Training - Level

7/27/2019 Training - Level

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Level 1 - Fundamental Training Level

Power Point Presentation Handouts

Level 1 - Level

1

Fundamental TrainingFundamental Training

Level 1

Level 1 - Level

2

Topics: Slide No:

• Why measure level? 3 - 5

• Level terminology 6 - 19

• Technology selection 20 - 29

• Technology (Pressure 30 - 55

Transmitter, HTG & Hybrid System

• Other Technology (Float, Capacitance, 56 - 75

Displacer, Servo, Nucleonic, Laser &

Ultrasound)

• Exercise 76 - 80

ContentsContents





Level 1 - Level

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Why measure level?Why measure level?5 Common Reasons5 Common Reasons

Inventory

• keep track of amount of material of material available for a process

Custody Transfer

• amount of material that is bought & sold in terms of volume or weight

Effieciency

• maximise storage tank capacity

• preventing unnecessary expense of purchasing additional vessels

Safety

• prevent spillage in open vessels

• prevent overpressure conditions in closed vessels that may result in

rupture

Consistent Supply• to maintain product quality in a process

» blending, pulp & paper

Level 1 - Level

4

Inventory

• Accuracy is primary dif ference

» better than 3 mm precision needed

• Appl ications need precise measurement because of $$$$$

» Transfer of ownership

» Exact quantity must be known

» Product cost

» Tend to be larger vessels

Process

• Appl ications are more concerned with:» Control of a product level within a range

» Safety (prevent overflow/ pump shutoff)

» Monitor inputs of components of a process

» Accuracy requirements vary widely

You can have amixture of process

and inventoryapplications in a

plant

Why measure level?Why measure level?

Inventory vs. ProcessInventory vs. Process





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Why measure level?Why measure level?Indication vs. ControlIndication vs. Control

Indication• on-site level check

• operator in terpret measurement

Indicators

– open loop control system

– help calibrate automatic control system

Control

• closed loop system

process ; point of measure ; transmitter

; controller ; control valve ; process

Level 1 - Level

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I/P LIC

LT

(Inflow)(Inflow)

• Level Loop Issues: – Control At Inflow or Outflow – Non-Self Regulating

Level terminologyLevel terminology

Level Control LoopLevel Control Loop





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I/PLIC

LT

(Outflow)(Outflow)

Level terminologyLevel terminologyLevel Control LoopLevel Control Loop

Level 1 - Level

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Interface

Level

VolumeMassDensity


ParametersParameters





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Level terminologyLevel terminologyParametersParameters

Liquid A to air/vapor interface

Liquid A

Liquid A to B interface

Liquid B

Interface• Interface measurement finds the boundarybetween two liqu ids stored in the same tank

» each liquid has different density

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Density

• Density is a measure of the mass per volume

Example:

– grams / cc

– pounds / cu ft

• Specific Gravity is a ratio of the density of afluid to the density of water, thus

density of fluid = SGdensity of water

Density of fluid = density of water * SG

Density



Mass = Density / Volume





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Volume

• Volume only correlates directly to level when:» Tank is an upright cylinder

» Density is constant

» Temperature is constant

» There is no change in tank wall position after filling

• Volume measurements are in units such as:

» gallons, liters, barrels...

• Level measurements are in units such as:

» inches, feet, millimeters, centimeters, meters...

• Correlation of volume to level varies with geometry of tank and may be expressed in terms such as:

» gal/inch, liters/meter, barrels/inch...

Volume


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Volume

• Vertical Cylindrical Tank

» v = πr 2l

• Horizontal Cylindrical

» v = πr 2atan[l½/(2r-l)½]+h(l-r)[l(2r-l)]½

• Sphere Tank

» v = πl2(3r-l)/3

r

h

l

r

hl

r

l





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Volume

• Horizontal Bullet Tank

» v = πr 2/3 * (3r-l) + 2r 2(h-2r) *atan[l½/(2r-l)½] + (h-r)[l(2r - l)]½

• Vertical Bullet Tank

» v = πr 2/3(3r-l) if l ≤ r

» v = πr 2/3(3r-l) if r < l < (h - r)

» v = πr 2(h-2r) + [π(l+2r-h)2]/3 * [3r-(l+2r-h)] if (h - r) ≤ l

h

l

r

h

l

r

Level 1 - Level

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Volume

• Tanks with Dished Ends

» no standard shape

– use strapping tables to determine volume

10

97

5

3

1

Point Level Volume(inches) (gallons)

1 0 02 5 103 10 32

4 15 685 20 1156 25 1737 30 2308 35 3139 40 39410 100 957

A look-up table thatrelates level to volumefor several discretepoints in a tank.

Commonly used toeliminate Bulging Error.

Bulging





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DensityChanges

Steam, vapors,

dust

Steam, vapors,

dust

0

PSIG-14.7

High

vacuum

High

vacuumViscous or

sticky fluids

Viscous or

sticky fluids

Temperature

extremes

Temperatureextremes Agitation Agitation

Abrasive

fluids

Abrasivefluids

Corrosive

processes

CorrosiveprocessesFoamFoam

...and the technologies may have to handle a number of ...and the technologies may have to handle a number of

application conditions.application conditions.

Level terminologyLevel terminologyMeasurement CharacteristicsMeasurement Characteristics

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Top-down

Bottom-up

Top-Down Measurement

• Poses less potential for leakage

• devices installed or removed

without emptying tank

e.g., dipstick, radar gauge

Bottom-Up Measurement

• Typically contacts the process

fluid

e.g., pressure transmitter,

weigh scale

Bottom-Up vs. Top-Down Measurement


Measurement CharacteristicsMeasurement Characteristics





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• An Inferred measurement is derived from another measurement

Ex: pressure transmitter

HeadPressure = Level , Mass = Level

Density Density

Stability of variables is critical to get a good inferredmeasurement.

If variables are not stable, compensation needs to bemade.

• A Direct measurement looks only at the desired variable

Ex: floats, dipstick


Inferred vs. Direct Measurement

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Continuous Measurement

• Constant detection of product height

• Concerned with amountof product

• May be used to cont rol

addition of other components to the vessel

Point measurement• Has the level reached

this point?

• High or low leveldetection

• Often used for alarmcontrol

• May start or stoppumps

• May open or closevalves

Continuous vs. Point Measurement


Measurement CharacteristicsMeasurement Characteristics





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NonNon--ContactContactimplies that thedevice does nottouch the fluid,but it could beinvasive

NonNon --intrusiveintrusive impliesthat the device maycome in contact with the

fluid, but does notprotrude into the fluid or interfere with fluidmovement

Intrusive

NonNon--invasiveinvasiveimplies that thedevice does notpass the walls of the tank nor touchthe processdirectly

Non-Contact vs. Non-Invasive vs. Non-Intrusive


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Hydrostatic

Radar Tuning ForkFloat

Capacitance

Dipstick

Sight glass

Gage Glass

Weight

DifferentialPressure

Ultrasonic Gap

Displacer

Nuclear

Ultrasonic

Bubbler

Technology selectionTechnology selection

Level Measurement TechnologiesLevel Measurement Technologies





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C o nt ac t in g N o n co n ta ct in g P o in t C o nt in u o us L iq u id s S ol id s

Bubb lersCapacitance

Conduct iv i ty

Displacers

Floats

HT G

Hydrostat ic

Laser

Magnetostr ic t ive

Nucleonic

Opt ical

Phase Dif ference

Radar

Resistance T ape

Rotat ion Suppress ion

Servo

Tape LevelThermal

Ultrasonic

Vibrat ion

Weighing

Technology selectionTechnology selectionClassification of Level Measurement TechnologiesClassification of Level Measurement Technologies

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D en s it y In te rfa ce L ev el Mas s

Bubblers

Capacitance

Displacers

Floats

HT G

Hydrostatic

Laser

Magnetostr ic t ive

Nucleonic

Phase Differenc e

Radar Resistanc e Tape

Servo

Tape Level

Ultrasonic

Weighing

Note: Onlycontinuousdevicesincluded


Classification of Level Measurement TechnologiesClassification of Level Measurement Technologies





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• Why is the level measurement needed?

What are you try to measure?What are you trying to achieve?

– Indication of fluid level

– Alarm set point to prevent spil l over

– Transfer (Sale) of product

– Contol of Product Mix

– Leak Detection

– Interface detection

• What are the condit ions wi thin or on the vessel? Product turbulence

Obstructions

Mounting constraints Angle of repose for sol ids

Temperature and pressure limits

Technology selectionTechnology selectionFactors To Consider Factors To Consider

Level 1 - Level

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Factors To Consider Factors To Consider • What are the environmental condi tions?

Ambient Temperature

Humidity

Vibration

Electro Magnetic Interference(EMI)

Transient protection

• What are the product characterist ics?

Corrosive

Viscous

Dusty, Foam Variable Densit y

Variable Dielectric constant

Tendency to Coat

Interfaces, gradients, suspended solids

Steam or other vapors





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Common Density/ Temperature Changes


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Typical Dielectric/ Temperature Changes


Factors To Consider Factors To Consider





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• What are the instrument requirements? Performance requirements

Location approvals

Power requirements

Output requirements

Number, location, and size of taps

Total costs

– Product

– Installation

– Maintenance

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EnvironmentalFactors

ProcessConditionsDevice


Performance ConsiderationPerformance Consideration

Direct vs inferred

Measurement capabilities

Rangeability

Temp changes

Vibration

Noise

Density changes

temperature changes

static pressure

agitation

aeration

foam

dielectric changes





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Approximate values are shown. Pressure and temperature limits are shown independently of each other.Temperature, oF

-240 32 195 600 800-40-100 320 400 900+

P r e s s u r e ,

P S I

atm

10000+

73

1000

3626

Displacer

Nucleonic

Ultrasonic

Ultrasonic Point

Pressure/HTG

Radar

Capacitance

Pressure w/ seals

Technology selectionTechnology selectionWorking Capabilities Vary with TechnologiesWorking Capabilities Vary with Technologies

Level 1 - Level

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In open vessel a pressure transmitter

mounted near the bottom of the tank

will measure the pressure

corresponding to the height of the

fluid above it.

Open Vessel Level Measurement

XMTR

HL

Patm

Phead

Patm

What happen to

Atmospheric pressure? Cancelled Off

Phigh - Plow = Phead

Plow = Patm

Phigh = Phead + Patm

TechnologiesTechnologies

Pressure TransmittersPressure Transmitters





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What happens when the liquid level drop below thesensor ?

Transmit ter mounted above the tap in an open vessel

XMTR

HL0%

100%

0% h

g

The 0% has to be at least at the same level as the transmitter

sensor or below the tapping poin t..

The sensor will not be able to sense any pressure change !!

TechnologiesTechnologiesPressure TransmittersPressure Transmitters

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“ Zero Suppression” is often applied to compress the range of the

transmitter OR to cancel the effects of the liquid head in the pipe

connecting the transmitter to a tank when the transmitter is mounted

below the vessel connection.

XMTR

HL

Actual ZeroSuppressed

4mA

20mA Max. Level

Min. Level R a n g e

XMTR

HL

Actual Zero

Suppressed4mA

20mA Max. Level

Min. Level

R a n g e

At min. level the High side pressure is high than the low side pressure







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“ Zero Elevation” is often applied to cancel the effects of the head

caused by the seal fluid in the reference leg (low side) of a transmitter measuring level in a pressurized vessel.

XMTR

Actual Zero

Elevated

4mA

20mA Max. Level

Min. Level R a n g e

L H At min. level the low side pressure is high than the high side pressure


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Dry leg: no fluid in low side impulse

piping, or leg

If the gas above the fluid does not

condense, the piping for the low

side of the transmitter will remain

empty.

Closed Tank Level Measurement (Dry Leg)

XMTR

HL

Phigh = Ptop+Phead

Plow = Ptop

Ullage or

Vapor

Phead

Phigh - Plow = Phead







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Wet leg pressure is additive to

pressure on low side of the transmitter.

If the gas above the liquid condenses,

the piping for the low side of

transmitter will slowly fill with liquid. To

eliminate this potential error, the pipe

is filled with a convenient reference

liquid.

Closed Tank Level Measurement (Wet Leg)

XMTRHL

Phead

Ptop= Ullage

Phigh =Phead+Ptop

Phigh - Plow = Phead - Pwet leg

Pwet

Plow=Pwet leg+Ptop


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• Bottom-mount technology: potential leakage

• Often requires 2 taps

• Variable density creates errors

• Temperatures beyond 600 F

• High vacuum applications are tricky

• Highly corrosive processes limit life

• Abras ive processes can damage d iaphragms

• Liquids Only

Limitations







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Consists of air supply, pressure regulator,flow meter, transmitter & extended tube.

Can be used for very corrosive

applications.

Tank vented.

Air is bubbled through the tube at a

constant flow rate. The pressure required

to maintain flow is determined by the

vertical height of the liquid above the tube

opening times the specific gravity.

Pin(flow=const)

Bubbler System

Pressure to maintain flow = Phead

S.Gf

H

Phead = H * S.Gf

TXR


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Gauge Pressure Transmitter

Air

Supply

Valve

• Allows dp to be a top

down measurement

• No process contact with

transmitter

• Open or low pressure

• Control of Air supply is

important for accuracy

Appl ication of Bubbler system:







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Reliable, Simple, Easy to Use, WellUnderstood, Flexible Uses:

DifferentialPressure

Transmitter

Diaphragm Seals extend l imitations

due to process conditions such as:

high temperatures

corrosion

viscous materials

suspended solids

plugging

sanitary needs


Remote Seals

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•CPI / HPI

Batch reactors

digesters

fractionators

distillation column

bottoms and reflux drums

separators

surge drums

reservoirs intermediate storage...

•Power

drum level

dearators...

•Pulp & Paper

Headbox

Stock Tanks

Chemical Storage tanks

Evaporators

Low concentration

liquor tanks...

•Food and Beverage

Fermentorsstorage tanks

aging tanks

brew kettles...

And many more!

Typical Pressure Applications







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Wavelength, Meters

10 -11

10 7

10 5

10 3

10 1

10 -5

10 -3

10 -1

10 -9

10 -7

10 -13

10 2

10 18

10 16

10 14

10 12

10 10

10 8

10 6

10 4

10 20

10 22

FrequencyCycles/second

gamma rays

x-rays

ultra violet

visible light

------ultra high freq----------

----------TV broadcasting------------------FM Radio-------------

-------low frequency------------

Radar,

3-30 GHz

Microwave oven,

2 - 10 GHz

Cellular, pager,300-3000 MHz

Electromagnetic

Spectrum Radar is anElectromagnetic Wave

Radio Detection And Ranging

--------super high freq---------

TechnologiesTechnologiesRadar GaugeRadar Gauge

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• Pulse

» Measures range ( distance )

» Transmits a pulse and measure time until

echo is received

» Accuracy depends on ability to measure time

– Radar signals travel at the speed of light.

– Must measure in picoseconds ( x10-12 ) !

– Cost-effective electronics do not exist to do th isaccurately !

Radar Techniques


Radar GaugeRadar Gauge





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• FMCW: Frequency Modulated Continuous Wave» Does NOT calculate time-of-flight

» Evaluates the phase difference between the

transmitted and return signal

» Plotting these phase differences against the

transmitted signal yields a result proportional to

distance

Radar Techniques


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• Non Contact, Non Intrusive

• Tolerates Wide Range of Process Condit ions

» Corrosive Processes

» High Temperatures

» Changes in Vapor Space

» Variable Density

» Variable Dielectric

» Viscous or Sticky Products• Low Maintenance

• No Special Licenses Required

• Can measure long distances

• Liquids, pastes, solids


Radar GaugeRadar Gauge Advantages of Radar Gauge





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• Sensors can be completely removed from process by

use of a window made out of a nonmetallic material,

such as Teflon, Ryton, Ceramic

• Sensors can be removed from the process without

opening the vessel

Radar Application Considerations

• Cost

• May not work with processes with low dielectric constant

• May not work in applications with large amounts of

turbulence

• Process connections tend to be large (>4” flanges)

Radar Limitations


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•Pulp & Paper

»High Density Storage

»Color tanks

»Bleach tanks

»Hydropulpers

»Retention tanks

»Black liquor tanks

•Pharmaceutical

»Batch reactor »Chemical s torage

•Power

»Slurries

•Chemical

»Polymers

»Latex

»High temp

»LPG tanks

»Butane sphere

»Batch reactors

»Two-phase sludge

»Cyclohexane

•Minerals

»Steel Scale Holding Tanks

And More!

Possible Applications







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Both technologies

Top down, non contact

Easy to install

Good for abrasive materials, slurries

Not affected by changing fluid properties: density, conductivity, dielectric

Radar vs. Ultrasonic Gauge

Differences:Radar

Full vacuum to several hundred psi

Wide temperature limits

Can handle steam, fog, vapors

Can handle some foams and

agitation

Can be used with windows

Ultrasonic

Very slight vacuum to about 100

psi

Narrow temp band (<200 F)

Is greatly affected by changes invapor space

Signal is lost in foam and

agitation


Similarities:

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Gas Temp (oC) RADAR ULTRASOUNDmillion m/s m/s

Dry Air 0 299.91 331.8

100 299.94 386

Water vapor 100 299.10 404.8

Carbon Dioxide 0 299.85 250.0

50 299.87 279.0

Ammonia 0 299.93 415.0

Acetone 0 297.64 223.0

Source: Instrument Engineer’s Handbook, Liptak

Radar vs. Ultrasonic Gauge







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Tank

I s o l a t i n g

V a l v e

Float

DrainValves

Indicator

Indicator

External Still pipeto guide the float

Float

Internal Still pipeto guide the float

Float-operated gauge level-indicator, indicates liquid level in cone or flat

roof unpressurised tanks.Recommended for use on tanks storing water, fuel, oil, chemicals or other

liquid products where operations do not require extreme accuracy.

TechnologiesTechnologiesFloat MechanismFloat Mechanism

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C = KE oAd

w h e r e

K = d i e le c t r i c co n s t a n t o f m a t e r i a l

Eo = p e rm i t i v i t y o f v ac uu m

A = A r e a o f p la t e s ( p r o b e )

C = c a p a c it a n c e ( p F )

d = d i s t a n c e b et w e e n p la t e s

d

k

• A capacitance instrument measures amount of capacitance between two plates of a capacitor.

• The capacitance of a capacitor increases if a dielectric isplaced between the plates

• Circuit applies high frequency signal to probe

Other technologiesOther technologies

Capacitance ProbeCapacitance Probe





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Nonconductive Fluid

d

Conductive Fluid

Nonconductive

Coating

• Process fluid is the dielectricbarrier

• Tank Wall forms second plate

• The variation of dielectric is themeasurement

• Process fluid is the second plate

• Insulation on probe is dielectric

• The variation of the plate size isthe measurement

How Capacitance

varies with process

fluid?

Level isproportionalto dielectricchange

Level isproportionalto plate areachange

Other technologiesOther technologiesCapacitance ProbeCapacitance Probe

Level 1 - Level

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• Limitation

– Change in Dielectric creates error

– Coating on probe by product creates errors

– With non metallic tanks or tanks withoutvertical walls, addition of reference probe

is required

– Calibration can be difficult especially since onecannot “ bench calibrate”

– Changing vapor space can affect output


Capacitance ProbeCapacitance Probe





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•Pulp & Paper

Sewage level

Liquor tanks

Bulk solids

•Chemical

Interface: fatty

acid/water, oil/water

Carbon black

Separators

•Food & Beverage

Storage silos

•Oil & Gas

Water bottom

Water cut

Potential Applications

Other technologiesOther technologiesCapacitance ProbeCapacitance Probe

Level 1 - Level

54

Angular movement is then

converted to electrical or

pneumatic output.

pounds

0

pounds

0Based on Buoyance Force

The displacer is buoyed up by a

force proportional to the weight of

the liquid it displaces

Vertical movement of the

displacer is converted to angular

movement by mechanical

linkages

Buoyant forceincreases as level rise


DisplacersDisplacers





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Liquid LevelMeasurement InterfaceMeasurement DensityMeasurement

Good for short span measurement

Other technologiesOther technologiesDisplacersDisplacers

Level 1 - Level

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Benefits:

• Simple, Reliable.

• Good for Interface measurements.

• Good for Density measurements.

• Unaffected by Agitation.

• Tolerates High Temperatures and pressures.

• Point or Continuous .

Limitations:

– Does not tolerate viscous, dirty, or sticky fluids – Variable density causes errors in level measurement

– Typically used for smaller spans (cost effective)

– Must be installed carefully

– Intrusive & Contact


DisplacersDisplacers





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• Typical Applications:Oil and Water interface

Oil and Gas Separators

Stripper Reflux Drum Level

Dehydration Units

Effluent Separators

Absorpt ion Towers

Condensate Discharge Accumulators

Densi ty and Interface Measurements

Other technologiesOther technologiesDisplacersDisplacers

Level 1 - Level

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Uses a combination of a displacer and a

spring balance

The servo motor strives to obtain an

equilibrium between the displacer and

the balance. Any change in level will

cause a change in equilibrium.

Advantages:

– Very precise (1 mm accuracy)

– Can measure level, interface

– relatively low cost

Limitations: – Intrusive

– Mechanical linkages

Cable

Storage Drum

BalanceDetector

Servo

Motor

Displacer


Servo GaugingServo Gauging





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Gamma rays are emitted from the

source. The presence or absence of the

gamma rays is measured by the

detector .

Nucleonic level switches use

radioisotope sources sized to provide

measurable radiation at the detector

when no product material is present

between source and detector.

DetectorGamma

Source

Single Point System

Other technologiesOther technologiesNucleonic GaugingNucleonic Gauging

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Nucleonic level transmitters use the

same radioisotope sources, but

respond to the total absorption of gamma rays as they pass from the

source to detector.

The amount of radiation reaching

the detector is inverselyproportional to the amount of

material in the vessel.

Detector

Source

Continuous System


Nucleonic GaugingNucleonic Gauging





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– Unaffected by:

• High temperatures

• High Pressures

• Corrosive Materials

• Abrasive Materials

• Viscous Materials

• Agitation

• Clogging/Plugging

– Point and Continuous

– Liquids and Solids

– Interface (based on H2

density)

Advantages:

– Large density changes

can create errors

– Layer of coating on vessel

walls create errors

– Licensing Required

– Leak Checks required

– Cost

Limitations:

Other technologiesOther technologiesNucleonic GaugingNucleonic Gauging

Level 1 - Level

62

•Chemical

Distillation Tower

Batch Reactor

Storage Tanks

Resin Bed level

Hydrocracker reactor

•Pulp & Paper

Digester Level

Wood Chip Bins

Bleach Tower

Consistency

Effluent Waste

Slurries

Liquor concentrates

•Refining

Fractionator Tower

Surge Tanks

Coke Drum Interface

Desalter


Hopper Level

Blending Vats

•Mining

Crusher Level

Storage silos

Slurries

•Utilities

SO2 / Lime scrubber

Fly ash Slurries


Nucleonic GaugingNucleonic GaugingTypical Applications





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63

glass window

laser

device• Function: Uses infrared light to send a

focused beam towards surface. Time of

travel and reflection is measured.

• Narrow, focused beam: good for

applications with space restrictions.

• Non contacting: uses a window

• Accuracy: +/- 1 cm

• Works best in cloudy, shiny liquids or

solids

• May pass through surfaces of clear, still

fluids

• Cannot tolerate dust, fog, steam or vapors

• High cost

• Alignment is critical

Other technologiesOther technologiesLaser Laser

Level 1 - Level

64

• Advantages:

Non Contact

No element contamination

Can be used for liquids and solids

Tolerates Many ProcessConditions:

Sound Waves

A sound pulse(9 to 160 kHz) is transmitted and reflects off the surface

back to the transceiver. The true reflected echo pulse is extracted and

the time interval between transmission and reception is evaluated

electronically.

The higher the level the faster echo reflected

9 Varying Density

9 Corrosive Processes

9 Viscous Product

9 Varying Dielectric

9 Sludge Buildup


Ultrasonic GaugingUltrasonic Gauging





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• Conditions of the vapor space impact

speed of signal travel and thus, the

measurement

• Changes could be due to:

– temperature

– dust

– vapor composition

– stratification of the vapor

• Some units have temperature

compensation

• Gas blankets can be used to provide

uniform vapor space condition

Sound Waves

Appl ication Considerations

Other technologiesOther technologiesUltrasonic GaugingUltrasonic Gauging

Level 1 - Level

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• Process surface conditions can

affect signal return . Surface must

have ability to reflect signal.

• Heavy agitation and foam may

cause signal to be absorbed

• Vortex in fluid can misdirect signal

• In open, outdoor installations, wind

can blow signal off coarse• Stilling wells can be used to isolate

the surface and contain signal.

Appl ication Considerations


Ultrasonic GaugingUltrasonic Gauging





Level 1 - Level

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Limitations – not suitable for vacuum service

– Cannot to lerate high temperatures (>200 F)

– Foam in terferes with signal

– Agitation may distor t s ignal

– Internal obstacles can create false echoes

– Nearby equipment could generate frequencies thatwill cause errors

– Vapor pressure limited to 50 psi

Other technologiesOther technologiesUltrasonic GaugingUltrasonic Gauging

Level 1 - Level

68

•Chemical

Distillation chamber

Corrosives

Slurries

Latex PVC

Waxes


Dearating vessel

alcohol fermenter

baking batter

chocolate

dairy products

grain storage

•Cryogenic systems (point level)

•Waste water

Clarifier

Settling tanks

Reservoirs

Flood control

Sludge levels

•Pulp & Paper

Black liquor w/ solids

•Pharmaceutical

Emulsions

Lotions

•Marine

Fuel or ballast water indication

Bilge alarm


Ultrasonic GaugingUltrasonic GaugingTypical Applications





Level 1 - Level

69

1. Which has the best accuracy on 6 meter High Water tank?

A. Hollow or glass fill float with mechanical gauge (1 inch)B. “Servo” Gauge (1 mm)

C. Pressure Transmitter ±0.1% of F.S [ ]

2. An inground reservoir is 5 meters deep. Which of the following

method(s) will be suitable to measure and transmit the level without

having to dig a hole to reach the bottom of the reservoir or the scour

main. (Answer Yes [Y] or No [N])

A. Differential Pressure [ ]

B. Servo Level Gauge [ ]

C. Capacitive Probe [ ]

D. Nucleonic Gauging [ ]

E. Ultrasonic Gauging [ ]F. Radar Gauging [ ]

G. Bubbler System [ ]

ExerciseExercise

Level 1 - Level

70ExerciseExercise

3. For HTG, why is a 2nd Pressure Transmitter added to tank in the

middle ?

4. Which one of the following tank gauging system is based on Mass?(A) Radar (B) Nucleonic(C) Servo Balance(D) HTG [ ]

5. Which of the following statement about Radar Gauge is NOT True ?(A) Top-down mounting

(B) Can handle agitated & sticky process fluid

(C) Can be used on a tank with non-metallic internal surface.

(D) Can handle process with deep vacuum [ ]





Level 1 - Level

71

10’

5’ Assuming SG is = 1.1

What is the volume?____________ft3

What is the density of this fluid?___________#/ft3

What is the mass?__________pounds

What is the pressure level reading? ________in H2O

water = 62.4 # / ft3

ExerciseExercise

6.

Level 1 - Level

72

10’

5’

Now, suppose the SG changes to 1.05 and the

level does not change

What is the volume?____________ft3

What is the density of this fluid?___________#/ft3

What is the mass?__________pounds

What is the pressure level reading? _______in H2O

water = 62.4 # / ft3

ExerciseExercise

7.




Level 1 - Level

73ExerciseExercise

Pmeasured = 150 inH2O

s.g. = 1.5

Pin(flow=const)

What is the fluid level in the tank?

8.

Documents

Training - Level