Problem Statement Analysis of Chemical Heat Pump Analysis of Cooling Tower Analysis of Boiler.

Problem Statement

Analysis of Chemical Heat Pump

Analysis of Cooling Tower

Analysis of Boiler

Flash tank

Heat exchangerExothermicreactor

Distillation column

endo reactor

Flash tankH2Acetone2-Propanol

H2

condenser

MIXED

Acetone

H2

Acetone2-prop

Compressor 1

Pump 1

Compressor 2

Liquid

gas

Reduction valve

water

Hot airCool air

Pump 2

Air 79 % N2 21 % O2

Natural gas

Combustion gassesCO2, H2O, N2, O2T= 375 F

BFW

SS

CR

BOILER

reboiler

Cooling tower

Ambient air85 F80 % RH

CWR 103 F

Exit air

Pump 3

CWS 75 F

COOLING TOWER

MOCSWORKING DIAGRAMPBL-7-98

WATER

2- prop & acetone

Given: Chemical Heat Pump

Diameter of L1 = 6.35 mm

Average Velocity = 10 m/sec

Temperature L6 = 200 C

Mole composition of L1= .97 2-Propanol

Mole composition of L5= .02 2-Propanol

Given: Chemical Heat Pump (continued)

Hot Air going into Endo 23.8 C

Relative Humidity 80 %

Cool Air coming out of Endo 15.5 C

Required: Chemical Heat Pump

Energy Supplied into Endo Reactor (Qin)

Diameter of L6

Partial Pressures of L6

Amount of Water Condensed in Endo

Endo Reactor

Q in

Hot air

Nextpage

L 202

L 2

L 201

Acetone2- Prop

L 3Condenser

L 5

L 4

L 803

Water

Cool air

L 303

Pump 2

L 1L 101

H2

Re-boiler

Reduction valve

Acetone2-Prop

L 801

CWR

Flash Tank 1

DistillationColumn

Analysis: Chemical Heat Pump (Endo)

Qin = 353000 Btu/ hr (29 ton unit)

Water Condensed 168 lb/hr (21 gal/hr)

Exothermic Reactor

L 202 L 203Compressor 1

L 5Pump 1

ExoReactor

L 6L 501 Acetone

Heat ExchangerL 7

L 802

L 801

Gas

Compressor 2

L 8

L 804

H2

H2

Acetone2-Propanol

Flash Tank 2

H2

Analysis: Exothermic Reactor

Diameter of L6 = 29.0 mm

Partial Pressure: 1.96 ATM Acetone

0.04 ATM 2-Propanol

Given: Cooling Tower

Cold Water Return 39.4 C

Cold Water Supply 23.8 C

Input Ambient Air 29.4 C

Relative Humidity 80 % (Ambient Air)

Exit Air 30.5 C RH 90 %

Given: Cooling Tower (continued)

Diameter for CWS and CWR: 0.05 m

Cooling Tower

CWR103 FCooling

Tower

Ambient Air85 F80 % RH

L 301

L 302

Exit Air

Pump 3

WaterL 303CWS 75 F

Required: Cooling Tower

Velocity for Cold Water Supply

Velocity for Cold Water Return

Pounds of Dry Air from Cooling Tower

Analysis: Cooling Tower

Velocity of Cold Water Supply: 1418.0 m/hr

Velocity of Cold Water Return: 1425.0 m/hr

Pounds of Dry Air: 34,600 lb dry air/ hr

Given: Boiler

Steam Supply 220 psig (q=1)

Cold Return (q=0)

Temperature of Exit Gas 190.5 C

Combustion Gasses: CO2, H2O, N2, O2

Excess Air 40 %

Given: Boiler (continued)

Diameter for SS and CR: .05 m

Boiler

Boiler Feed WaterBoiler

CombustionGassesCO2,H20,N2,O2

L 901L 903

CR

SS

Natural GasAir79 % N221 % O2

T= 375F

L 902

Required: Boiler

Velocity of Steam Supply

Velocity of Cold Return

Flow Rate of Natural Gas

Percent Composition of Exit Gasses

Analysis: Boiler

Velocity Steam Supply: 3960.0 m/hr

Velocity Cold Return: 36.7 m/hr

Amount of Natural Gas: 3.51 tons/month

Analysis: Boiler (continued)

Composition of Flue Gasses:

CO2 = 7.0 %

H20 = 13.9 %

O2 = 5.6 %

N2 = 73.5 %

Differential (Batch) Distillation

Bryan Gipson

John Usher

November 12, 1997

121110987

654321

Feed Pump

Cooler

Distillate

CoolingWater

CoolingWater

Reboiler

Reboiler Pump

Bottoms

CalrodHeater

Condenser

Heater

Feed

ElectromagneticReflux Control

Cooler

Progress

• Familiarization with System

• 2 Runs Conducted– First Run Inconsistent– Second Run Okay

• Data Taken– Initial Volume: 14 liters– Time vs. Temperature– Rate of Distillation

Differential Distillation

71

71.5

72

72.5

73

73.5

74

74.5

75

0 5 10 15 20 25 30 35t, min

T, d

eg

C

Observed

Theoretical

Observations

• Temperature Change– Less than Predicted

• Rate of Distillation– Observed: Sporadic, ~94 ml/min– Theoretical: Decreasing, 215-200 ml/min

Next Steps

• Resolve Inconsistencies

• Conduct More Data Runs

• Estimate Heat Losses

• Compare Column Performance to Predictions

Differential (Batch) Distillation

Bryan Gipson

John Usher

November 12, 1997

121110987

654321

Feed Pump

Cooler

Distillate

CoolingWater

CoolingWater

Reboiler

Reboiler Pump

Bottoms

CalrodHeater

Condenser

Heater

Feed

ElectromagneticReflux Control

Cooler

Progress

• Familiarization with System

• 2 Runs Conducted– First Run Inconsistent– Second Run Okay

• Data Taken– Initial Volume: 14 liters– Time vs. Temperature– Rate of Distillation

Differential Distillation

71

71.5

72

72.5

73

73.5

74

74.5

75

0 5 10 15 20 25 30 35t, min

T, d

eg

C

Observed

Theoretical

Observations

• Temperature Change– Less than Predicted

• Rate of Distillation– Observed: Sporadic, ~94 ml/min– Theoretical: Decreasing, 215-200 ml/min

Next Steps

• Resolve Inconsistencies

• Conduct More Data Runs

• Estimate Heat Losses

• Compare Column Performance to Predictions

Distillation ColumnDesign Project

M. O. C. Project Engineering Department

Team Members

Michael Hobbs

Michael McGann

Marc Moss

Brad Parr

Brian Vandagriff

Topics of Discussion

• Problem Statement

• Recommended Design

• McCabe-Thiele Diagram

• Design Specifications

• Combined Flow Diagram

Topics, cont.

• Method of Design

• Raoult Method

• van Laars Method

• Sieve Tray Efficiency

• Optimum Reflux Ratio

• Conclusions

Problem Statement

To design a new ethylene purification column to work with the advanced catalytic cracking operation that produces ethylene for manufacture of specialty products

PROCESS

AREA B

PROCESS

AREA C

PROCESS

AREA C

EAST AVENUE

WEST AVENUE

BROADWAY

EMPLOYEE PARKING

VISITOR PARKING

OFFICE

T1

T2

T3 T4 FS1

B2

B1

CT1

CT2

T5 T6

CO

LU

MN

ST

RE

ET

ST

RE

ET

3RD

ST

RE

ET

2ND

1ST

DISTILLATE

CWS

SS

Recommended Design

Design analysis included:

• number of trays

• tray diameter

• pipe diameter for each stream

• pump selection (if necessary)

McCabe-Thiele Diagram

Fortran program “Distil.exe” was used to generate data that was plotted in Excel to give McCabe-Thiele Diagram. Diagram shows equilibrium line, operating line, feed line, separation line, and the stepped off stages.

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

x

y

Feed tray = 73

Quantity Description Each Cost System81 23.70 ft. diameter Sieve-trays $4,800.00 $388,800.00

107 ft 8-inch diameter pipe (SS) $175.00 $18,593.75 distillate10 ft 3-inch diameter pipe (SS) $58.00 $580.00 bottoms10 ft 16-inch diameter pipe (SS) $310.00 $3,100.00 feed44 ft 18-inch diameter pipe (SS) $390.00 $17,062.50 CWS63 ft 36-inch diameter pipe (SS) $660.00 $41,250.00 SS100 ft 12-inch diameter pipe (SS) $290.00 $29,000.00 reflux

1 Chemical inline ductile iron casing, vertical motor $1,500.00 $1,500.00 bottoms1 Chemical inline ductile iron casing, horiz. motor $1,800.00 $1,800.00 distillate1 AVS Chemical horizontal ductile iron casing $2,100.00 $2,100.00 reflux

Design Specifications

Combined Flow Diagram

Shows system diagram with both qualitative and quantitative information.

DistillateD = 182 Mlb/hxD = 0.999

Bottoms ProductB = 38 Mlb/hxB = 0.089

Condenser

Splitter

Reboiler

Cold Water Supply = 378.1 Mlb/hT = 80 oF

Steam Supply = 119.7 Mlb/hP = 20 psig

Cold Water ReturnT = 120 oF

Water Return

L = 546 Mlb/h

V’ = 546.5 Mlb/h

L’ = 585.2 Mlb/h

V = 719.5 Mlb/h

FeedF = 220 Mlb/hxF = 0.85f = 1

EM = 80%

81

stages

Design Requirements

• feed : 220 M lb/hr of vapor, 85% ethylene

• product: 182 M lb/hr, 99.9% ethylene

Raoult Model

• Assumes ideal behavior

• System deviated slightly from ideality at low compositions

0.0

0.2

0.4

0.6

0.8

1.0

0.0 0.2 0.4 0.6 0.8 1.0x

y

Actual Data

Operating Line Equilibrium Line

van Laars Model

• Assumes all non-ideal behavior in the liquid

• Shows an improved correlation between model and actual data

0.0

0.2

0.4

0.6

0.8

1.0

0.0 0.2 0.4 0.6 0.8 1.0x

y

Operating Line

Equilibrium Line

Actual Data

Sieve Tray Efficiency

Sieve trays were chosen because they are cheaper, more efficient, and have a larger operating range than other types of tray designs

Fg = Ut g

1/2

Optimum Reflux Ratio

The optimum reflux ratio was determined by calculating the annual operating costs for columns with varying reflux ratios. A plot of annual cost vs. reflux ratio was made; the optimum value is the one that corresponds to the minimum point on the curve.

2.E+06

3.E+06

3.E+06

4.E+06

4.E+06

5.E+06

2.5 3.0 3.5 4.0 4.5 5.0

Reflux Ratio

Annu

al C

ost,

$

Minimizing Annual CostThree options each were given for heating the reboiler and cooling the condenser.

Heating: steam at 20 psig ($1/1000lb)

steam at 100 psig ($3/1000lb)

electrical heating ($0.12/kWh)

Cooling: cooling water ($0.50/1000gal)

domestic water ($1.80/1000gal)

refrigerant ($5/ton-day)

Minimizing Annual Cost

Total annual costs (based on 7200 hr/yr) were calculated for each of the options. The lowest priced option for each was selected.

• heating: steam at 20 psig

• cooling: CWS

Conclusions

The column designed contains 81 trays, with a diameter of 23.7 ft and 12 inch spacing between the trays. It will require an initial start-up cost of $3.01 million, and a present worth of $17.14 million over a projected 11 year operational life.

Ultimate Tennessee Corn whiskey

Skip Pond, EI

Michael McGann

Topics of Discussion

• Past Accomplishments (Section 200)• Current Work (Section 300)• Next Steps

Revised Problem Statement

• Basis: 500,000 gallons finished product

• Areas of focus– Section 200 (Cooking/Fermenting)– Section 300 (Distillation)– Section 900 (Boiler/Cooling Tower)

Revised Problem Statement

• Customer requirements– Operational Schedule Comparison– Automated Control Investigation– Onsite Boiler/Cooling Tower– Pre-Distillation Settling Tank

• Liquid Feed Column with Flash Tank

Section 200: Cooking/Fermenting

Equipment Specifications

No. Item and Description Size Mat'l Const. 1990 unit cost M&S Purchase Price1 S-211Yeast Dry Storage 5000 gal SS 40,000.00$ 0.122 44,880.00$ 2 T-211-212 Mash Tub w/ Bottom Filter(Cooking) 8500 gal. SS 53,528.00$ 0.122 120,116.83$ 7 T-221-227 Fermentation Tank 20000 gal. SS 45,900.00$ 0.122 360,498.60$

1MP-21 Mash Tub Pump and Motor (3/16 SS Centrifugal) 1000 gpm SS 9,216.00$ 0.122 10,340.35$

Total = 535,835.78$

Equipment Specifications for Section 200 (Cooking and Fermentation)

Mash Tank Material Balance

Inputs

• corn: 259 bushels

• rye: 44.3 bushels

• malt: 37.5 bushels

• H2O: 10000 gal.

*1 bushel = 55 pounds

Outputs

• spent grain: 340.8 bushels

• H2Ovap: 2500 gal.

• wort: 7500 gal.

Mash Cooking Energy Balance

qconvectionT, 132oFqx qx

qx + qconvection=1500000Btu/hr

qwater=11293497 Btu/hr

250psia SteamT=401oFh=1202.1 Btu/hr =25,823 lbs/hr

250psia Condensed SteamT=401oFh = 376.02Btu/hr

Heat Exchanger Coils

m

Operational Schedule

DayTank Mon. Tues. Wed. Thurs. Fri. Sat. Sun.T-211 Cook Mash Cook Mash Cook Mash Cook Mash Cook Mash Cook Mash Cook MashT-212 Cook Mash Cook Mash Cook Mash Cook Mash Cook Mash Cook Mash Cook MashT-221 Fill/Ferm Ferment2 Ferment3 Ferment4 Distill Clean IdleT-222 idle Fill/Ferm Ferment2 Ferment3 Ferment4 Distill CleanT-223 Clean Idle Fill/Ferm Ferment2 Ferment3 Ferment4 DistillT-224 Distill Clean Idle Fill/Ferment Ferment2 Ferment3 Ferment4T-225 Ferment4 Distill Clean Idle Fill/Ferm Ferment2 Ferment3T-226 Ferment3 Ferment4 Distill Clean Idle Fill/Ferm Ferment2T-227 Ferment2 Ferment3 Ferment4 Distill Clean Idle Fill/Ferm

Distillation Column

DistillateD = 16 klbxD = 0.55

Bottoms ProductB = 13 klbxB = 0.01

Condenser

Splitter

Reboiler

Cold Water Supply =T =

Steam Supply =P =

Cold Water ReturnT =

Water Return

L =

V’=

L’=

V =

FeedF = 147 klbxF = 0.07f = 1

Tray Spacing = 12 in

EM =11

stages

Feed Tray Material Balance

• L’=RD*D + (1-f)*F

• V’=D*(RD+1) - f*F

Condenser Material Balance

• L=RD*D

• V=D*(RD+1)

Next Steps

• Post Distillation Flash Tank

• Boiler/Cooling Tower Section

• Final cost analysis and reporting