INDUSTRIAL RESOURCES, INC Power Plant 2009 - Industrial Resources, Inc. Power Plant Fundamentals...

transcript

Power Plant Fundamentals Training

Module 2 Power Plant Theory

INDUSTRIAL RESOURCES, INC

Power Plant Fundamentals Training

Industrial Resources, Inc. A Training Services Company

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.

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

Molecules in fixed positions Example: Ice is solid form of water If Temperature increases enough, melts

Liquid

Molecules not in fixed positions, but close Takes shape of container Example: Ice is solid form of water

As add Heat, Liquid expands.

Add enough Heat, Liquid starts to turn to 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 CO2

Liquid CO2 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

Barometer

Maintaining a Vacuum is Difficult, So We Don’t

AbsolutePressure

Absolute 0 Pressure

Absolute Pressure

psia bar

14.7 psia

Gauge Pressure

Absolute 0 Pressure

Absolute Pressure Gauge Pressure

psia bar

psig barg

14.7 psia 0 psig

34.7 psia 20 psig

Vacuum Scale

Absolute 0 Pressure

Absolute Pressure Gauge Pressure

Vacuum

psia bar

psig barg

Back-Pressure

In. Hg vac

In. Hg abs.

14.7 psia 0 psig

34.7 psia 20 psig

2 in. Hg is 1 psi

Fluid Pressure

Units are Gauge Pressure units Some gauges have more than 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

Enthalpy

Formula for 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

Temperature Scales

Boiling Temperature

Freezing Temperature

Fahrenheit (degF) Celsius (degC)

212 degF

32 degF 0 degC

180 degF 100 degC

9 degF = 5 degC

100 degC

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

Equipment Enthalpy

Potential Energy

Kinetic Energy

Potential Energy

Enthalpy

Kinetic Energy

Heat In Positive

Work Out Positive

Need Moving Parts for Work to occur

General Energy Equation

Equipment Enthalpy

Potential Energy

Kinetic Energy

Potential Energy

Enthalpy

Kinetic Energy

Both small amounts, so can ignore them

Kinetic Energy – energy due to Speed

Potential Energy – energy due to position

General Energy Equation - Boiler

Boiler Enthalpy Enthalpy

General Energy Equation - Turbine

Turbine Enthalpy Enthalpy

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

Heat Added

212 F 14.7 psia

Heat Added

212 F 14.7 psia

126 F 2 psia

621 F 1800 psia

Heat Added

212 F 14.7 psia

126 F 2 psia

621 F 1800 psia

Sub-Cooled Liquid

Saturated Liquid/Steam

Superheated Steam

Saturation Curve

Supercritical

Heat Added

621 F 1800 psia

Sub-Cooled Liquid Saturated Liquid/Steam

Superheated Steam

Saturation Curve

Critical Point Supercritical Boiler Curve

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 “ball-park” 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.

INDUSTRIAL RESOURCES, INC Power Plant 2009 - Industrial Resources, Inc. Power Plant Fundamentals...

Documents