Evaporative Concentration of a Thermally Sensitive Chemical Chen - - PowerPoint PPT Presentation

Evaporative Concentration of a Thermally Sensitive Chemical

Chen 4450 Process Safety Auburn University November 27, 2006 Guest Speaker Robert D’Alessandro, P.E. Director of Process Engineering Degussa Corporation

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Introduction

Five Main Principles of Inherently Safer Chemical Plants:

Limitation of Effects

Use equipment fit for its service

Webster: Existing in something as an inseparable element. Synonyms: Innate, native, inbred, ingrained Substitution

Use safer chemicals

Simplification

Use less complexity

An Integral Part Of Attenuation or Moderation

Use the least hazardous conditions

Intensification or Minimization

Use less hazardous chemicals

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Lecture Objectives

Recognizing potential reactivity problems Safety aspects of connected equipment Safety instrumented systems Adiabatic calorimeters for obtaining proper data Gassy systems versus tempered systems Vapor-liquid disengagement in vessels Two-phase venting versus “all vapor” venting

Introduction to the following process safety related concepts:

Reactive System Pressure Relief Example Evaporative Concentration

• f a

Thermally Sensitive Chemical Integrating process safety into process design

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Process Flow Diagram - RA 2nd Stage Concentration

Steam 60 psig Z-100 Three Stage Steam Jet Vacuum System Chilled Water 5 C T 70 wt% RA From 1st Stage Concentration Steam 150 psig Process Offgas To Thermal Oxidizer 90 wt% RA To Crystalazer Chilled Water 5 C Process Condensate To Treatment Note 1: Barometric Leg Note 2: Equilization Line Note 3: 3 Barometric Legs P L L

RO

F T R-100 P-100 A-100 X-100 V-101 P-101 X-101 83 C 70 C 15 C 20 C

20 mmHgA

2,500 PPH 1,944 PPH Cond. 250 PPH 806 PPH

10 mmHgA 16.7 psia 16.7 psia

1 3 2 575,200 Btu/hr 308,800 Btu/hr 21.7 C 15.2 C

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Signs of Inherent Trouble

“70 wt% RA begins, at what the chemists describe as, a slow decomposition when temperatures exceed 120 °C.”

Be suspicious of “normal” laboratory data

“The chemists also noted some foaming when this slow decomposition occurred.”

Hints from Chemists or Operators

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Signs of Inherent Trouble

MSDS – Material Safety Data Sheet:

Excellent source of general safety information OSHA type data is good – hygiene, PPE, medical, fire fighting, etc. Physical property data is usually good “MSDS for 70 wt% RA also indicates this temperature limit.”

However, my experience indicates:

Reactivity data is lacking and sometimes wrong Better now then in the past, but still needs improvement Better for common petrochemicals then for specialty chemicals

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Signs of Inherent Trouble The hints from the chemists tell us that additional data is needed. What kind of data?

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Laboratory Scale Data

Consider:

A typical organic fluid at 80 °C in some container Surrounded by still air at 20 °C Factor 10,840 Bottom Line = Heat Loss Small Scale Has It Large Scale Doesn’t

?? WHY ??

Laboratory Heat Loss Equipment

Btu / Hour / Lb

Test Tube 10 ml Beaker 100 ml Cooling Rate

°C / Minute

0.09 0.06 542 341 Full Scale Heat Loss Equipment

Btu / Hour / Lb

Reactor 660 gallons Reactor 6600 gallons 0.048 0.004 4.6 0.05 Cooling Rate

°C / Minute

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E. Surface Area to Volume Ratio

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 0.001 0.010 0.100 1.000 10.000 100.000 1000.000

Volume (Gallons)

Surface Area / Volume (SF/Gallon)

L / D = 1 L / D = 4

3.8 ml 38 ml 380 ml 3800 ml

(S/V)Lab Scale >>> (S/V)Commercial Scale Heat Generation ~ Volume of Contents Heat Loss ~ Surface Area Small Scale Experiments Must Eliminate Heat Loss

Surface Area Volume Volume Ratio 10 ml 100 ml 1000 gallons 5000 gallons 124 57 2 1 10.5 4.9 0.145 0.085

Laboratory Scale Data

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Laboratory Scale Data

Two Forms of Heat Loss Both are magnified by large surface to volume ratios

Heat loss to the sample container caused by thermal capacity of test cell.

Capacity Carrying Heat Sample Capacity Carrying Heat System ≡ Φ

Phi Factor

t pf t f pb b t pf t f pb b t pf t f

C m C m C m C m C m + = + ≡ Φ 1

If Then

T UA Q Δ =

Heat loss to surroundings caused by temperature difference .

= ΔT = Q

Decrease Test Cell Mass Increase Sample Mass

Commercial Vessel Phi Factor = 1.05 to 1.10

Goal for Small Scale Equipment

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeters

ARC – Accelerating Rate Calorimeter

Invented by D.I. Townsend at Dow Chemical in the late 1970s Solved the ΔT problem But not the thermal inertia problem

Heavy Wall Test Cell Containment T Sample T Heating Elements Containment Vessel

Can not track very fast reactions Very sensitive at low reaction rates Still has important applications High Thermal Inertia Adiabatic Calorimeter Phi Factor: 2.0 ≤ Φ ≤ 4.0 Heavy wall test cell Built to withstand internal pressure

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeters

Low Thermal Inertia Adiabatic Calorimeters

Invented by DIERS in the early 1980s Solved the ΔT problem Solved the thermal inertia problem Can track very fast reactions Not sensitive at low reaction rates Phi Factor: 1.05 ≤ Φ ≤ 1.15 Thin wall test cell Pressure compensation prevents test cell rupture

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeters

Low Thermal Inertia Adiabatic Calorimeters Containment vessel isolation ball valve

Containment Vessel Pressure Transducer Test Cell Pressure Transducer “Super” Magnetic Stirrer Auxiliary Fill Line Rupture Disk (1900 psig) 3-Way Valve Filling Test Cell

• r

Pressure Equalization

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeters

Low Thermal Inertia Adiabatic Calorimeters

Thin Walled Low Thermal Inertia Test Cell Insulation for Maintaining Adiabatic Conditions A View of the Inside Pressure Containment

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

The type of data that is needed is now known! The experiment must now be specified. Evaporative Concentration

Data from a Low Thermal Inertia Adiabatic Calorimeters

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Tempered Versus Gassy Systems

Tempered Liquid Phase Systems:

T & P related directly to each other via the vapor pressure of components

In Open Systems:

Heat generation or addition causes vaporization of components Vaporization provides liquid phase cooling When vapor removal is sufficient, T (and P) stops increasing

In Closed Systems:

Essentially no vaporization occurs Pressure increases in step with increasing temperature

Examples of Tempered Systems:

Styrene polymerization Methanol vessel under fire Blowdown of a vessel containing liquid propane

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Tempered Versus Gassy Systems

Gassy Liquid Phase Systems:

Non-condensable gases are present or formed by reaction T & P are not simply related by the vapor pressure of the components

In Open Systems:

Heat generation or addition does not cause vaporization Cooling effects from vaporization do not occur Instead, the sensible heat content (temperature) of the liquid increases

Examples of Gassy Systems:

Decomposition of some organic peroxides Decomposition of some polymers Blow-down of a subcooled liquid containing dissolved gas

In Closed Systems:

Pressure increases almost without bounds Rossonic Acid Decomposition

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Experimental Specification

Testing 90 wt% RA in a Low Thermal Inertia Adiabatic Calorimeter:

Stainless Steel Open Test Cell Containment Backpressure = 300 psig Charge = 90 g (Fill ~ 75%) (Phi Factor ~ 1.1) Hold at 70 °C Test Normal Operating Condition Heat (4 °C Increments) and Search (5 minute holds) Until self-heating is observed Convert to adiabatic mode Allow test cell to self cool

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeter Data

Temperature Versus Time

50 75 100 125 150 175 200 225 250 2000 4000 6000 8000 10000 12000 14000

Time (seconds) Temperature (C)

Heat & Search Normal Operating Condition Self-Heating Detected ∆T ~ 120 °C Adiabatic Operation

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeter Data

Pressure Versus Time

250 275 300 325 350 375 400 425 2000 4000 6000 8000 10000 12000 14000

Time (seconds) Pressure (psia)

Containment Pressure Self-Heating Detected Pressure Rise ~ 90 psi Closed Test Cell ~ 12,000 psi

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeter Data

Self Heat Rate Versus Recipricol Temperature

0.01 0.10 1.00 10.00 100.00

• 3.0
• 2.9
• 2.8
• 2.7
• 2.6
• 2.5
• 2.4
• 2.3
• 2.2
• 2.1
• 2.0
• 1.9
• 1.8
• 1.7
• 1.6
• 1.5

Recipricol Temperature

Self Heat Rate (C/min) 110 C 94 C

Heat & Search Based on Lab Data Onset Temperature Maximum Self-Heat Rate 80 °C/minute Second Reaction Arrhenius Kinetics

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Adiabatic Calorimeter Data

Pressure Rise Rate Versus Recipricol Temperature

0.01 0.10 1.00 10.00 100.00 1000.00

• 2.6
• 2.5
• 2.4
• 2.3
• 2.2
• 2.1
• 2.0
• 1.9

Recipricol Temperature

Pressure Rise Rate (psi/min)

Maximum Pressure Rise Rate 180 psi/minute

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Now the proper data is known and available! So lets examine the Auburnite design concept Evaporative Concentration

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Process Flow Diagram - RA 2nd Stage Concentration

Steam 60 psig Z-100 Three Stage Steam Jet Vacuum System Chilled Water 5 C T 70 wt% RA From 1st Stage Concentration Steam 150 psig Process Offgas To Thermal Oxidizer 90 wt% RA To Crystalazer Chilled Water 5 C Process Condensate To Treatment Note 1: Barometric Leg Note 2: Equilization Line Note 3: 3 Barometric Legs P L L

RO

F T R-100 P-100 A-100 X-100 V-101 P-101 X-101 83 C 70 C 15 C 20 C

20 mmHgA

2,500 PPH 1,944 PPH Cond. 250 PPH 806 PPH

10 mmHgA 16.7 psia 16.7 psia

1 3 2 575,200 Btu/hr 308,800 Btu/hr 21.7 C 15.2 C

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Jacket Jacket

• r
• r

Total Working Tubes Tubes R-100 2nd Stage Concentrator Pressure Vessel 476 gallons 395 gallons 4'0" ID x 4'0" TT 30 psig & FV 100 psig & FV 316L Stainless Steel 316L Stainless Steel A-100 2nd Stage Concentrator Agitator Pitched Blade Turbine NA NA 2 - 18" Impellers 50 RPM x 5 HP NA NA 316L Stainless Steel NA X-100 2nd Stage Concentrator Overhead Shell & Tube Exchanger NA NA 630,000 Btu/hr 30 psig & FV 100 psig & FV Carbon Steel Carbon Steel P-100 2nd Stage Concentrator Bottoms Pump Centrufugal NA NA 10 GPM x 50' TDH 100 psig NA 316 Stainless Steel NA Z-100 2nd Stage Concentrator Vacuum System Steam Jets & Direct Contact Condensers NA NA 15 PPH @ 10 mmHgA 3 Stages 200 psig & FV NA Carbon Steel NA V-101 2nd Stage Concentrator Distillate Receiver Pressure Vessel 264 gallons 172 gallons 3'0" ID x 4'0" TT 15 psig & FV NA Carbon Steel NA X-101 2nd Stage Concentrator Distillate Receiver Shell & Tube Exchanger NA NA 340,000 Btu/hr 100 psig & FV 100 psig & FV Carbon Steel Carbon Steel P-101 2nd Stage Concentrator Distillate Receiver Centrifugal NA NA 60 GPM x 100' TDH 100 psig NA Ductile Iron NA Characteristics Shell Shell Volume Service Type Item Number Design Pressure Equipment List - 2nd Stage Concentration Materials of Construction

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Steam 60 psig T 70 wt% RA From 1st Stage Concentration 90 wt% RA To Crystalazer L

RO

F T R-100 P-100 A-100 83 C 70 C

20 mmHgA

2,500 PPH 1,944 PPH Cond. 70 C 556 PPH Water Vapor to Overhead Condenser

Saturated Steam @ 60 psig Temperature = 153 °C Onset Temperature = 94 °C This doesn’t look good! Inventory ~ 395 gallons Mass ~3,300 pounds Wetted Area ~ 62 ft2 Normal Operating T = 70 °C Onset Temperature = 94 °C Close, but OK

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Steam 60 psig T 70 wt% RA From 1st Stage Concentration 90 wt% RA To Crystalazer L

RO

F T R-100 P-100 A-100 83 C 70 C

20 mmHgA

2,500 PPH 1,944 PPH Cond. 70 C 556 PPH Water Vapor to Overhead Condenser

Quick Calculation

Perry’s Handbook For stainless steel, jacketed vessels with organics and condensing steam OHT Coefficient = 50 -150 Btu/h/sf/F

U ∆T T cond

Btu/h/sf/F °C °C 80 62 132 100 50 120 120 42 112

( )( )

UA Q T T UA Q ft A h Btu lb Btu h lb Q = Δ ⇒ Δ = = = =

2

2 . 62 / 000 , 559 / 1005 / 556

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Inventory Concerns:

Inventory is relatively large for such a potentially energetic material. Reducing inventory doesn’t work…………. Why?

Wall Temperature Concerns:

Inside wall temperature is probably higher than decomposition onset T No choice at the required capacity with the current configuration

Single Failure Upset Cases of Concern:

Loss of agitation Failed open steam valve Results in Increasing wall temperature Are there any others?

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

Multiple Sequential Failure Upset Cases of Concern:

Loss of cooling + stuck open steam valve Loss of vacuum + stuck open steam valve Failed closed pressure valve + stuck open steam valve And others!

CONCLUSIONS:

An uncontrolled exothermic decomposition appears plausible The concentrator relief device should be sized for this case Fortunately, the necessary data is available! But should sizing be based on “all vapor” venting or two-phase flow?

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Why Does Two-Phase Venting Occur

Results of Water Blowdown Experiments: Final Liquid Volume For “All Vapor” Venting 485 Gallons

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Why Does Two-Phase Venting Occur

Valve Opens Pressure Falls If Rate of Bubble Generation is High Enough Liquid Swells to the Top of the Vessel

Liquid Swell Caused by Volume Generation Not Liquid Entrainment Highly Dependent on Physical Characteristics of Components

Volumetric Generation Liquid Swell

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Rossonic Acid Decomposition Volumetric Generation of Non-Condensable Gas

Evaporative Concentration

“The chemists also noted some foaming when this slow decomposition

• ccurred.”

Remember this clue! Concentrator Fill ~ 83 % CONCLUSION: Design for Two-Phase Flow

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Larger Relief Devices Are Needed When Two-Phase Flow Occurs

Volume Balance Concept – Closed System

Gas Generating Exothermic Reaction T & P Increase

Wouldn’t It Be Nice

VOLUME GENERATION RATE VOLUME EXPANSION RATE

=

CONSTANT PRESSURE

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Larger Relief Devices Are Needed When Two-Phase Flow Occurs

Volume Balance Concept – Open System A More Realistic System

VOLUME GENERATION RATE VOLUME DISCHARGE RATE

=

CONSTANT PRESSURE

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Larger Relief Devices Are Needed When Two-Phase Flow Occurs

Volume Balance Concept – Open System

Definition of a Successful Emergency Relief Device: Provides a balance between volume generation and volume dissipation For the “Worst Credible” case conditions At a pressure no greater than the maximum allowable pressure

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Larger Relief Devices Are Needed When Two-Phase Flow Occurs

Volume Balance Concept Vg = Volume Generation Rate = Volume Discharge Rate = Vd ⎭ ⎬ ⎫ ⎩ ⎨ ⎧ = = = = ρ ρ ρ G A GA W V V

d g

Mass Flow Through Relief Device Two-Phase Density Two-Phase Mass Flux Relief Device X-Sectional Area

2 3 3 2

ft s ft ft lb ft s lb G = = ⎭ ⎬ ⎫ ⎩ ⎨ ⎧ ρ

Volumetric Flux =

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Larger Relief Devices Are Needed When Two-Phase Flow Occurs

Volume Balance Concept

Saturated Hexane at 320 °F & 132.8 psia

Two Phase Density

10 20 30 40 0.0 0.2 0.4 0.6 0.8 1.0 Inlet Void Fraction Two Phase Density (lb/cf)

Increasing Vapor Content Critical Mass Flux

500 600 700 800 900 0.0 0.2 0.4 0.6 0.8 1.0 Inlet Void Fraction Critical Mass Flux (lb/sf/s)

Increasing Vapor Content

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Larger Relief Devices Are Needed When Two-Phase Flow Occurs

50 100 150 200 250 300 350 400 450 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Inlet Void Fraction Volumetric Flux (cf/s/sf)

ALL LIQUID ALL VAPOR

⎭ ⎬ ⎫ ⎩ ⎨ ⎧ = = = = ρ ρ ρ G A GA W V V

d g

Volume Balance Concept

Saturated Hexane at 320 °F & 132.8 psia

Increasing Vapor Content

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Simple Ideal Vent Sizing Results

Inside Diameter = 4’0” T-T Length = 4’0” Total Volume = 475 gallons Fill Volumes = 428 gallons (90 %), 333 gallons (70 %), 238 gallons (50 %) Design Pressure (DP) = 50, 75, 100, 150 psig Maximum Pressure = (1.1) DP (10% accumulation) Maximum Pressure Rise Rate = 180 psi per minute

Consider the following cases:

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Simple Ideal Vent Sizing Results

Concentrator

475 Gallon Vessel 50 100 150 200 250 300 350 400 450 25 50 75 100 125 150 175

Design Pressure (Psig) Vent Area (Sq In) Fill Ratio = 90% Fill Ratio = 70% Fill Ratio = 50%

~ 12” Vent ~ 23” Vent

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

A large vent is required due to two-phase flow Can two-phase flow be avoided? Evaporative Concentration Yes By allowing enough room for vapor disengagement

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Vessel Disengagement

Bubbly Flow Regime Co = 1.2

0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00

0.1 1.0 10.0 100.0

Dimensionless Superficial Vapor Velocity Vessel Average Void Fraction Onset/Disengagement Boundary Vessel Condition Vapor Venting Region Two Phase Venting Region

Inside Diameter = 4’0” T-T Length = 4’0” Total Volume = 475 gallons DP = 50 psig & FV Disengagement Maximum Fill ~ 17 %

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Evaporative Concentration

With less inventory, how can the heat needed for the normal evaporation be added? Decrease the concentrator inventory Avoid two-phase flow Size the relief device for “all vapor” venting

Basis for New Concentrator Design Concept

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

New Concentrator Design

Inside Diameter = 4’0” T-T Length = 5’0” Total Volume = 535 gallons DP = 50 psig & FV DT = 500°F

70 wt% RA Emergency Water Water Vapor 90 wt% RA 20 mmHg 70°C LC On Upstream Vessel 5 psig Saturated Steam Tube Side Condensation Conditions 11.5 psia 93°C Pumping Trap Side View Top View Baffles

Working Volume = 70 gallons Maximum Volume = 100 gallons

Relief Device = 6” PSE based on vapor flow only

Minimization, Moderation, Limitation of Effects

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Is This Enough?

Shutdown Based On: Redundant High Level Redundant Process Temperature Redundant Tube Side Steam Pressure Quench water addition triggered by high process temperature only. Shutdown Feed & Steam

Safety Instrumented Systems (SIS) - Interlocks

Independent of the Basic Process Control System (BPCS)

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Concentrator – Top View

Emergency Vent Line Normal Vent Line Car Seal Open Full Port Block Valve Rupture Disk (hidden)

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Concentrator – Bottom View

Process Outlet Pipe Steam Condensate Line Stab-In Tube Bundle SIS Redundant Temperature Transmitters

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Concentrator – Bottom View

SIS Redundant Level Switches Process Outlet Pipe BPCS Level Transmitter

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

What Could Have Been Done Differently?

Conduct a high phi factor calorimeter test to better understand reaction mechanism. Conduct calorimeter tests to determine if the reaction system tempers at the maximum allowable working pressure of the vessel. Conduct a blowdown test to obtain a better feeling for disengagement dynamics. Use more sophisticated tools to analyze the possibility of utilizing smaller vent sizes.

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Alternate Schemes to Consider

Falling Film Evaporator

A very good alternative Usually have low heat transfer coefficients Probably more expensive then vessel/tube bundle combination

Agitated Thin Film Evaporator

Not the best for low viscosity liquids Considerably more expensive then vessel/tube bundle combination

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Connected Equipment

Jacket Jacket

• r
• r

Total Working Tubes Tubes R-100 2nd Stage Concentrator Pressure Vessel 476 gallons 395 gallons 4'0" ID x 4'0" TT 30 psig & FV 100 psig & FV 316L Stainless Steel 316L Stainless Steel A-100 2nd Stage Concentrator Agitator Pitched Blade Turbine NA NA 2 - 18" Impellers 50 RPM x 5 HP NA NA 316L Stainless Steel NA X-100 2nd Stage Concentrator Overhead Shell & Tube Exchanger NA NA 630,000 Btu/hr 30 psig & FV 100 psig & FV Carbon Steel Carbon Steel P-100 2nd Stage Concentrator Bottoms Pump Centrufugal NA NA 10 GPM x 50' TDH 100 psig NA 316 Stainless Steel NA Z-100 2nd Stage Concentrator Vacuum System Steam Jets & Direct Contact Condensers NA NA 15 PPH @ 10 mmHgA 3 Stages 200 psig & FV NA Carbon Steel NA V-101 2nd Stage Concentrator Distillate Receiver Pressure Vessel 264 gallons 172 gallons 3'0" ID x 4'0" TT 15 psig & FV NA Carbon Steel NA X-101 2nd Stage Concentrator Distillate Receiver Shell & Tube Exchanger NA NA 340,000 Btu/hr 100 psig & FV 100 psig & FV Carbon Steel Carbon Steel P-101 2nd Stage Concentrator Distillate Receiver Centrifugal NA NA 60 GPM x 100' TDH 100 psig NA Ductile Iron NA Characteristics Shell Shell Volume Service Type Item Number Design Pressure Equipment List - 2nd Stage Concentration Materials of Construction

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Summary

Critical information often comes from inconspicuous place. Keep your eyes and ears wide open!! Guessing is unacceptable In God we trust, everyone else bring the right data!! Avoid two-phase emergency venting where possible Its always easier to ride your bicycle down-hill Be weary of lab scale data when exothermic reactions are involved. Scale-up is usually not included in a chemistry curriculum!! A safety concept can not be realized without having the proper data Don’t go skydiving without reading the parachute instructions Chemistry knowledge is a key ingredient for process safety. Don’t sell your Morrison & Boyd on eBay!!

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Summary

What can happen, will happen. Remember Murphy’s Law. Keep the “stuff” in the pipes Once you start skidding, you are out of control. Integrate the safety concept and the process design Avoid problems by changing the basic process and/or equipment Pressure relief should be the last line of defense But not the only line of defense. Use the right equipment. Don’t try to fix your car without the right tools.

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Closing Remarks

Contact Information – Call or Write Anytime !!

Email: robert.dalessandro@degussa.com (best method) Phone: 251-443-2420 (I travel allot, so be patient) Address: Robert D’Alessandro Degussa Corporation 4301 Degussa Road Theodore, AL 36590-0606

I will be glad to help in anyway I can !!

Auburn University Chen 4450 Process Safety Robert D‘Alessandro, P.E.

Closing Remarks

Thank you !!

Auburn University Professor Chambers, Professor Eden, and Professor Roberts Degussa Corporation Professor Riemenschneider, Dr. Kemnade Students in Chen 4450