Finalreport10bch0053

VIT U N I V E R S I T Y VELLORE – 632 014

SCHOOL OF MECHANICAL AND BUILDING

SCIENCES

CHEMICAL ENGINEERING DIVISION

DESIGN PROJECT

ON

ADIPIC ACID

By:- SHIVIKA AGRAWAL(10BCH0053)

NIKHIL NEVATIA(10BCH0038)

SATISH M. PILLAI(10BCH0072)

VI Semester

B. Tech. Mechanical Engg. Spec. in Chemical Processes

Design Project Record

2013

2

VIT U N I V E R S I T Y VELLORE – 632 014

SCHOOL OF MECHANICAL AND BUILDING SCIENCES

CHEMICAL ENGINEERING DIVISION

Certified that this is the bonafide record of work done by

1.SHIVIKA AGRAWAL(10BCH0053)

2.NIKHIL NEVATIA(10BCH0038)

3.SATISH M. PILLAI(10BCH0072)

Of Sixth Semester students of B.Tech Mechanical Engineering with Specialization

in

Chemical Processes during the year 2012.

Project guide

Prof. Pandurangan K.

3

ACKNOWLEDGEMENT We would like to express our deep gratitude to all those who gave us the

opportunity towork on this design project. We want to thank the Department of

Chemical Engineering of VIT University, Vellore for helping us. We have

furthermore to thank the faculties Prof. David K Daniel, Prof. Chitra D., Prof.

Anand Gurumoorthy, Prof. Aslam Abdullah and Prof. Nirmala G.S. who reviewed

us periodically and encouraged us to go ahead with the work.

We are deeply indebted to our guide Prof. Pandurangan K. who helped us in

stimulating suggestions and supported us with all the valuable guidance.

4

PREFACE

This design project includes various aspects of a chemical product development

right fromthe market condition evaluation to the estimation of cost of the plant

setup.

Chapter 1 deals with the introduction to the product (adipic acid) – its properties

both physical and chemical. It also provides the application of adipic acid in

various other areas.

Chapter 2 contains a study of adipic acid in the global as well as Indian market.

The gap between demand and supply is studied and used to set a bar for the

production rate for the plant.

Chapter 3 has a brief explanation of various available processes for the

manufacture of the adipic acid. A comparison is also done between the chosen

process and the other available processes. The detailed process description is also

given for the selected process.

Chapter 4 includes material balance over all the equipments used in the plant for a

production of 100 TPD of adipic acid. Both component-wise and overall mass flow

rate has been provided. The mol%, and wt.% is also provided for each component

and the molar flow rate of each is included too.

Chapter 5 contains enthalpy balance for all the streams in and out of each

equipment in the plant. The utilities requirement are also calculated, stating the

amount of cooling water and steam required for daily running of the plant.

Chapter 6 contains the mechanical design of a heat exchanger using Kern’s

method.

Chapter 7 provides cost estimation for the Heat exchanger.

Chapter 8 provides MSDS for adipic acid.

5

CONTENTS

Certificate 2

Acknowledgement 3

Preface 4

1. Introduction 6

2. Market Analysis 8

3. Process Selection 13

4. Material Balance 21

5. Energy Balance 29

6. Equipment Design 42

7. Cost Estimation 52

8. MSDS for Adipic Acid 54

Reference

Process Flow Sheet 21

6

CHAPTER 1

INTRODUCTION

Adipic acid is the organic compound with the formula (CH2)4(COOH)2. From the

industrial perspective, it is the most important dicarboxylic acid. About 2.5 billion

kilograms of this white crystalline powder are produced annually, mainly as a

precursor for the production of nylon. Adipic acid otherwise rarely occurs in

nature.

Molecular formula C6H10O4

Molar mass 146.14 g mol−1

Appearance White crystals (monoclinic)

Density 1.36 g/cm3

Melting point 152.1 °C, 425 K, 306 °F

Boiling point 337.5 °C, 611 K, 640 °F

Solubility in water fairly soluble

Acidity (pKa) 4.43, 5.41

USES

• Adipic acid is used in nylon 6,6 fibres and resins, which account for nearly

65% of output.

• Used to produce polyurethanes.

http://en.wikipedia.org/wiki/Organic_compound

http://en.wikipedia.org/wiki/Dicarboxylic_acid

http://en.wikipedia.org/wiki/Nylon

7

• As a food ingredient in gelatins, desserts and other foods that require

acidulation.

• Incorporated into controlled-release formulation matrix tablets to obtain pH-

independent release for both weakly basic and weakly acidic drugs.

APPLICATIONS

• In manufacturing plasticizers and lubricants,in making polyester polyols for

polyurethane systems.

• Adipic acid derivatives, acyl halides, anhydrides, esters, amides and nitriles,

are used in making target products such as flavoring agents, internal

plasticizers, pesticides, dyes, textile treatment agents, fungicides, and

pharmaceuticals.

• Nylon 6, 6 fiber is used in apparel, especially ladies' hosiery, sleepwear, and

underwear, carpets, and home furnishings. Other nylon 6,6 fiber uses include

tire cord, fishing line, brush bristles, and in tough fabrics for parachutes,

backpacks, luggage, and business cases.

8

CHAPTER 2

MARKET ANALYSIS

DEMAND

Global adipic acid (ADA) demand is estimated at 3.3 million metric tons in

2012 and is growing at 3–5% per year.China is the world’s largest importer

of adipic acid. Europe stands tall as the largest worldwide market for adipic

acid. Asia-Pacific, led by rapid advancements from China is slated to be the

fastest growing market for Adipic Acid. In 2008, global demand for adipic

acid was about 2.5-mt, which rose to about 2.57-mt by 2009.In W. Europe,

consumption of adipic acid for nylon 66 fibres, nylon 66 engineering resins

and polyester polyols have grown at an average rate of approximately 2%

per year during 2005-2010.In Japan, consumption for nylon 66 fibres have

grown at an average rate of 5.9% per year during 2005-2010.Consumption

for production of polyester polyols, which are used in hot-melt adhesives for

shoe soles and other products, has grown swiftly in Asia. Asia is becoming a

potential market for adipic acid due to its increasing demand for

polyurethane and polyamide. Overall demand increased to 6 % per year till

2010.

9

INDIAN SCENARIO

A new single-step process for adipic acid production was developed by a

consortium of the Indian Institute of Petroleum (IIP) and Adarsh Chemicals &

Fertilizers Ltd. The process involved oxidation of cyclohexane using a modified,

recyclable cobalt catalyst and was said to be environmentally friendly since no

nitric acid or nitrous oxide is involved. Currently, India has negligible production

of adipic acid, and almost the entire requirement is met through imports. Imports of

adipic acid in 2008-09 are estimated at about 9,685-tons.

10

PRODUCTION CAPACITY AND SUPPLY

In the present scenario, there are about 23 adipic acid production units worldwide,

with majority existing in the developed western countries or developing markets.

In 2010, the global Adipic acid production level was recorded at over 2,800 kt,

with the United States making up the largest share at over 30% of the global

output. Other producing countries include Brazil, Canada, China, France,

Germany, Italy, Japan, Korea, Singapore, Ukraine, and United Kingdom. Most of

these countries have only one adipic acid plant. By-product nitric acid is used

primarily to make synthetic commercial fertiliser. The production technology of

11

adipic acid for long has been controlled in the hands of multinationals such as

DuPont. In 2004, total installed capacity for adipic acid in the world was 2.74-

mtpa.DuPont alone accounted for a capacity of 1.1-mtpa,

accounting for 40% of the world total. Solutia (USA) and Rhodia(France) were

other dominant producers.The three, together, accounted for close to 70% of world

total. Producers in other regions of the world included Asahi Chemical (Japan),

Bayer and BASF (both in Germany).

12

FUTURE SCENARIO

Development of newer applications of Adipic Acid is poised to increase global

production levels. In the US, adipic acid demand for nylon 66 fibre, nylon 66

engineering resin and polyester polyols is expected to increase by 1.7-3.2% per

year, while demand in adipate-based plasticizers will remain flat. In W. Europe,

consumption of adipic acid for nylon 66 fibres, nylon 66 engineering resins and

polyesterpolyols will grow at an averagerate of approximately 2%per year during

2005-2010.In Japan, consumption for nylon 66 fibres will grow at an average rate

of 5.9% per year during 2005-2010. Consumption for nylon 66 resins will grow at

2.5% per year, while use for polyester polyols will decrease by 1% per year, and

demand for plasticizers will decrease by 1.2% per year. China is expected to

exhibit the fastest growth in the world. Consumption for production of polyester

polyols, which are used in hot-melt adhesives for shoe soles and other products,

has grown swiftly. PetroChina Liaoyang Petrochemical’s second adipic acid plant

came on stream in 2004. The global market for Adipic Acid is projected to reach

over 6 billion pounds by the year 2017. Growth in the market is chiefly driven by

an increase in demand from end-use segments, particularly in emerging markets of

Asia-Pacific and Middle East.

13

CHAPTER 3

PROCESS SELECTION

Adipic acid can be manufactured by one of the following routes:

From cyclohexane via cyclohexanone and cyclohexanol (KA oil) by

oxidation(the conventional process);

From benzene via cyclohexanol by partial hydrogenation and

hydration(Asahi Chemical process);

From phenol; and

From butadiene by carboalkoxylation(a process not yet commercialized).

Adipic acid has historically been manufactured from either cyclohexane or phenol,

but shifts in hydrocarbon markets have nearly resulted in theelimination of phenol

as a feedstock in the U.S. This has resulted in experimentation with alternative

feedstock, which may have commercial ramifications. The cyclohexane-based

process accounts for about 93% of production capacity, and the other two for 4%

and 3%, respectively. Cyclohexane is expected to retain its dominant position as

the feedstock of choice for adipic acid manufacture in the coming decade, although

the butadiene-based production via carboalkoxylation may be competitive in

production cost, depending on by-product credits taken for butadiene use as fuel.

While virtually all process technologies are based on oxidation on KA with nitric

acid, there are many variations on this theme. In addition to these established

approaches, there have been many attempts over the years to improve adipic acid

production technologies by eliminating the need for nitric acid by using air, oxygen

or hydrogen peroxide, as the oxidant. Recently, researchers at Nagoya University

developed a new method, which substitutes 30% aqueous hydrogen Peroxide for

nitric acid, producing adipic acid in over 90% yield and eliminating N2O as a by-

product. However, commercial application of this process will depend on finding

cheaper ways to produce hydrogen peroxide.

14

PROCESS TECHNOLOGIES

• LABORATORY SCALE PROCEDURES

I. High peroxide process Oxidation of cyclohexane to produce cyclohexanone (a ketone, K)

and cyclohexanol (an alcohol, A).This ketone-alcohol (KA) mixture is

converted in the second step to adipic acid by oxidation with H2O2 .

ADVANTAGES

Over 90% yield

N2O as a by-product eliminated

Reduced temperatures and pressures.

DISADVANTAGES

Not cost effective, commercial application of this process will depend

on finding cheaper ways to produce hydrogen peroxide.

II. Biosynthesis using E. coli as a host(Draths-Frost syntheses)

Non toxic Glucose is substrate which is converted into cis,cis muconic

acid using a single genetically modified microbe such as E.Coli.Later this

cis,cis muconic acid is hydrogenated to yield adipic acid.

ADVANTAGES

Generation of toxic intermediates and evironment - damaging by

products is avoided.

Renewable feedstock is used.

Water is used as a primary solvent.

DISADVANTAGES

Still in conception.

15

Large scale incorporation requires research(e.g. specialised

equipments, utilities etc.)

Expensive

III. Adipic acid production via butadiene carbonylation

Hydroxycarbonylation of butadiene to primarily 3-pentenoic acid

using a palladium/ crotyl chloride catalyst system has shown a 3-

pentenoic acid selectivity of 92 mole percent.

Further conversion of pentenoic acids by reaction with carbon

monoxide and methanol by the use of a palladium, ferrocene,

phosphorous ligand catalyst system has demonstrated selectivity to

dimethyl adipate of 85 mole percent. The dimethyl adipate is then

readily hydrolyzed to adipic acid.

ADVANTAGES

Cheap raw materials

DISADVANTAGES

Multi-reaction steps, and thus large investment requirements.

16

• COMMERCIAL TECHNOLOGY

I. The KA process(from cyclohexane) using nitric acid The main commercial route for the production of KA is the

oxidation of cyclohexane ,employed by producers like Du

Pont, BASF, and Stamicarbon.

Oxidation of cyclohexane to produce cyclohexanone (a

ketone, K) and cyclohexanol (an alcohol, A)

This ketone-alcohol (KA) mixture is converted in the second

step to adipic acid by oxidation with 40-45% nitric acid in the

prescence of copper and vanadium catalysts.

17

The wet adipic acid crystals are separated from water and nitric

acid.The product is dried and cooled before packaging and

shipping.

ADVANTAGES

By product nitric acid is recycled in the process itself and can also be

shipped

High yield as well as cost effective.

DISADVANTAGES

Gaseous NOx effluents are released that are harmful to the

enviroment.

II. Adipic Acid production via benzene partial

hydrogenation/cyclohexene hydration to cyclohexanol

Also named as Asahi Chemical process, licensed to China

Shenma.

Partial hydrogenation of benzene to cyclohexene over a

complex ruthenium catalyst under high pressure

The cyclohexene is subsequently hydrated under moderate

conditions in the presence of a slurry catalyst, consisting mainly

of zeolites, to give cyclohexanol.

And the subsequent oxidation by nitric acid/ boric acid yields

adipic acid.

ADVANTAGES

Have a potential advantage of recycling hazardous halogenate

compounds.

18

DISADVANTAGES

Deactivation of the catalyst

Partial dehydrogenation of cyclohexane or dehydrohalogenation of

cyclohexyl halides

III. Adipic acid production via Butadiene Carbonylation

Two-step carbomethoxylation of butadiene with CO and MeOH using

Homogeneous Co catalyst. Used by BASF

Two-step dihydrocarboxylation of butadiene using catalyst Pd, Rh and

Ir. Used by Du Pont.

ADVANTAGES

Suppression of lower carboxylic acids

DISADVANTAGES

Catalyst recovery and recycle

Very high pressures

Costly extraction procedure

IV. The Alphox process

Solutia (formerly Monsanto), developed a one-step process (AlphOx),

to manufacture phenol from benzene, using nitrous oxide for the

oxidation step.

Thus, by coupling phenol production and adipic acid production,

Solutia has developed a process with no net production of nitrous

oxide

ADVANTAGES

Very good production economics for both phenol and adipic acid.

This route closes the nitrogen loop at adipic acid plants by recycling

and reusing the nitrous oxide off-gas to create phenol,rather than

destroying it.

19

DISADVANTAGES

A relatively small phenol plant requires a world-scale adipic acid

plant for its N2O supply.

V. Aerial oxidation of cyclohexane (solvent-free clean technology

route)

Used by BASF only

One-step process, 100-130oC, 1.5 MPa, air and the catalyst is solid

FeAlPO-31.

ADVANTAGES

Molecular O2 (air) as oxidant

No green house gas (N2O)

No corrosive solvents or promoters

Ease of catalyst recycle and recovery

Low processing costs

DISADVANTAGES

Long reaction time (24 h)

20

The process selected by us is the KA(from cyclohexane)

using nitric acid. We chose this one as it was not patented

and it is a very convenient and economical process, used for

the production of adipic acid by almost all the companies

like Du Pont, BASF, Asahi etc.

FIG: PROCESS FLOW SHEET

21

CHAPTER 4

MATERIAL BALANCE

Now we will perform mass balance on above given process flow sheet taking basis

as 100 tons/day. There is only one Adipic acid plant in India, that is Adarsh

Chemicals, Surat, Gujarat.It produces meagre amount of adipic acid due to which

we have to import most of it. Hence we aimed to set up a plant to reduce the

imports of the acid.

BASIS: 100 tons/day

Performing material balance on reactor 1

Stoichometric requirement

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

Cyclohexanone 14.25573651 1399.200538

Cyclohexanol 14.25573651 1427.854569

Nitric acid 21.38360476 1347.1671

Actual input

Considering 95% conversion ( from literature)

Actual input of cyclohexane and cyclohexanol is 14.255/.95 & 14.255/.95 kmol/hr

respectively.

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

Cyclohexanone 15.00603843 1472.842672

Cyclohexanol 15.00603843 1503.004809

hno3(60%) taken 6:1

with ka oil

102.6413029 6466.40208

h2o along with hno3 68.46174901 1232.311482

ONOHADIPICACIDHNOONECYCLOHEXAN 223 75.075.05.1

22

TOTAL INPUT

Molar flow rate= 15.0060+15.0060+102.6413+68.4617 =201.1151287 kmol/hr

Mass flow rate = 1472.84+1503.004+6466.40+1232.311= 10674.56104 kg/hr

Output

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

adipic acid 14.25573651 2083.333333

unreacted ka 15.75634035 1576.646943

hno3 81.2576981 5119.23498

h2o 79.15355139 1424.763925

n2o 10.69180238 470.4393048 TOTAL OUTPUT

Molar flow rate = 14.255+15.756+81.257+79.153+10.691 = 201.1151287

kmol/hr

Mass flow rate = 2088.33+1576.64+5119.23+1424.76+470.43 = 10674.41849

kg/hr.

Performing material balance on reactor 2

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

adipic acid 14.25573651 2083.333333

unreacted ka 15.75634035 1576.646943

hno3 81.2576981 5119.23498

h2o 79.15355139 1424.763925

n2o 10.69180238 470.4393048

Total molar flow rate= 14.255+15.756+81.257+79.153+10.691= 201.1151287

kmol/hr

OHONADIPICACIDHNOOLCYCLOHEXAN 223 22

23

Total mass flow rate= 2083.33+1576.646+5119.234+1424.763+470.439=

10674.41849 kg/hr

Output

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

adipic acid 28.51147302 4166.666667

h2o 107.6650244 1937.970439

n2o 24.94753889 1097.691711

unreacted ka 1.500603843 148.7923741

hno3 52.74622508 3323.01218

Total molar flow rate= 28.511+107.665+24.9475+1.500+52.74= 215.3708652

kmol/hr

Total mass flow rate= 4166.667+1937.970+1097.691+148.792+3323.012=

10674.13337kg/hr

Performing material balance on NOX bleacher

Assuming 10% excess oxygen to be used and air contains 79% nitrogen and 21%

oxygen by mole %

Input

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

h20 entering 107.6650244 1937.970439

adipic acid entering 28.51147302 4166.666667

n2o entering 24.94753889 1097.691711

oxygen entering 41.16343917 1317.230053

n2 entering 154.8529378 4335.882259

hno3 entering 52.74622508 3323.01218

unreacted ka 1.500603843 148.7923741

222 25.1 NOOON

24

Total molar flow rate= 107.665+28.511+24.947+41.163+154.852+52.74+1.500=

411.3872422 kmol/hr

Total mass flow rate=

1937.970+4166.666+1097.691+1317.230+4335.8822+3323.012+148.792=16327.

24568kg/hr

Output

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

h2o exiting 107.6650244 1937.970439

adipic acid exiting 28.51147302 4166.666667

no2 exitng 49.89507778 2295.173578

o2 exiting 3.742130833 119.7481867

n2 exiting 154.8529378 4335.882259

hno3 exiting 52.74622508 3323.01218

unreacted ka 1.500603843 148.7923741

Total molar flow

rate=107.665+28.511+49.89+3.74+154.85+52.74+1.500=398.9134728kmol/hr

Total mass flow

rate=1937.97+4166.66+2295.17+119.74+4335.88+3323.012+148.79=16327.2456

8kg/hr

Performing material balance on NOX Absorber

Input

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

no2 entering 49.89507778 2295.173578

water required 16.63169259 299.3704667

Total molar flow rate= 49.895+16.631= 66.52677037kmol/hr

NOHNOOHNO 322 23

25

Total mass flow rate= 2295.173+299.370=2594.544045 kg/hr

Output

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

hno3 formed 33.26504836 2095.698046

no formed 16.6150609 498.451827

Total molar flow rate= 33.265+16.615=49.88010926 kmol/hr

Total mass flow rate= 2095.698+498.451= 2594.149873 kg/hr

Performing material balance on crystallizer

Feed stream is containing 43.5% by weight adipic acid which is to be cooled from

60 C to 20 C.

26

The solubility chart for adipic acid is as shown below:

Input

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

adipic acid 28.51147302 4166.666667

h2o 107.6650244 1937.970439

unreacted ka 1.500603843 148.7923741

hno3 52.74622508 3323.01218

Total molar flow rate = 28.511+107.665+1.500+52.746= 190.4233263 kmol/hr

Total mass flow rate= 4166.66+1937.97+148.79+3323.01= 9576.44166 kg/hr

27

Output

Let mass of adipic acid crystals formed be x kg/hr

Mass of adipic acid in mother liquor = (9576.441-x)*(4/104) kg/hr

Therefore applying material balance on crystallizer ,we get

Solubility at 20 C(from graph) = 4g adipic acid/100 g water

4166.667 = x + (9576.441-x)*(4/104)

x = 3950.275667 kg/hr

therefore mass of adipic acid in mother liquor = (9576.441-3950.275)*(4/104) =

216.390 kg/hr

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

adipic acid crystals 27.03076274 3950.275667

h2o 107.6650244 1937.970439

unreacted ka 1.500603843 148.7923741

hno3 52.74622508 3323.01218

adipic acid in mother

liquor

1.480710276 216.3909997

Total molar flow rate = 27.030+107.665+1.500+52.746+1.480 = 190.4233263

kmol/hr

Total mass flow rate = 3950.275+1937.970+148.792+3323.012+216.390 =

9576.44166 kg/hr

Performing material balance on Concentrator

We need 60% HNO3 in our process, so we need to concentrate 44.6% HNO3 in

input stream to 60% HNO3 by evaporating excess water.

28

Input

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

h2o 107.6650244 1937.970439

unreacted ka 1.500603843 148.7923741

hno3 86.01127344 3323.01218

adipic acid in mother

liquor

1.480710276 216.3909997

Total mass flow rate = 1937.970+148.7923+3323.0121+216.390 = 5626.165993

kg/hr

Output

SPECIES MOLAR FLOW

RATE(kmol/hr)

MASS FLOW

RATE(kg/hr)

h2o evaporated 50.32417545 905.8351581

recycle stream - 4720.330835

Total mass flow rate = 905.835+4720.33 = 5626.165993 kg/hr

29

CHAPTER 5

ENERGY BALANCE

After the mass balance is performed, we go for energy balance on the same flow

sheet.

REACTOR 1

Enthalpy Balance on Streams in and out of the Reactor 1:

Feed in (at a temperature of 30

oC):

Calculating Cp mix for the inlet stream:

COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K) AT

30 oC

(2)

MOLE

FRACTIONS

Cyclohexanol 2.099 0.074614

Cyclohexanone 1.926 0.074614

Nitric acid 1.745 0.510361

Water 4.181 0.340411

Total Cp mix = (2.099*0.074614)+( 1.926*0.074614)+( 1.745*0.510361)+(

4.181*0.340411)

= 2.614159134

Mass of the feed stream= 10674.56104 Kg/hr

Temperature=303 K

TOTAL INPUT HEAT= 2.614159134*303*10674.56104

= 8455215.38 kJ/hr

Feed out (at a temperature of 70oC):

30

Calculating Cp mix for the outlet stream:

Total Cp mix =

(2.392*0.070883)+(2.284*0.0037)+(2.033*0.0746)+(1.738*0.404036)+(4.187*0.3

93573)+(0.922*0.053163)

= 2.745174797 kJ/Kg.K

Mass of the feed stream=10674.56104Kg/hr

Temperature=343 K

TOTAL OUTPUT HEAT= 2.745174797 *343*10674.56104

=10051112.83kJ/hr

The reaction taking place in the reactor 1:

Cyclohexanone AA ΔHR= - 172 Kcal/mol

=-719957.6kJ/mol

COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 70 oC

(2)

MOLE FRACTIONS

Adipic Acid 2.392 0.070883



Nitric acid 1.738 0.404036

Water 4.187 0.393573

Nitrous Oxide 0.922 0.053163

ONOHADIPICACIDHNOONECYCLOHEXAN 223 75.075.05.1

31

=-719957.6*14.25573651*0.95kJ/hr

HEAT OF REACTION =-9750349.551kJ/hr

Where 0.95 is the percentage conversion

Heat of condensing steam from the steam table at 100oC=2258

Mass of steam required= (10051112.83+9750349.551-8455215.38)/2258

= 5024.910098Kg/hr

Mass of steam required= 5024.910098Kg/hr

REACTOR2

Enthalpy Balance on Streams in and out of the Reactor 2:

Feed in (at a temperature of 70oC):

Input heat of the reactor 2 will be same as the output heat of the reactor 1.

Hence

TOTAL INPUT HEAT= 2.745174797 *343*10674.56104

=10051112.83kJ/hr



COMPONENTS IN (1)

32

THE STREAM SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 90 oC

(2)

MOLE FRACTIONS

Adipic acid 2.42 0.1324



Nitric acid 1.737 0.2449

Water 4.207 0.4999

Nitrous oxide 0.939 0.1158

Total Cp mix =

(2.42*0.1324)+(2.346*0.0037)+(2.086*0.0037)+(1.737*0.2449)+(4.207*0.4999)+

(0.939*0.1158)

= 2.882666807kJ/Kg.K


Temperature=363 K

TOTAL OUTPUT HEAT= 2. 882666807 *363*10674.13337

=11169499.1kJ/hr

The reaction taking place in the reactor 2:

Therefore

ΔHR= - 215 Kcal/mol

=-899947kJ/mol

OHONADIPICACIDHNOOLCYCLOHEXAN 223 22

33

=-899947*14.25573651*0.95kJ/hr

HEAT OF REACTION =- 12187936.94kJ/hr

Where 0.95 is the percentage conversion

Heat of condensing steam from the steam table at 100oC=2257

Mass of steam required= (11169499.1+12187936.94-10051112.83)/2257

= 5892.968647Kg/hr

Mass of steam required= 5892.968647Kg/hr

NOX BLEACHER

Assuming 100% conversion

Assuming that the air enters the bleacher at 90 oC.

Enthalpy Balance on Streams in and out of the Bleacher:


oC):


COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 90 oC

(2)

MOLE FRACTIONS

Water 4.207 0.261712

Adipic Acid 2.42 0.069306

Nitrous oxide 0.939 0.060642

Oxygen 0.930 0.10006

Nitrogen 1.042 0.376416

Nitric acid 1.737 0.128216



34

Total Cp mix = (4.207*0.261712)+(2.42*0.069306)+( 0.939*0.060642)+(

0.930*0.10006)+(1.042*0.376416)+(1.737*0.128216)+(2.346*0.0037)+(2.086*0.0

037)

= 2.041758073

Mass of the feed stream= 16327.24568Kg/hr

Temperature=363 K

TOTAL INPUT HEAT=2.041758073*363*16327.24568

=12101071.7 kJ/hr



COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 90 oC

(2)

MOLE FRACTIONS

Water 4.207 0.269896


Nitrogen dioxide 0.848 0.125077

Oxygen 0.930 0.009381

Nitrogen 1.042 0.388187

Nitric acid 1.737 0.132225



Total Cp mix =

(4.207*0.269896)+(2.42*0.071473)+(0.848*0.125077)+(0.930*0.009381)+(1.737

*0.132225)+(1.042*0.388187)+(2.346*0.0037) +(2.086*0.0037)

= 2.065700182kJ/Kg.K

35


Temperature=363 K

TOTAL OUTPUT HEAT= 2.065700182*363*16327.24568

=12242971.56kJ/hr

The reaction taking place in the bleacher:

Heat of reaction =20754.21* 24.94753889KJ/hr

= 517766.4611 KJ/hr

HEAT OF REACTION =-517766.4611 kJ/hr

Since the conversion is 100%.

Water enters at 30oC and leaves at 40

oC.

Specific heat of water at 90oC=4.207

Mass of cooling water required to maintain the temperature= (12101071.7 -

12242971.56-517766.4611 )/(4.207*10)

= 15680.20726Kg/hr

Mass of cooling water required= 15680.20726Kg/hr

NOX ABSORBER

Enthalpy Balance on Streams in and out of the Absorber:


oC):

222 25.1 NOOON kmolKJHR /21.20754

36


COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 90 oC

(2)

MOLE FRACTIONS

Nitrogen Dioxide 0.848 0.75

Water 4.207 0.25

Total Cp mix = (0.848*0.75)+(4.207*025)

= 1.6877kJ/kg.K


Temperature=363 K

TOTAL INPUT HEAT=1.6877*363* 2594.544045

= 1589555.841 kJ/hr



COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 90 oC

(2)

MOLE FRACTIONS

Nitric acid 1.737 0.6669

Nitric oxide 0.995 0.3331

Total Cp mix = (1.737*0.6669)+(0.995*0.3331)

= 1.489839852kJ/kg.K


37

Temperature=363 K

TOTAL OUTPUT HEAT=1.489839852*363* 2594.149873

= 1402947.034 kJ/hr

The reaction taking place in the Absorber:

Heat of reaction =-(34868.64* 49.89507778)/3KJ/hr

= -579924.5016KJ/hr

HEAT OF REACTION =- 579924.5016kJ/hr

Since the conversion is 100%.


oC.

Specific heat of water at 90oC=4.207

Mass of cooling water required to maintain the temperature= (1589555.841 -

1402947.034 -579924.5016 )/(4.207*10)

= 9349.077606Kg/hr


HEAT EXCHANGER

Enthalpy Balance on Streams in and out of the Exchanger:


oC):


NOHNOOHNO 322 23 kmolKJHR /64.34868

38

COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 90 oC

(2)

MOLE FRACTIONS


Water 4.207 0.269896



Nitric acid 1.737 0.132225

Total Cp mix = (2.42*0.071473)+(4.207*0.269896)+(2.346*0.0037)+

(2.086*0.0037)+(1.737*0.132225)

= 3.239609009kJ/kg.K


Temperature=363 K

TOTAL INPUT HEAT=3.239609009*363*9576.44166

= 11261685.38kJ/hr



COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 60 oC

(2)

MOLE FRACTIONS

Adipic Acid 2.378 0.071473

Water 4.18 0.269896



Nitric acid 1.739 0.132225

39

Total Cp mix = (2.378*0.071473)+(4.18*0.269896)+(2.223*0.0037)+

(2.006*0.0037)+(1.739*0.132225)

= 3.217808719kJ/kg.K


Temperature=333 K


=10261447.44kJ/hr


oC.

Average specific heat of water at 90oC and 60

oC =(4.207+4.18)/2=4.1935

Mass of cooling water required = (11261685.38-10261447.44)/(4.1935*10)

=23852.10315Kg/hr


CRYSTALLIZER

Enthalpy Balance on Streams in and out of the Crystallizer:

Feed in (at a temperature of 60oC):

Input heat of the crystallizer will be same as the output heat of the exchanger.

Hence

TOTAL INPUT HEAT=10261447.44kJ/hr



40

Total Cp mix = (2.323*0.141951)+(4.19*0.565398)+(2.058*0.0037)+

(1.9*0.0037)+(1.748*0276995)+(2.323*0.007776)

= 3.21662068kJ/kg.K


Temperature=293 K


=9025507.622kJ/hr

Assuming, that there is no water evaporation.

HEAT OF CRYSTALLIZATION=-213.6 kJ/kg

=-213.6*3950.275667kJ/hr

=-843778.8825 kJ/hr


oC.

Average specific heat of water at 60oC and 20

oC =(4.18+4.19)/2=4.185

Mass of cooling water required = (10261447.44-9025507.622kJ -

843778.8825)/(4.185*10)

=9370.631611Kg/hr

COMPONENTS IN

THE STREAM

(1)

SPECIFIC HEAT

CAPACITY(kJ/Kg. K)

AT 20 oC

(2)

MOLE FRACTIONS

Adipic Acid crystals 2.323 0.141951

Water 4.19 0.565398



Nitric acid 1.748 0.276995

Adipic Acid in mother

liquor

2.323 0.007776

41


CONCENTRATOR

Enthalpy Balance on Streams in and out of the Concentrator: Feed in (at a temperature of 20

oC):

Assuming that the steam enters at 120oC.

Assuming that the evaporator is operated at 1 atm.

Assuming no BPR.

Enthalpy of liquid feed from steam table at 20

oC is 83.9kJ/kg.

HEAT OF FEED=83.9*5626.165993

=472035.3268kJ/hr

Enthalpy of mother liquor from steam table at 100oC is 419.04kJ/kg.

HEAT OF THE RECYCLE STREAM=419.04*4720.330835

=1978007.433kJ/hr

Enthalpy of vapor from steam table at 100oC is 2676.1kJ/kg.

HEAT CARRIED AWAY BY THE VAPOR=2676.1*905.8351581

= 2424105.467kJ/hr

Enthalpy of steam from steam table at 120oC is 2202kJ/kg.

Mass of cooling water required = (2424105.467+1978007.433-472035.3268)/2202

=1784.776373Kg/hr

Mass of steam required=1784.776373Kg/hr

Hence we get the amount of utilities at each stage of production.

42

CHAPTER 6

EQUIPMENT DESIGN

DESIGN OF HEAT EXCHANGER

An exchanger to cool mixture of adipic acid, nitric acid, water and unreacted KA

oil from 90 °C to 60°C. Flow-rate of mixture 9576.44166 kg/hr. Brackish water

will be used as the coolant, with a temperature rise from 30° to 40°C.

Coolant is corrosive, so assign to tube-side.

As brackish water is more corrosive it is preferred on tube side.

Heat load: mc(∆T)= (9576.44/3600)*3.23*30= 257.76 kW

Mass flow rate of water = 257.76/(4.2*(40-30))= 6.13 kg/s

∆Tln= 39.15 C

True temperature difference = 31*Ft= 39.15*0.95= 37.5 C

U = 400 W/m² C

Provisional area= Q/U*∆Tln = 17.184 m²

Tube dimensions:

5/8 inch to 2 inch tubes are most often used.

5/8 to 1 inch is preferred as they have small diameter, more compact and therefore

cheaper exchangers

But for highly fouling fluid larger tubes are preferred

Take a tube of 5/8 inch ID, and OD of 20 mm

43

44

Preferred lengths of tubes for heat exchangers are:

6ft, 8ft, 12ft,16feet.

Therefore take L= 16 feet = 4.83 m

Area of one tube= π*do*L= 0.303 m²

Number of tubes = provisional area/surf. Area of tube = 17.184/0.1515 = 58

As shell side fluid is non-corrosive, take a triangular pitch

Pt=1.25 (od of tube)

Calculation of bundle diameter

= 236.4 mm

45

Bundle diameter clearance:

46

Shell diameter = Ds= 236.4+88.6 mm = 325mm

Tube side coefficient:

Mean water temperature: 35C

Properties of water at that temperature,

Viscosity= 0.715 *10ˉ³ . kf = 0.61 W/mC

Density = 992.4 kg/m³

tubes per pass= 58/2=29

Total flow area= 29* C.S area= 29*(π/4*0.016²) = 0.00582784 m²

Mass flux or water mass velocity = 6.13/0.00582784 = 1051.84 kg/s-m²

reynolds number: 23537.67

prandtl number : 4.92

L/di = 301.875

Correlated eqn. for Nu is :

47

From figure,

Therefore hi = 5920.88 W/m² C

Shell side coefficient :

baffle spacing lb = Ds/5= 325/5 = 65 mm

Tube pitch = 1.25*20 = 25 mm

Cross-flow area = (25-20)/25 *0.325*0.065= 0.004225 m²

Mass velocity, Gs = 9576.441/3600*(1/0.004225) = 629.6147 kg/s m²

Equivalent diameter = 14.4 mm

Mean shell side temperature = (90+60)/2 = 75 C

Density of mixture = 1093.70 kg/m³

Viscocity = 0.074 mNs/m², Kf = 0.48 W/mC, Cp= 3.07 KJ/kgC

48

Reynolds number = Gs*De/µ = 122519.6173, Prandtl number = 4.73

Assuming 25% baffle cut

jh= 2 *10ˉ³

hs = 13640.13 W/m²C

Overall heat transfer coefficient:

49

U = 832.016 W/m² C

Well above assumed value (400W/m2C)

Pressure drop:

On tube side: jf= 3.9*10-3

s

50

= 13.04 kPa

Low value, could consider increasing no. of passes.

On shell side:

jf = 0.05

∆Ps = 89.75 kPa (acceptable)

51

DIMENSIONS OF HEAT EXCHANGER :

No. of tubes = 58

Tube internal diameter = 16mm

Tube outer diameter = 20mm

Tube length = 4.83 m

No. of tube passes = 2

No. of shell passes = 1

Shell diameter = 325 mm

Baffle Spacing = 65 mm

Baffle cut = 25 %

Bundle diameter = 236.4 mm

52

CHAPTER 7

COSTING OF HEAT EXCHANGER

Estimation of cost of shell and tube heat exchange equipment is done as shown

below:

CE = 1.218* CB* FD* FMC* FP

where

CE = exchanger cost

CB = base cost of a carbon steel, floating-heads exchanger, 4 bar design

pressure

FD = design-type cost factor if different from that in CB

FMC = material of construction cost factor

FP =design pressure cost factor

Heat exchanger area A = 17.184 m2

Base cost

= exp [8.821 - .30683ln(17.184) + .0681(ln17.184)2

= $ 4910.786

FD = 1 (Using floating head type)

FP = 1 ( Pressure is below 4 bar)

53

FMC = g1 + g2*lnA

For carbon steel

FMC = 1

Therefore exchanger cost in year 1986 is CE = 1.218* CB* FD* FMC* FP

= 1.218*4910*1*1*1

= $ 5980.38

Using cost indexes for year 1986 and 2011

Exchanger cost in year 2011 is

CE in 2011 = CE IN 1986 *(C I OF 2011/C I OF 1986)^0.68

= 5980*(585.7/325)

= $ 8926.21

CE in 2011 = Rs 482,015.50

The cost of heat exchanger of area 17.184 m2 is Rs 4,82,015.50

54

CHAPTER 8

MATERIAL SAFETY DATA SHEET

ADIPIC ACID

SECTION 1 – Chemical Product and Company

Identification

MSDS Name: ADIPIC ACID

Synonyms: Hexanedioic acid; 1,4-Butane Dicarboxylic Acid

CAS#: 124-04-9

Formula: HOOC(CH2)4COOH

Molecular Wt: 146.1412

SECTION 2 – Hazards Identification

Potential Acute Health Effects: Hazardous in case of skin contact (irritant), of

eye contact (irritant), of ingestion, of inhalation.

Potential Chronic Health Effects:

Slightly hazardous in case of inhalation (lung sensitizer).

CARCINOGENIC EFFECTS: Not available.

MUTAGENIC EFFECTS:Not available.

TERATOGENIC EFFECTS: Not available.

DEVELOPMENTAL TOXICITY: Not available.

The substance may be toxic to the nervous system, gastrointestinal tract. Repeated

or prolonged exposure to the substance can produce target organs damage.

55

SECTION 3 – First Aid Measures

Eye Contact: Check for and remove any contact lenses. In case of contact,

immediately flush eyes with plenty of water for at least 15 minutes. Cold water

may be used. Get medical attention.

Skin Contact:

In case of contact, immediately flush skin with plenty of water. Cover the irritated

skin with an emollient. Remove contaminated clothing and shoes. Cold water may

be used. Wash clothing before reuse. Thoroughly clean shoes before reuse. Get

medical attention.

Serious Skin Contact:

Wash with a disinfectant soap and cover the contaminated skin with an anti-

bacterial cream. Seek medical attention.

Inhalation:

If inhaled, remove to fresh air. If not breathing, give artificial respiration. If

breathing is difficult, give oxygen. Get medical attention.

Serious Inhalation: Not available.

Ingestion: Do NOT induce vomiting unless directed to do so by medical

personnel. Never give anything by mouth to an unconscious person. Loosen tight

clothing such as a collar, tie, belt or waistband. Get medical attention if symptoms

appear.

Serious Ingestion: Not available.

SECTION 4 – Fire Fighting Measures

Flammability of the Product: May be combustible at high temperature.

Auto-Ignition Temperature: 420°C (788°F).

56

Flash Points: CLOSED CUP: 196°C (384.8°F).

Flammable Limits: Not available.

Products of Combustion: These products are carbon oxides (CO, CO2).

Fire Hazards in Presence of Various Substances: Slightly flammable to

flammable in presence of heat. Non-flammable in presence of shocks.

Explosion Hazards in Presence of Various Substances:Risks of explosion of the

product in presence of mechanical impact: Not available. Slightly explosive in

presence of open flames and sparks, of heat.

Fire Fighting Media and Instructions:SMALL FIRE: Use DRY chemical

powder. LARGE FIRE: Use water spray, fog or foam. Do not use water jet.

Special Remarks on Fire Hazards: Not available.

Special Remarks on Explosion Hazards: Dust generation can form an explosive

mixture if dispersed in a sufficient quantity of air.

SECTION 5 – Accidental Release Measures

Small Spill:Use appropriate tools to put the spilled solid in a convenient waste

disposal container. Finish cleaning by spreading water on the contaminated surface

and dispose of according to local and regional authority requirements.

Large Spill:Use a shovel to put the material into a convenient waste disposal

container. Be careful that the product is not present at a concentration level above

TLV. Check TLV on the MSDS and with local authorities.

57

SECTION 6 – Handling and Storage

Precautions:Keep away from heat. Keep away from sources of ignition. Empty

containers pose a fire risk, evaporate the residue under a fume hood. Ground all

equipment containing material. Do not ingest. Do not breathe dust. Wear suitable

protective clothing. In case of insufficient ventilation, wear suitable respiratory

equipment. If ingested, seek medical advice immediately and show the container or

the label. Avoid contact with skin and eyes. Keep away from incompatibles such as

oxidizing agents.

Storage: Keep container tightly closed. Keep container in a cool, well-ventilated

area. Do not store above 25°C (77°F).

Section 7: Exposure Controls/Personal Protection

Engineering Controls:

Use process enclosures, local exhaust ventilation, or other engineering controls to

keep airborne levels below recommended exposure limits. If user operations

generate dust, fume or mist, use ventilation to keep exposure to airborne

contaminants below the exposure limit.

Personal Protection:Splash goggles. Lab coat. Dust respirator. Be sure to use an

approved/certified respirator or equivalent. Gloves.

Personal Protection in Case of a Large Spill:Splash goggles. Full suit. Dust

respirator. Boots. Gloves. A self contained breathing apparatus should be used to

avoid inhalation of the product. Suggested protective clothing might not be

sufficient; consult a specialist BEFORE handling this product.

Exposure Limits:TWA: 5 (mg/m3) from ACGIH (TLV) [United States]

Inhalation Consult local authorities for acceptable exposure limits.

58

Section 8: Physical and Chemical Properties

Physical state and appearance: Solid. (crystalline powder.)

Odor: Odorless.

Taste: Tart

Molecular Weight: 146.14 g/mole

Color: White.

pH (1% soln/water): Not available.

Boiling Point: 337.5°C (639.5°F)

Melting Point: 152°C (305.6°F)

Critical Temperature: Not available.

Specific Gravity: 1.36 (Water = 1)

Vapor Pressure: Not applicable.

Vapor Density: 5.04 (Air = 1)

Volatility: Not available.

Odor Threshold: Not available.

Water/Oil Dist. Coeff: The product is equally soluble in oil and water;

log(oil/water) = 0.1

Ionicity (in Water): Not available.

Dispersion Properties: See solubility in water, methanol, acetone.

59

Solubility:Easily soluble in methanol. Soluble in hot water, acetone. Partially

soluble in cold water. Insoluble in Acetic acid, Petroleum Benzin, Benzene,

Petroleum Ether. Slightly soluble in Cyclohexane. Freely soluble in Ethanol.

Section 9: Stability and Reactivity Data

Stability: The product is stable.

Instability Temperature: Not available.

Conditions of Instability: Excess heat, excess dust generation, ignition sources,

incompatible materials

Incompatibility with various substances: Reactive with oxidizing agents.

Corrosivity: Not available.

Special Remarks on Reactivity: Not available.

Special Remarks on Corrosivity: Aqueous solutions of Adipic acid are corrosive

Polymerization: Will not occur.

Section 10: Toxicological Information

Routes of Entry: Inhalation. Ingestion.

Toxicity to Animals: Acute oral toxicity (LD50): 1900 mg/kg [Mouse].

Chronic Effects on Humans: May cause damage to the following organs: the

nervous system, gastrointestinal tract.

Other Toxic Effects on Humans: Hazardous in case of skin contact (irritant), of

ingestion, of inhalation.

Special Remarks on Toxicity to Animals: Not available.

Special Remarks on Chronic Effects on Humans: Not available.

60

Special Remarks on other Toxic Effects on Humans:Acute Potential Health

Effects: May cause skin irritation. Eyes: May cause eye irritation. Inhalation:

Expected to be a low hazard for usual industrial handling. May cause respiratory

tract. Symptoms may include coughing, sneezing, and blood tinged mucous.

Ingestion: Expected to be a low ingestion hazard if small amounts (less than a

mouthful) are ingested.Ingestion of large amounts may cause gastrointestinal tract

irritation with hyper motility, and diarrhea. May also affect behavior(somnolence,

convulsions), and metabolism, and may cause hemorrhaging. Chronic Potential

Health Effects: Inhalation: Repeated or prolonged contact by inhalation may cause

asthma.

Section 11: Ecological Information

Eco toxicity: Not available.

BOD5 and COD: Not available.

Products of Biodegradation: Possibly hazardous short term degradation products

are not likely. However, long term degradation products may arise.

Toxicity of the Products of Biodegradation: The product itself and its products

of degradation are not toxic.

Special Remarks on the Products of Biodegradation: Not available.

Section 12: Disposal Considerations

Waste Disposal: Waste must be disposed of in accordance with federal, state and

local environmental control regulations.

61

CONCLUSIONS

From this project, we learnt a lot about plant set up. Most interesting part was

performing mass and energy balance on each equipment through out the plant. I t

was not only a knowledgeable experience but also challenged all that we have

learnt in chemical engineering. We learnt to calculate the amount of utilities

required at each stage.

We acquired a deep knowledge about the safety protocols for our compound.

REFERENCES

www.chemicalweekly.com

www.wikipedia.com

Physprops

Coulson and Richardson 4th

edition

Research paper by G. Hoffman on crystallization

Perry’s handbook

www.patentgenius.com

Finalreport10bch0053

Documents

product adipic acid

uses adipic acid

adipic acid derivatives

study of adipic acid

tpd of adipic acid

consumption of adipic

introductionadipic acid

important dicarboxylic