INDUSTRIAL RESOURCES, INC Power Plant Fundamentals Training Module 2 Power Plant Theory
Power Plant Fundamentals Training This program is designed to provide you with a fundamental understanding of power plant operation. Some of the information may not apply to your specific facility but is provided to give you an overall picture of power plants used in the power industry. Industrial Resources, Inc. A Training Services Company
OBJECTIVES Demonstrate Basic Knowledge of: Energy Conversion Fluid Properties and Fluid Flow Pressure Temperature and Heat Thermodynamics Unit Energy Conversion Processes Water/Steam Properties Steam Applications Steam Tables and Their Uses Plant Performance
Energy Conversion Fuel and Air (Chemical Energy) to Thermal Energy (Heat) Module 8, Fuels and Combustion Heat Transfer to Water and Steam Module 9, Boilers Thermal Energy to Mechanical Energy (Torque) Module 10, Turbines Torque to Electrical Energy Module 13, Power Generation
Heat Transfer
Question 1 The energy conversion that occurs in the Boiler Furnace is chemical energy into. Electrical Energy Thermal Energy (Heat) Mechanical Energy (Torque) No energy conversion occurs in the Boiler Furnace
Question 1 Answer If you said Electrical, you were right. We want to make electricity so that we can sell it to customers.
Fluid Properties and Flow What Is a Fluid? How do we describe Fluids? What are some Fluid Properties? How do Fluids flow?
Atoms and Elements Atom smallest piece of an element Element a type of substance Only about 100 elements But millions of combinations of them Examples of elements are:
Before we go any further, you might be thinking: How big is an atom? Suppose you had 1 pound of iron (Fe). How many atoms do you think are in that pound of iron? Actually, there are about 5 million billion billion atoms in that pound, or 5,000,000,000,000,000,000,000,000 atoms
Compound Combination of Atoms Millions of them, including: Water Carbon Dioxide Sulfuric Acid
Molecule smallest piece of a compound that is still the compound. If we broke down a molecule, we get atoms that make up that compound.
Chemical Reaction forming compounds from atoms or other compounds
Physical Properties Describe by Weight Describe by Temperature Describe by How Substance Flows Think about what State Substance is in States: Solid Liquid Gas
Solid Molecules in fixed positions Example: Ice is solid form of water If Temperature increases enough, melts
Liquid As add Heat, Liquid expands. Add enough Heat, Liquid starts to turn to Gas. Molecules not in fixed positions, but close Takes shape of container Example: Ice is solid form of water
Gas Molecules not close, spread out Fills container Example: Steam is gaseous form of water
What Is a Fluid? Something that Flows Liquid or Gas Can Turn Solid into Liquid Examples: Melting Iron Dry Ice is solid CO 2 Liquid CO 2 in Fire Extinguishers
Describing Fluids Pressure how much molecules try to keep away from each other Temperature how much molecules vibrate Heat Content amount of Thermal Energy in Fluid Density Mass of Fluid per unit Volume Viscosity Resistance to flow
Question 2 A Fluid is either a or a. Solid, Liquid Liquid, Gas Solid, Gas A fluid is ONLY a liquid.
Question 2 Answer If you said Liquid, Gas, you were right. A fluid flows and a solid does not flow, unless made into a liquid or a gas.
Question 3 Which state of matter has molecules close together, but free to move relative to each other and takes the shape of its container? Solid Liquid Gas Solid or liquid
Question 3 Answer If you said Liquid, you were right.
Pressure Force per unit Area
Atmospheric Pressure 14.696 pounds per square inch (psi)
Barometer Maintaining a Vacuum is Difficult, So We Don t
Absolute Pressure Absolute Pressure psia bar 14.7 psia Scale Atmospheric Pressure Absolute 0 Pressure
Absolute Pressure Gauge Pressure 34.7 psia 20 psig Gauge Pressure Scale psia bar 14.7 psia 0 psig psig barg Atmospheric Pressure Absolute 0 Pressure
Absolute Pressure Gauge Pressure 34.7 psia 20 psig Vacuum Scale psia bar 14.7 psia 0 psig psig barg Atmospheric Pressure 2 in. Hg Vacuum In. Hg vac is 1 psi In. Hg abs. Back- Pressure Absolute 0 Pressure
Fluid Pressure Some Units gauges are Gauge have Pressure more than units one scale
Question 4 A device that measures atmospheric pressure is called a. Pressure Gauge Barometer Pressure Scale Vacuum Gauge
Question 4 Answer If you said Barometer, you were right.
Question 5 A fluid pressure of 40 psig has an absolute pressure of psia (on a day when atmospheric pressure is 14.7 psia). 0 25.3 40 54.7
Question 5 Answer If you said 54.7, you were right. You add the atmospheric pressure to the gauge pressure to get absolute pressure. In this case, that is 14.7 + 40 = 54.7
Temperature and Heat
Don t Confuse Temperature and Heat Temperature Vibration of Molecules Heat Thermal Energy contained in Molecules Enthalpy measure of Heat Content Enthalpy affected by Temperature, Pressure, Volume, and State of Molecules Water at boiling temperature has the same temperature as steam at boiling temperature, but a different heat content
Unit of Heat Content - Btu One British Thermal Unit (BTU) is about one wooden match in energy
Formula for Enthalpy Enthalpy Enthalpy (H) = Internal Energy (U) + Flow Work (PV)/BTU Constant (J) Internal Energy - sum of the energy of vibration due to temperature of all of the molecules of a substance Flow Work (PV/J) - energy contained in a substance due to its pressure and volume J is a constant value that allows Enthalpy to be stated in BTUs
Temperature and Heat Add heat to boil water, but temperature does not change Internal Energy goes up due to change of state Flow work goes up due to change of volume Over 970 Btus to boil 1 pound of water at 14.7 psia
Fahrenheit (degf) Celsius (degc) Boiling Temperature 212 degf 100 degc Temperature Scales 180 degf 100 degc 9 degf = 5 degc 32 degf 0 degc Freezing Temperature
Plant Temperature Gauges
Question 6 Internal Energy (U) plus Flow Work (PV/J) equals (H). Temperature Enthalpy Entropy Torque
Question 6 Answer If you said enthalpy, you were right. The enthalpy is the heat content of the molecules in a fluid.
Question 7 Boiler temperature of 212 degf is indicated in Celsius as degc. 0 32 100 212
Question 7 Answer If you said 100, you were right.
Thermodynamics Thermo heat dynamics motion General Energy Equation describes what each Component does
General Energy Equation Heat Heat In Positive Potential Energy Enthalpy Kinetic Energy Equipment Potential Energy Enthalpy Kinetic Energy Work Need Moving Parts for Work to occur Work Out Positive
General Energy Equation Heat Potential Energy Enthalpy Kinetic Energy Equipment Potential Energy Enthalpy Kinetic Energy Work Potential Energy energy due to position Kinetic Energy energy due to Speed Both small amounts, so can ignore them
General Energy Equation - Boiler Heat Enthalpy Boiler Enthalpy
General Energy Equation - Turbine Enthalpy Turbine Enthalpy Work
Other Parts In Time
Question 8 In analyzing equipment using the General Equation, which of the following is correct for a piece of equipment being analyzed? Heat Out Positive, Work Out Positive Heat In Positive, Work Out Positive Heat Out Positive, Work In Positive Heat In Positive, Work in Positive
Question 8 Answer If you said Heat In Positive, Work Out Positive, you were right.
Question 9 Which of the following is NOT TRUE when analyzing the Boiler? Heat In is Positive Work Out is Positive Enthalpy In is smaller than Enthalpy Out There is no Work out of the Boiler
Question 9 Answer If you said work out is positive, you were right. There are no moving parts in a Boiler, so there is no way that work can leave the Boiler.
Heat from Burning Fuel
Saturation Saturation Temperature temperature at which boiling occurs Liquid contains all of the heat it can hold before changing into a gas At Saturation Conditions can have fluid as a liquid and a gas at the same temperature Saturated Liquid liquid at boiling temp. Saturated Vapor steam at boiling temp.
Saturation Temperature & Pressure Temp. 212 F 14.7 psia 70 F Heat Added
Saturation Temperature & Pressure 621 F 1800 psia Temp. 212 F 14.7 psia 126 F 2 psia 70 F Heat Added
Saturation Temperature & Pressure 621 F Saturation Curve 1800 psia Superheated Steam Temp. 212 F Saturated Liquid/Steam 14.7 psia Sub-Cooled Liquid 126 F 2 psia 70 F Heat Added
Supercritical Supercritical Boiler Curve Critical Point Superheated Steam 621 F 1800 psia Sub-Cooled Liquid Saturated Liquid/Steam Temp. Saturation Curve Heat Added
Question 10 Steam that has a temperature higher than saturation temperature for the pressure is called. Saturated Steam Superheated Steam Supercritical Steam Subcritical Steam
Question 10 Answer If you said superheated steam, you were right.
Question 11 For each saturation pressure there is a unique saturation. flow temperature state principle
Question 11 Answer If you said temperature, you were right.
Steam Tables List Parameters for Water under many conditions Can use to check performance of equipment Table 1 Saturation: Temperatures Table 2 Saturation: Pressures Table 3 Vapor
Table 1 Saturation: Temperatures
Using Table 1 At a temperature of 147 degf, Saturation pressure is 3.454 psia. Internal energy of Saturated Water is 114.95 Btu/lb Enthalpy of Saturated Steam is 1124.8 Btu/lb The heat necessary to make 1 lb of water into 1 lb of steam at 147 degf is 1009.9 Btu/lb (hfg)
Table 2 Saturation: Pressures
Table 3. Vapor
Mollier Diagram In back of Steam Tables Allows a quick ballpark check of parameters
Question 12 In the Steam Table below, saturation pressure for 149 degrees Fahrenheit is psia. 3.630 99.7 942.0 1.8704
Question 12 Answer If you said 3.630, you were right. It is listed in the column just to the right of the temperature column on the same line.
Question 13 In the Steam Table below, the enthalpy of steam at a pressure of 1100 psia and 600 degf is Btu/lb..4005 556.45 1171.8 1272.1
Question 12 Answer If you said 1272.1, you were right.
Plant Performance Heat Rate Input over Output Units BTUs per KW-hour
Factors Affecting Heat Rate Condenser Cooling Water Temperature Condenser Cleanliness Coal Fineness Coal Quality and Wetness Air Heater Operation Sootblower Usage Overall Plant Maintenance
Question 14 The units of Plant Heat Rate are. KW-hours per Btu Btus per KW-hour Btus per hour KW per Btu
Question 14 Answer If you said Btus per KW-hour, you were right. It is the ratio of what fuel was put in to the electricity that went to customers.