technology, 2) gas turbine validation, 3) integrated power plant commissioning and operating experience, and 4) lessons learned and fleet reliability.

Performance Charateristics of Advanced Gas Turbine Cogeneration Power Plants

2005 ◽  
Author(s):  
Meherwan P. Boyce
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Firing Temperature ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Power Plants ◽  
Pressure Ratio ◽  
Combined Cycle ◽  
Air Filter ◽  
Cycle Efficiency

The performance analysis of the new generation of Gas Turbines in combined cycle operation is complex and presents new problems, which have to be addressed. The new units operate at very high turbine firing temperatures. Thus variation in this firing temperature significantly affects the performance and life of the components in the hot section of the turbine. The compressor pressure ratio is high which leads to a very narrow operation margin, thus making the turbine very susceptible to compressor fouling. The turbines are also very sensitive to backpressure exerted on them by the heat recovery steam generators. The pressure drop through the air filter also results in major deterioration of the performance of the turbine. The performance of the combined cycle is also dependent on the steam turbine performance. The steam turbine is dependent on the pressure, temperature, and flow generated in the heat recovery steam generator, which in turn is dependent on the turbine firing temperature, and the air mass flow through the gas turbine. It is obvious that the entire system is very intertwined and that deterioration of one component will lead to off-design operation of other components, which in most cases leads to overall drop in cycle efficiency. Thus, determining component performance and efficiency is the key to determining overall cycle efficiency. Thermodynamic modeling of the plant with individual component analysis is not only extremely important in optimizing the overall performance of the plant but in also determining life cycle considerations.

Part-Load Operation of Combined Cycle Plants With and Without Supplementary Firing

1995 ◽  
Vol 117 (3) ◽  
pp. 475-483 ◽  
Author(s):  
P. J. Dechamps ◽  
N. Pirard ◽  
Ph. Mathieu
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Power Plants ◽  
Combined Cycle ◽  
Steam Generators ◽  
Part Load ◽  
Inlet Guide Vanes ◽  
Steam Plant

The design point performance of combined cycle power plants has been steadily increasing, because of improvements both in the gas turbine technology and in the heat recovery technology, with multiple pressure heat recovery steam generators. The concern remains, however, that combined cycle power plants, like all installations based on gas turbines, have a rapid performance degradation when the load is reduced. In particular, it is well known that the efficiency degradation of a combined cycle is more rapid than that of a classical steam plant. This paper describes a methodology that can be used to evaluate the part-load performances of combined cycle units. Some examples are presented and discussed, covering multiple pressure arrangements, incorporating supplemental firing and possibly reheat. Some emphasis is put on the additional flexibility offered by the use of supplemental firing, in conjunction with schemes comprising more than one gas turbine per steam turbine. The influence of the gas turbine controls, like the use of variable inlet guide vanes in the compressor control, is also discussed.

scholarly journals Thermodynamic Analysis of Different Configurations of Combined Cycle Power Plants

2015 ◽  
Vol 5 (2) ◽  
pp. 89
Author(s):  
Munzer S. Y. Ebaid ◽  
Qusai Z. Al-hamdan
Keyword(s):  
Gas Turbine ◽  
Power Plants ◽  
Combined Cycle ◽  
Cycle Performance ◽  
Maximum Efficiency ◽  
Specific Work ◽  
Slight Effect ◽  
Turbine Engine ◽  
Gas Turbine Cycle ◽  
Cycle Efficiency

<p class="1Body">Several modifications have been made to the simple gas turbine cycle in order to increase its thermal efficiency but within the thermal and mechanical stress constrain, the efficiency still ranges between 38 and 42%. The concept of using combined cycle power or CPP plant would be more attractive in hot countries than the combined heat and power or CHP plant. The current work deals with the performance of different configurations of the gas turbine engine operating as a part of the combined cycle power plant. The results showed that the maximum CPP cycle efficiency would be at a point for which the gas turbine cycle would have neither its maximum efficiency nor its maximum specific work output. It has been shown that supplementary heating or gas turbine reheating would decrease the CPP cycle efficiency; hence, it could only be justified at low gas turbine inlet temperatures. Also it has been shown that although gas turbine intercooling would enhance the performance of the gas turbine cycle, it would have only a slight effect on the CPP cycle performance.</p>

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