Advanced Technology Gas Turbines and Planned Optimization of Combined Cycle Power Plants

November 9 - 13, 2009
Institute of Mechanical Engineers
One Bird Cage Walk London U.K.

DAY 1

Overview of Combined Cycle Power Plants
Various types and sizes of combined cycle power plants used in the power and petrochemical industry are discussed. Operation characteristics of the plants to operate at part load while maximizing efficiency is emphasized both for combined cycle applications and petrochemical compressor drives.

Cycle Analysis and Power Augmentation
Analysis of various types of cycles including intercooled, reheat and regeneration cycles, combined cycles, cogeneration cycles and optimization of the cycle based on the performance of the various components will be discussed.

Power Augmentation
Methods of increasing cycle efficiency and the output power are studied, such as inlet evaporative and refrigeration cooling, interstage cooling, water and steam injection. State of the art developments in gas turbine technology are reviewed, especially the characteristics of operating gas turbines over a large operating range while maximizing the performance of the entire system.

High Efficiency Maintenance
Maintaining high efficiency at part load operations is a challenge and thus this will include the examination of techniques which will allow the gas turbines at off design loads to operate at its maximum, within the entire plant system ensuring high operating efficiency of all components.

Performance and Mechanical Equipment Standards
The ASME and API standards applicable to the various pieces of Machinery will be discussed

DAY 2

Advanced Gas Turbine Characteristics
This day is devoted to the examination of design changes in Advanced Gas Turbines, from changes in cycle characteristics, to changes in design characteristics of compressor and turbine blading, high inlet temperatures, increased pressure ratios, new DLN combustors for low NOx characteristics

Axial Flow Compressors and Turbines
Key aero-thermodynamic considerations of axial and centrifugal compressors are covered including the effect of surge on gas turbine operation. This section also covers mechanical, performance and aerodynamic aspects of gas turbines, including new cooling schemes for gas turbines to operate at turbine inlet temperatures of 1350ºC -1450ºC.

Combustors and Fuels
A description of combustor types, chamber design, fuel atomization, ignition and combustor arrangements are presented. Dry low NOx combustors and their problems with “Flash Back” will be discussed. Fuel treatment of natural gas and other fuels before using them in the gas turbine will be studied, to ensure that the turbine combustion will meet specifications covering emissions and ensuring maximum combustion liner life.

Materials Metallurgy and Coatings
This covers the material aspects of gas turbine blading, turbine wheel alloys, and future materials are discussed. Common failure modes and cases are presented. Coatings as applied to both the Hot Section Components and the compressor will also be discussed under this section.

DAY 3

Steam Turbine Technology
The design of the steam turbines will be undertaken in this section. The design of the high pressure turbine, which is usually an impulse turbine, will be discussed and the IP and LP turbines, which are usually reaction turbines, will also be studied separately

HRSG Technology
The study of the HRSG will be undertaken in conjunction with the feed water heaters, dearators, and economizers, plus the preheaters, evaporators, and superheaters of each stage. A study of the temperature distribution as a function of the heat input is also studied with various optimization techniques to assure maximum effectiveness of the HRSG.

Condensers
A study of the condensers and the computation of the degree of fouling will be examined. The study will include techniques of computing the fouling in the tubes and the quality of the steam entering the unit. The effect of the fouling on the condenser pressure and the effect of that pressure on the entire power output of the plant.

Feed Water Pumps
The design characteristic of the feed water pumps will be undertaken. Most of these pumps have centrifugal impellers and so a study of the flow in these impellers will be conducted and the performance characteristics of these pumps will be studied.

DAY 4

Instrumentation and Condition Monitoring
An overview of techniques and instrumentation used for monitoring and diagnostics of gas turbines is presented. Techniques covering diagnostics based on performance and mechanical characteristics will be discussed. Systems for gas turbines will be analyzed.

Case Histories
Case histories of various types of turbine failures and maintenance problems of gas turbines used in various operations from power plants to offshore compressor installations are discussed. The student is acquainted with the many types of failures that occur in gas turbines, and to the reasons that cause the problems.

DAY 5

SPECIAL SESSION
Combined Cycle Plant Performance
Performance computations will be as per various ASME PTC Codes. Techniques for computing performance of the advanced gas turbines in design and off design operation and in combined cycle modes will be studied. Most new advanced gas turbines 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 turbine is also very sensitive to backpressure exerted on it by the heat recovery steam generator. The pressure drop through the air filter and dirty compressors also results in major deterioration of the performance of the turbine, thus emphasis will be placed on this computation.

Steam Turbine computations will also be carried out in detail. Workings of the Mollier Charts and the Steam Tables will be used to compute performance of the Steam Tables. Correction factors of the steam turbine will also be discussed.

It is suggested that attendees bring with them their lap top computers so that sample computations can be carried out in conjunction with the instructor.