-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
1/15
Introduction to Combine Cycle
Power PlantBy
Leelananda Pilanawithana
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
2/15
Power plants
Categorized by functional type Base load
Peak load and emergency
Base load
Run continuously, stop only for maintenance. Generatepower most in any given year.
Have lowest operating cost.
Its type
High efficient combined cycle plants fueled by natural gasor liquid fuel
Nuclear Power Plants
Conventional steam power plants fueled primarily bycoal or fernours oil
Hydropower plants
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
3/15
Peak load and emergency
Run during peak load demand period or an emergency.
Operating cost is high, but cheap to built.
Fast start and loading.
Type
Open Cycle (Simple cycle) gas turbine plant.
Diesel engine plants.
Hydropower plant
Power plants
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
4/15
Definition
Combine
When several different things add together
Cycle
Process is repeated or moving around a circle.
In Thermodynamic point of view,Rankine,
Diesel,
Otto ,
Carnot,
Brayton,
are some of the thermodynamic cycles.
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
5/15
Definition
Those cycles are always associated with one of the
two type of combustion processes.
Internal Combustion
Gas Turbines,
Diesel engines,
Gasoline engines
External Combustion
Steam Engines (Boiler and steam turbine)
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
6/15
Cycle Definition Combine Cycle
Employ more than one thermodynamic cycles.
Brayton cycle,
Rankine cycle.
Improve the simple Brayton cycle efficiency by capturing
wasted energy in Brayton cycle and use it inR
anking Cycle. Brayton cycle,
Engine used extensively is a Gas Turbine
utilize only a portion of the energyfrom the fuel that is being used Open cycle or
Reminder if not recovered is wasted. Simple cycle
Open cycle
Configuration
Combine cycle
Configuration
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
7/15
Gas Turbine and its Major components
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
8/15
Cycle Definition
Rankine cycle
Engine used is Heat Recovery Boiler (HRSG) plus Steam
Turbine.
Basic equipment arrangement Temperature Entropy Diagram
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
9/15
Heat Recovery Steam Generator
Flue Gas in
Heat
Exchanger
Modules
DrumsDrums
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
10/15
Steam Turbine
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
11/15
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
12/15
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
13/15
Advantages of Combine Cycle Power Plant
Low installation cost / MW
High efficiency among all practical power cycles.
Low auxiliary power consumption/MW (2 3%)
Less manpower/MW ratio. High reliability and availability.
Clean operating Condition.
Less Gestation period.
Fast starting characteristics.
Less water requirement.
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
14/15
Less pollution problems.
Flexibility in locating power plant.
Fuel flexibility.
Less space requirement.
Gas turbine can be operated as peak load plant and
Steam turbine as base load plant by supplementary
firing in HRSG unit
Advantages of Combine Cycle Power Plant
-
8/3/2019 Introduction to Combine Cycle Power Plant 1 - By Leel
15/15
Need good quality fuel specifically low sulfur,
vanadium and lead content .
Fuel treatment process is costly. GT performance severely deteriorate with
ambient temperature.
High Nox pollutant. GT life is less due to corrosion problems.
Uneconomical partial load operation.
Disadvantages of Combine Cycle Power Plant
