Introduction to Process Introduction to Process TechnologyTechnology

Unit 4Basic Physics

• What is Physics?• Why is Physics Important to Proc Oper?• Properties and Structure of Matter• Types of Energy• Temperature & Thermal Heat Transfer• Physics Laws• Flow Rates• Force and Pressure• Work and Mechanical Efficiencies• Electricity

Today’s AgendaToday’s Agenda

• Physics is the study of matter and energy

• Matter

• Energy

What is Physics?What is Physics?

Why Physics is Important to Proc Why Physics is Important to Proc Techs & Engineers & Other Techs & Engineers & Other

TechniciansTechnicians

• Explains the basic principles of the equipment they use on a day-to-day basis. Examples –

• Allows them to understand the processes used to convert raw products to end products

• Maintaining safe operations

Why Physics is Important to Proc Why Physics is Important to Proc TechsTechs

• Allows them to understand how to troubleshoot the process or to identify a problem and then solve the problem

• Allows them to understand how the process affects other processes downstream

• Solids• Liquids• Gases• Plasma

Matter and its StatesMatter and its States

Conservation of MatterConservation of Matter

• Matter cannot be created or destroyed; only changed

• Matter is considered to be indestructible

• Mass

• Weight

• Volume

Specific Properties of Specific Properties of Matter Matter

• Density

• Specific Gravity

Specific Properties of Specific Properties of Matter (Continued)Matter (Continued)

• Inertia• Force• Pressure• Buoyancy• Velocity

Specific Properties of Specific Properties of Matter (Continued)Matter (Continued)

Specific Properties of Specific Properties of Matter (Continued)Matter (Continued)

• Porosity• Elasticity• Friction• Viscosity• Hardness• Tenacity (tensile strength)

Specific Properties of Specific Properties of Matter (Continued)Matter (Continued)

• Ductility• Malleability• Conductivity• Adhesion• Surface Tension• Capillary Action• Temperature• Cohesive Force

• Atoms– Protons– Neutrons– Electrons

• Molecule

Structure of MatterStructure of Matter

• Atomic Number

• Atomic Weight

Structure of Matter Structure of Matter (Continued)(Continued)

States of EnergyStates of Energy

• Potential

• Kinetic

Temperature and State Temperature and State ChangesChanges

• Temperature• State Changes

– Evaporation– Boiling– Melting– Freezing– Condensing– Sublimation– Deposition

Temperature ScalesTemperature Scales

• Fahrenheit

• Celsius

• Absolute Zero– Kelvin = oC + 273– Rankine = oF + 460

Temperature (BTU) Temperature (BTU) TransferTransfer

• British Thermal Unit (BTU)

• Conduction

• Convection

• Radiation

Boiling PointBoiling Point

• The temperature of a liquid when its vapor pressure = the surrounding pressure

• Increasing the pressure of a system increases boiling point and vice versa… that is why water boils at a lower temperature up in the mountains compared to the coast

Vapor PressureVapor Pressure

• Vapor pressure– A measure of a liquid’s volatility and

tendency to form a vapor– A function of the physical and chemical

properties of the liquid– At a given temperature, a substance with

higher vapor pressure vaporizes more readily than a substance with a lower vapor pressure

Relationship of Boiling Relationship of Boiling Point/vapor pressure/ Point/vapor pressure/ surrounding pressuresurrounding pressure

• Liquids w/ High VP – Low BP• Liquids w/ Low VP – High BP• As surrounding Pressure

increases, then boiling point of liquid increases

Heat Rate EquationHeat Rate Equation

• Important for steam production, use

•Heat Rate = steam flow x specific heat capacity of steam x change in temperature

Thermal EfficiencyThermal Efficiency

• Applied to heat exchanger optimization

• Efficiency = (temperature in – temperature out)

temperature in

Physics LawsPhysics Laws

• Governing Gases – – Boyle’s Law– Charles’ Law– Gay-Lussac’s Law – Avogadro’s Law– Combined Gas Law– Ideal Gas Law– Dalton’s Law

• Governing Gases & Liquids - Bernoulli’s Law

NASA Video

NASA Video

General Gas LawGeneral Gas Law

• P1V1 = P2V2

n1 T1 n2 T2

Tanker Implodes http://www.break.com/index/tanker-implodes.html

Dalton’s Law of Partial Dalton’s Law of Partial PressuresPressures

Principles of Liquid Principles of Liquid PressurePressure

• Liquid pressure is directly proportional to density of liquid

• Liquid pressure is proportional to height (amount) of liquid

• Liquid pressure is exerted in a perpendicular direction on the walls of vessel

Principles of Liquid Principles of Liquid PressurePressure

• Liquid pressure is exerted equality in all directions

• Liquid pressure at the base of a tank in not affected by the size or shape of tank’

• Liquid pressure transmits applied force equally, without loss, inside an enclosed container

Flow RateFlow Rate

• Flowrate = Volume Time

Bernouli’s PrincipleBernouli’s Principle

• States that in a closed process with a constant flow rate:– Changes in fluid velocity (kinetic energy)

decrease or increase pressure– Kinetic-energy and pressure-energy changes

correspond to pipe-size changes– Pipe-diameter changes cause velocity

changes– Pressure-energy, kinetic-energy (or fluid

velocity), and pipe-diameter changes are related

Bernoulli PrincipleBernoulli Principle

Bernoulli’s PrincipleBernoulli’s Principle

Fluid FlowFluid Flow

• Laminar Flow

• Turbulent Flow

Laminar FlowLaminar Flow

Turbulent FlowTurbulent Flow

Turbulent flowTurbulent flow

Reynolds Number (R)Reynolds Number (R)

• Used to size pipe to ensure proper flow (either laminar or turbulent)

R = (Fluid Velocity)(Inside Diameter of Pipe)(Fluid Density)

Absolute Fluid Viscosity

Flow of SolidsFlow of Solids

• A variety of gases are used to transfer solids– Nitrogen (most common since inert),

air, chlorine, and hydrogen– In proper combination, these allow

solids to respond like fluids– Examples – plastics manufacture,

catalytic cracking units, vacuum systems

Measuring HeavinessMeasuring Heaviness

• Baume Gravity – standard used by industrial manufacturers to measure nonhydrocarbon heaviness

• API Gravity – measures heaviness of hydrocarbons

Force and PressureForce and Pressure

• Pressure = Force Area

Gauge MeasurementsGauge Measurements

• Absolute Pressure = atmospheric + Gauge

• Gauge pressure = anything above atmospheric– Gauge P = Absolute P – Atmospheric P

• Vacuum = a pressure below atmospheric

• Where atmospheric pressure = 14.7 psi = 760 mm Hg = 29.92 in Hg = 1 torr

WorkWork

• Work = Force x Distance

Mechanical AdvantageMechanical Advantage

• Mechanical Advantage = Resistance

Effort

or Work OutWork In

MA > 1 is good… so the larger the MA the better

Mechanical Advantage - Mechanical Advantage - MomentsMoments

• Inclined Plane and MALength of planeHeight of plane

Mechanical Advantage & Mechanical Advantage & EfficiencyEfficiency

Efficiency = Actual MA Ideal MA

Efficiency can never be > 1

ElectricityElectricity

• Electric current – • Electricity –• Direct Current –

– Example – battery

• Alternating Current –– Example – power generating station

ElectricityElectricity

• Ohm’s Law – relationship between current (A for amps), resistance (Ω for ohms), and electrical potential (voltage – v for volts)

• Voltage = Resistance x Current