Manufacturing of Ethylbenzene

Manufacturing of Ethylbenzene

CHAPTER 1 INTRODUCTION Ethylbenzene, also known as phenyl ethane and ethylbenzol, C6H5CH2CH3, is a single ring, alkyl aromatic compound. It is almost exclusively (> 90%) used as an intermediate for the manufacture of styrene monomer, C6H5CH=CH2, one of the most important large-volume chemicals. Styrene production, which uses Ethylbenzene as a starting raw material, consumes ca. 50% of the world’s benzene production. Less than 1% of the Ethylbenzene produced is used as paint solvent or as an intermediate for the production of Diethylbenzene and acetophenone.[9] 1.1 HISTORY OF DEVLOPMENT: Currently, almost all Ethylbenzene is produced commercially by alkylating benzene with ethylene, primarily via two routes: in the liquid phase with aluminium chloride catalyst, the vapour phase with a synthetic Zeolite catalyst developed by Mobil Corporation. The alkylation of aromatic hydrocarbons with olefins in the presence of aluminumchloride catalyst was first practiced by M .BALSHON in 1879. However, CHARLESFRIEDEL and JAMES M. CRAFTS pioneered much of the early research on alkylation and aluminium chloride catalysis. Over a century later, processes that employ the classic Friedel- Crafts reactions chemistry remain a dominant source of Ethylbenzene. In 1965 ca. 10% of the United States Ethylbenzene production was from the super fractionation of the mixed xylens stream produced by the catalytic reforming of naphtha. In 1986, the amount of Ethylbenzene derived from this source was insignificant because of the escalating cost of energy. Ethylbenzene was first produced on a commercial scale in the 1930’s by Dow Chemical in the United States and by BASF in the Federal Republic of Germany. The Ethylbenzene-styrene industry remained relatively insignificant until World War II. The tremendous demand for synthetic butadiene rubber (SBR) during the war prompted accelerated technology improvements and tremendous capacity expansion. This enormous war time effort led to the construction of several large scale factories, turning styrene production quickly into a giant industry. In 1986 the world annual production capacity of Ethylbenzene exceeded 14x106 tonnes, of which ca. 40% was produced in North America.[9]

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1.2 PROPERTIES: 1.2.1 Physical Properties: Under ordinary conditions, Ethylbenzene is a clear, colourless liquid with a characteristic aromatic odour. Ethylbenzene is an irritant to the skin and eyes and is moderately toxic by ingestion, inhalation, and skin adsorption. The physical properties of Ethylbenzene are as follows [9] Table 1.1: Physical properties of Ethylbenzene[9] Sr. No.

1

Properties

Density

At 150C

0.87139 g/cm3

At 200C

0.8669 g/cm3

At 250C

0.86262 g/cm3 -94.9490C

2

Melting Point

3

Boiling Point

At 101.3 KPa

136.1860C

4

Refractive Index

At 200C

1.49588

At 250C

1.49320

5

Critical Pressure

3609 KPa

6

Critical Temperature

344.020C

7

Flash Point

150C

8

Auto Ignition Temperature

4600C

9

Flammability Limit

10

11

12

Latent Heat

Heating Value

Surface tension

14

Specific Heat Capacity

1.0%

upper

-

fusion

86.3 J/gm

vapour ization

335 J/gm

gross

429999 J/gm

net

40928 J/gm 0

Kinematic viscosity

13

lower

At 37.8 C

0.6428x10-6 m2/s

At98.90C

0.390x10-6 m2/s 28.48 mN/m

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Ideal gas,250C

1169 J kg-1 K-1

Liquid,250C

1752 J kg-1 K-1

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1.2.2 Chemical Properties: The most important commercial reaction of Ethylbenzene is its dehydrogenation to styrene. The reaction is carried out at high temperature (600-6600C). Usually over an iron oxide catalyst. Steam is used as diluents. Commercially, selectivity’s to styrene range from 89 to 96% with per-pass conversions of 65-70%. Side reactions involve mainly the dealkylation of Ethylbenzene to benzene and toluene. Another reaction of commercial importance is the oxidation of Ethylbenzene by air to the hydro peroxide, C6H5CH(OOH)CH3 . The reaction takes place in the liquid phase, with no catalyst required. However, because hydro peroxides are unstable compounds, exposure to high temperature must be minimized to reduce the rate of decomposition. The production by products is reduced if the temperature is gradually lowered during the course of the reaction. The hydro peroxide is subsequently reacted with propene in a process that yields styrene and propylene oxide as co products. With suitable catalyst, Ethylbenzene can be converted to xylenes. Commercially processes for isomerising xylenes usually involve the catalytic isomerisation or dealkylkylation of Ethylbenzene. Like toluene, Ethylbenzene may be dealkylated catalytically or thermally to benzene. Ehtylbenzene also undergoes other reaction typical of alkyl aromatic compounds. [9] 1.3 USES: Essentially all commercial Ethylbenzene production is captively consumed for the manufacture of styrene monomer. Styrene is used in the production of polystyrene and a wide variety of other plastics (Styrene). Of the minor uses, the most significant is in the paint industry as a solvent, which accounts for <1% of production capacity. Even smaller volumes go toward the production of acetophenone, Diethylbenzene, and ethylanthraquinone.[9]

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CHAPTER 2 DIFFERENT MANUFACTURING PROCESSES There are different manufacturing processes available for Ethylbenzene .Some these are listed below: 1) Liquid phase aluminum chloride catalyst process 2) Vapour-phase zeolite catalyst process 3) Liquid phase zeolite catalyst process 4) Mixed Liquid-Vapour Phase zeolite Catalyst process

2.1 LIQUID PHASE ALUMINUM CHLORIDE CATALYST

PROCESS:[2,9] 2.1.1 Introduction: Liquid phase aluminum chloride processes have been the dominant source of Ethylbenzene since the 1930s to about 1980. Several companies have developed variations of this technology. Processes currently in use include those of Dow chemical, BASF, Shell chemical, Monsanto and union carbide/ badger. The Monsanto/Lummus technology is currently the most modern commercially licensed aluminium chloride alkylation technology. 2.1.2 Description: Alkylation of benzene with in the presence of an aluminum chloride catalyst complex is exothermic (ΔH=-114 kJ/mol). In the conventional AlCl3 process three phases are present in the reactor. Aromatic liquid, ethylene gas, and a liquid catalyst complex phase (a reddish brown material called red oil). A mixture of catalyst complex, dry benzene, and recycled polyalkylbenzenes is continuously fed to the reactor and agitated to disperse the catalyst complex phase in the aromatic phase. Ethylene and the catalyst promoter are injected into the reaction mixture through spargers, and essentially 100% of the ethylene is converted. Low ethylene: Benzene ratios are used to give optimum overall yield of Ethylbenzene. Commercial plants typically operate at ethylene: because molar ratios of ca.0.3-0.35. As the ratio is increased, more side reactions, such as transalkylation and isomeric rearrangement, occur. Further alkylation of Ethylbenzene leads to the reversible formation of lower Page 4

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molecular mass polyalkylbenzenes. The loss in net yield due to residue is minimized by recycling this material to the alkylation reactor. In addition, because the reaction occurs close to thermodynamic equilibrium, the traditional processes use a single reactor to alkylate benzene and transalkylate polyalkylbenzenes. The liquid reactor effluent is cooled and discharged into a settler, where the heavy catalyst phase is decanted from the organic liquid phase and recycled. The organic phase is washed with water and caustic to remove dissolved AlCl3 and promoter. The aqueous phase from these treatment steps in first neutralized and then recovered as a saturated aluminum chloride solution and wet aluminum hydroxide sludge. The unreacted benzene is recovered by the first columns as an overhead distillate. The second column separates the ethylbenzene product from the heavier polyalkylated components. The bottoms product of the second column is fed to a final column, where the recyclable polyalkylbenzenes are stripped from non recyclable high molecular mass residue compounds. The residue or flux oil, consisting primarily of polycyclic aromatics, is burned as fuel.

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2.1.3

Flow Sheet:

a : Reactor

d: EB Column

b: Flash Drum

e: PEB Column

c : Benzene Column

f : Drying Column

Fig 2.1: Liquid Phase Aluminum Chloride Catalyst Process

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2.2 VAPOUR -PHASE ZEOLITE CATALYST PROCESS:

[2,3,9]

2.2.1 Introduction: Vapour-phase alkylation has been practiced since the early 1940s, but at that time processes were unable to compete with liquid-phase aluminum chloride based technology. The alkar process developed by UOP, based on boron trifluoride catalyst, had modest success in the 1960s, but fell from favour because of high maintenance costs resulting from the severe corrosion caused by small quantities of water. Nevertheless, some Ethylbenzene units continue to use this process. The Mobil –badger Ethylbenzene process represents the latest and most successful vapour phase technology to be introduced. The process was developed in the 1970’s around. 2.2.2 Description: The reactor typically operates at 400-4500C and 2-3 MPa (20-30 bars). At this temperature >99% of the net process heat input and exothermic heat of reaction can be recovered as steam. The reaction section includes two parallel multibed reactors, a fired heater, and heat recovery equipment. The high-activity catalyst allows transalkylation and alkylation to occur simultaneously in a single reactor. Because the catalyst slowly deactivates as a result of coke formation and requires periodic regeneration, two reactors are included to allow uninterrupted production: one is on stream while the other is regenerated. Regeneration takes 36 hrs and is necessary after 6-8 weeks of operation. The catalyst is less sensitive to water, sulphur, and other poisons than the Lewis acid catalysts. The reactor effluent passes to the purification section as a hot vapour. This steam is used as the heat source for the first distillation column, which recovers the bulk of the unreacted benzene for recycle to the reactor. The remaining benzene is recovered from a second distillation column. The Ethylbenzene product is taken as the overhead product from the third column. The bottoms product from this column is sent to the last column, where the recyclable alkylbenzenes and polyalkylbenzenes are separated from heavy no recyclable residue.

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2.2.3

Flow Sheet :

a : Alkylation Reactor

d : EB Recovery Column

b : Secondary Reactor

e : PEB Recovery Column

c : Benzene Recovery

f : Stabilizer Column

Fig 2.2: Vapour-Phase Zeolite Catalyst Process

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2.3 LIQUID PHASE ZEOLITE CATALYST PROCESS:[2,3,9] 2.3.1 Introduction: The EBMax process offered by Mobil/badger is a liquid phase alkylation reaction using a catalyst based on the MCM-22. A commercial plant based on the EBMax technology was commissioned in 1955 at Chiba Styrene Monomer Company. 2.3.2 Description: A typical EBMax based plant flow diagram is shown below. The alkylation reactor is maintained in liquid phase and uses multiple bed catalyst beds ethylene injection. The ethylene conversion is essentially 100% in the alkylator reactors and the reactor nearly operates adiabatically. The exothermic heat of reaction is recovered and used to produce steams or as heat duty in the distillation columns. The transalkylator reactor in an EBMax plant can be either vapour phase or liquid phase. More recently, the transalkylation reactor has been designed as liquid phase because of its improved energy efficiency .The transalkylation reaction is conducted in the liquid phase using Mobil TRANS-4 catalyst. The alkylation and transalkylation reactor effluent stream are sent to the distillation section which consist of primarily of three distillation columns .The first column is a benzene column and it separates unconverted benzene into the overhead stream for recycle to the reactors. The benzene column bottom stream feeds the EB column. The EB column recovers the EB product in the overhead stream and the bottom stream of the EB column feeds the PEB column where PEB is fractionated overhead and recycle to the transalylation reactor. The bottom stream of the PEB column is removed as the residue stream and is generally used as fuel in an integrated styrene.

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2.3.3

Flow Sheet :

a : Benzene Column

b : EB Column

c : PEB Column

d : Vent Gas Column

Fig 2.3: Liquid Phase Zeolite Catalyst Process

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2.4 MIXED LIQUID-VAPOUR PHASE ZEOLITE CATALYST PROCESS:[12,3,9] 2.4.1 Introduction: The CDTECH process is based on mixed liquid-vapour phase alkylation reactor section. The design of commercial plant is similar to the liquid phase technologies except for the design of the alkylation reactor which combines catalytic reaction with distillation into a single operation. 2.4.2 Description: The CDTECH alkylation reactor consist of two main sections a catalytic distillation section and a Standard distillation section as shown in figure. Benzene is feed to the top of alkylation Reactor and Ethylene is fed as a vapour below the Catalytic Distillation Section creating a counter current flow of the Alkylation reactants through the catalytic distillation section throughout the catalytic distillation section a vapour liquid equilibrium is established is largely concentrated in the vapour phase. The Ethylene that dissolves into the liquid phase rapidly alkylates benzene on the catalyst active sites to produces EB. The rapid reaction of Ethylene in the liquid phase creates a driving force for additional Ethylene to dissolve into the liquid phase where the alkylation reaction occurs on the catalyst active site .The exothermic heat of reaction creates the vaporisation necessary to effect distillation the alkylation reaction product, mainly EB, Diethylbenzene and similar amounts of other by products are continuously fractioned and removed from the catalytic distillation section .in the lower section of alkylation reactor standard distillation occurs and the bottom stream contains primarily EB,PEB and other high boiling by-products.

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2.4.3 Flow Sheet:

a : Alkylator

e : EB Column

b : Finishing Reactor

f : PEB Column

c : Transalkylator

g : Light Column

d : Benzene Column

Fig 2.4: Mixed Liquid-Vapour Phase Zeolite Catalyst Process

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CHAPTER 3 PROCESS SELECTION Ethylbenzene is manufactured commercially by four processes as described in previous chapter.

3.1ADVANTAGES: 3.1.1

Liquid Phase Aluminum Chloride Catalyst Process: i.

The aluminium chloride present in alkylation reactor effluent catalyst transalkylation reaction.

ii.

Reaction is very fast in presence of Aluminum chloride &produces almost stoichiometric yields of Ethylbenzene.

iii.

Essentially 100% of ethylene is converted

3.1.2

Vapour Phase Zeolite Catalyst Process:

i.

Use of zeolite catalyst that eliminated issues associated with corrosion and waste disposal of aluminium chloride

ii.

The original vapour phase design accomplished the alkylation and transalkylation reactions in single reactor

iii.

The third generation technology is capable of achieving EB yield greater than 99%

iv.

The third generation technology offered significant benefits in purity ,capital cost

3.1.3 i.

Liquid Phase Zeolite Catalyst Process: The liquid phase zeolite catalyst process operates at substantially lower temperature decreased side reactions dramatically resulting in ultra high purity EB product

ii.

The plant achieve high on stream efficiency often greater than 99% which results in low turnaround & maintenance cost

iii.

EBZ-500 catalyst has operating length of more than 8year without catalyst regeneration

iv.

The regeneration is mild carbon burn procedure that is relatively inexpensive

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3.1.4

Mixed Liquid Vapour Phase Zeolite Catalyst Process:

i.

Combines catalyst reaction with distillation into single operation

ii.

The exothermic heat of reaction creates vapour isation necessary to effect distillation

iii.

Capable of using dilute ethylene feed e.g. Off gas from a fluid catalytic cracking plant or dilute ethylene from steam cracker

iv.

In general ethylene feed streams containing significant amounts of hydrogen, methane or ethane do not require some pre-treatment.

3.2 DISADVANTAGES: 3.2.1 Liquid Phase Aluminum Chloride Catalyst Process: i.

Handling and disposal of aluminium chloride catalyst and waste has become

increasingly

more

costly

and

complicated

because

of

environmental considerations ii.

Equipment and piping corrosion and fouling along with related environmental issues led to development of EB process based on solid acid heterogeneous catalysts

iii.

Major equipment pieces needed to replaced on regular schedule because of corrosion which results in extensive turnarounds poor plant on-stream efficiency and thus are primary contributors to the high operating costs associated with aluminium chloride

3.2.2

Vapour Phase Zeolite Catalyst Process: i.

The significant extent of isomerisation reactions and catalyst deactivation by deposition of carbonaceous material are most important problems associated with high temperature

ii.

The length of time between regeneration can vary from as little as 2 months to slightly more than 1 year depending on specific plant design and operating conditions

iii.

Because the reactors must be taken off line for regeneration ,on-stream efficiency can be low resulting in high operating costs for vapour phase plant

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iv.

Additional equipment may be required for regeneration procedure depending on specific plant design which adds capital cost to plant

Liquid phase zeolite catalyst process (EB-MAX) & Liquid-Vapour phase zeolite catalyst process (CDTech EB) both don’t have disadvantages. From above advantages & disadvantages for different processes we select Mixed Liquid-Vapour Phase Zeolite Catalyst process (CDTech EB). Since it has more advantages over other existing manufacturing process for Ethylbenzene. Also it requires less pure benzene & ethylene. Less harm full to environment also.

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CHAPTER 4 PROCESS DESCRPTION The “Mixed Liquid-Vapour Phase Zeolite Catalyst “process is selected for the manufacture of Ethylbenzene on following considerations: 1. 2. 3. 4.

Purity of product is more than other manufacturing process. Less pure ethylene & benzene is used. Low operating conditions. Cost of production is lower than other process.

4.1 MANUFACTURE:[9] Raw materials for the production of Ethylbenzene by Mixed Liquid-Vapour Phase Zeolite Catalyst process are: 1. Ethylene 2. Benzene

4.1.1

Ethylene: Ethylene is manufactured by following processes: 1. Pyrolysis of hydrocarbons (paraffins, preferably ethane). 2. Pyrolysis of naphtha & liquid feed stock 3. Ethanol dehydration 4. From coal

4.1.2

Benzene: Benzene is manufactured by following processes: 1. From coal 2. Form petroleum 3. Hydrodealkylation 4. Disproportionation

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4.2 PROCESS DESCRIPTION:[1,4] This process operates under alkylation reactor, which combines catalytic reaction with distillation into a single operation. Reaction temperature is 1500 C – 1950 C & operating pressure of, 1.6–2.1 MPa of pressure. The selectivity was above 83% (only benzene feed) and even higher than 99% (benzene plus transalkylation feed).

Fig 4.1 : Mixed Liquid-Vapour Phase Zeolite Catalyst Process

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A schematic flow diagram of mixed liquid-vapour phase zeolite catalyst process is shown in figure. The process can be conveniently split into 3 major sections 4.2.1 Alkylation section 4.2.2 Transalkylation section 4.2.3 Stripping and rectification section

4.2.1 Alkylation Reactions: The alkylation reactor consists of two sections catalytic distillation and standard distillation section. Benzene is fed at the top of the reactor and ethylene is fed as a vapour at the bottom in catalytic distillation section creating counter-current flow of reactants in the catalytic distillation section. In this section ethylene dissolves into the liquid phase rapidly heat of reaction creates the vapour isation necessary to effect the distillation. The alkylation products mainly ethylbenzene, di-ethylbenzene and other products are continuously fractioned and removed from the catalytic distillation section. In bottom section standard distillation occurs and bottom stream exits containing ethylbenzene, PEB and other products.

4.2.2 Transalkylation Reaction: Transalkylation reaction occurs on fixed beds of the catalyst using a vapour-liquid mixture of benzene and other impurities like cyclohexane. Transalkylation occurs at the temperature in the range of 220-250 0C. The benzene is used in stoichiometric excess which gives 50% conversion of PEB to ethylbenzene per pass.

4.2.3 Stripping And Rectification: PEB and ethylbenzene proceed to benzene stripping section which operates in the temperature range of 295-325 0C depending upon the pressure. Fired heater (or hot oil) provides heat for thermal duty. The stripping heat input also decreases the alkylation temperature thus improving the alkylation rate of reaction and minimizes the use of catalyst required

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CHAPTER 5 THERMODYNAMICS 5.1 THERMODYNAMICS :[1] The reactions involved in the manufacture of ethylbenzene are: 5.1.1 Alkylation: C6H6

+

Benzene

C2H4

C6H5CH2CH3

Ethylene

C6H5CH2CH3 Ethylbenzene

......................... (1)

Ethylbenzene

+ C2H4

Di-ethylbenzene .......................... (2)

Ethylene

5.1.2 Transalkylation: C6H4(CH2CH3)2 + C6H6

2 C6H5CH2CH3

Ethylbenzene

Ethylbenzene

Benzene

The main reaction is the alkylation of benzene to give ethylbenzene (Rx.-1). The above reaction is carried out at 1900 C in the presence of Zeolite Catalyst.

5.2 FEASIBILITY :[6,7,8] Before proceeding with any process, it is necessary to determine that under the given operating conditions the reaction is feasible. This can be determined by studying the free energy change of the process. The thermodynamic properties are collected as follows Table 5.1: Thermodynamic Properties Component

Δ S0 (J/mol.K)

Δ Hf0 (KJ/mol)

C6H5

269.20

82.93

C2H4

219.45

52.30

C6H5C2H5

360.45

29.79

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5.2.1 Heat Capacities Of Compounds, Cp Value in J/mol.K [8] Cp (C6H6)

= 155.6259 – 0.27105xT + 6.7508x10-4xT2

Cp (C2H4)

= 3.7977 + 0.1564xT – 8.3466x10-5xT2 + 1.7561x10-8xT3

Cp (C6H5C2H5)

= - 43.0868 + 0.7067xT - 4.8103x10-4xT2 + 1.3011x10-7xT3

5.2.2 Heat of Reaction:[5,7] Since the inlet temperature of reactants and outlet temperature of product are at different temperature we use the following formula for calculating Heat of Reaction at T=463K Δ HR(463K) = Δ Hf0 (EB) - Δ Hf0 (Benzene) - Δ Hf0 (Ethylene) + 298∫463 Cp(Product) dT – 353 298∫ CP (Benzene)

dT - λv (Benzene).......[Ref.7]

Where, Δ HR(463K)

= Heat of reaction at T= 463 K

Δ Hf0 (EB)

= Heat of Formation of Ethylbenzene at T=298 K

Δ Hf0 (Benzene) = Heat of Formation of Benzene at T=298 K Δ Hf0 (Ethylene) = Heat of Formation of Ethylene at T=298 K 463 Cp(Product) 298∫

dT = Sensible Heat of Ethylbenzene

353 298∫ CP(Benzene)

dT = Sensible Heat of Benzene up to its boiling point

λv (Benzene) = Latent heat of vapour isation of Benzene Δ HR(463K) = (29.66 – 82.83 – 52.29) x103 +298∫463 (- 43.0868 + 0.7067xT – 4.8103x10-4xT2 + 1.3011x10-7xT3 ) dT -

353 298∫ (155.6259

– 0.27105xT

+ 6.7508x10-4xT2 ) - 32.75x103 Δ HR(463K) = - 105.46x103 +26.8260x103 – 7650.1807 – 32.75x103 Δ HR(463K) = -119.0342x103 J/mol

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5.2.3 Entropy at Reaction Temperature (T=463 K):[6] For calculating entropy at T= 463 K, we use the following basic formula Δ S (463) = a ln (T2 /T1) + b (T2-T1) – c ( 1/T22 – 1/T12).........[Ref. 6] Where, T2 = Reaction Temperature T1 = Inlet Temperature a , b , c = Coefficients of Heat Capacity By using above formula we calculate the entropy of Ethylbenzene , Benzene , Ethylene as follows Δ SEB (463) = - 43.0868 ln (463 /298) + 0.7067 (463-298) – 4.8103x10-4 ( 1 /4632 – 1/2982) = 97.7686 J/mol.K Δ SB(463) = 155.6259 ln (463 /298) – 0.27105 (463-298) – 6.7508x10-4 ( 1 /4632 – 1/2982) = 23.8507 J/mol.K Δ SE(463) = 3.7977 ln (463 /298) + 0.1564 (463-298) +8.3466x10-5 ( 1 /4632 – 1/2982) = 27.479 J/mol.K Overall change in entropy is calculated as Δ S(463) = Δ SEB(463 - Δ SB(463) - Δ Se(463) = 97.7686 – 23.8507 – 27.479 Δ S(463) = 46.4389 J/mol.K

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5.2.4 Gibb’s Free Energy: Gibb’s Free Energy is calculated as, ΔG (463) = ΔHR (463) - TΔ S (463) = -119.0342x103 - 463x46.4389 ΔG (463) = - 140.5354x103 J/mol Since ΔG (463) ˂ 0, from thermodynamics considerations this reaction is more feasible.

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CHAPTER 6 MATERIAL BALANCE MATERIAL BALANCE: Material balance is the basis of process design. A material balance taken on complete process determines the quantities of material required and the products produced. Balance over individual process unit sets the process stream flows and compositions. Material balances are also useful tool for study of plant operation and trouble shooting. They can be used to check the performance against design to check instrument calibration and to locate the source of material loss

6.1 MATERIAL BALANCE ON REACTOR : 6.1.1 Assumptions :  No material losses are considered in any section of the process.  Pure ethylbenzene is obtained at ethylbenzene column.  All gases are assumed to behave ideally.  Final product (EB) obtained is of product specification.  100% conversion of ethylene to ethylbenzene & diethylbenzene only.  No formation of Polyethylbenzene. 6.1.2 Capacity: The capacity of the plant producing commercial grade ethylbenzene is 300000 ton/year =300*106 kg/year of Ethylbenzene. It has been assumed that plant operates 300 days per year and 24 hrs a day. BASIS : One day production of ethylbenzene = 300*106/300 = 1000 ton/day = 9433.962 Kmol/Day Chemical Reaction: C6H6 Benzene

+

CH2=CH2

→

Ethylene

C6H5CH2CH3 Ethylbenzene

1 Kmol Benzene = 1 Kmol ETHYLENE = 1 Kmol Ethylbenzene Page 23

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9433.962 Kmol Benzene = 9433.962 Kmol Ethylene = 9433.962 Kmol Ethylbenzene

Fig. 6.1 Material Balance on Alkylator Ethylene is limiting reactant & Ethylene conversion is 100% Therefore, Ethylene fed to alkylation = 9433.962 Kmol/day Excess reactant is Benzene, the ratio of Ethylene to Benzene be 1:4.682 Benzene fed to reactor = 9433.962*4.682=44169.81 Kmol/day Benzene evapour ated=44169.81-9433.962=34735.848 Kmol/day Assume 95% conversion in alkylator i.e. Reactor Heat evolved in reactor =0.95*9433.962*119.0342=1066815.914 J Benzene evapour ated=1066815.914/30.71= 34738.388 Kmol/day Total Production of Ethylbenzen is 9433.962 Kmol/day Page 24

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6.2 MATERIAL BALANCE ON TRANSALKYLATOR: Let x Kmol be from alkylator & 2y Kmol be from transalkylator x + 2y = 9433.962 Now, from reaction C6H4(CH2CH3)2 Di-Ethylbenzene

+

C6H6

2 C6H5CH2CH3

Benzene

Ethylbenzene

1 Kmol DEB = 1Kmol benzene = 2 Kmol EB y Kmol DEB= y Kmol benzene = 2y Kmol EB

Fig. 6.2 Material Balance on Transalkylator Selectivity =

83 =

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x = 83 y 83y +2y=9433.962 85y = 9433.962 y = 110.987 Kmol/day Kmol of DEB formed = 110.987 Kmol/day Kmols of EB formed from DEB = 2*110.987 = 221.97 Kmol/day Benzene consumed in transalkylator = 110.987 Kmol/day Ethylbenzene formed from alkylator = 9433.962 – 221.97 = 9211.992 Kmol/day In reactor 95% of Ethylbenzene is achieved EB formed in reactor =.95*9211.992=8751.3924 Kmol/day Benzene consumed in reactor = 8751.3924 Kmol/day In finishing reactor 5% of EB is achieved EB formed in reactor (b) = 0.5*9211.992 = 460.5996 Kmol/day Benzene consumed in reactor (b) = 460.5996 Kmol/day Benzene evapour ated = 44169.81 – 751.3924 – 60.5996 – 110.987 = 34846.891 Kmol/day

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6.3 MATERIAL BALANCE ACROSS BENZENE COLUMN:

Fig. 6.3 Material Balance on Benzene Column

6.4 MATERIAL BALANCE ACROSS ETHYLBENZENE COLUMN:

Fig 6.4 Material Balance on EB Column

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CHAPTER 7 ENERGY BALANCE ENERGY BALANCE: In the process design energy balances are made to determine the energy requirements of the processs: the heating, cooling and power required in the plant operation an energy audit on plant will show the pattern of energy usage and suggest the areas for energy conservation & solving.

7.1 GENERAL EQUATION FOR CONSERVATION OF ENERGY: Energy out = Energy in + generation – consumption - accumulation ....( Ref. 7) The process is considered as perfectly steady state and accumulation of both mass and energy will be zero.

7.2 ENERGY BALANCE ACROSS REACTOR: Steady state process assumption, Accumulation = 0 Input = Enthalpy of entering gases = HR Output = Enthalpy of exist gases = HP Therefore, Heat balance: Q = Heat out – Heat in + Heat of Reaction Q = HP – HR + ΔHr ....( Ref. 7) Reference temperature = 298 K Enthalpy of any component is given as ΔHi = ∫ = ni

463 298 ∫

(a + bT +cT2 + dT3) dT

= ni (a (463 - 298) + b/2 (4632 – 2982 ) + c/3 ( 4633 – 2983 )+d/4 (4634 – 2984))

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= ni (165*a + 62782.5*b + 24.2630*106*c + 9.5169*109*d )

Fig 7.1 Energy Balance On Alkylator HE

= ni (165*a + 62782.5*b + 24.2630*106*c + 9.5169*109*d) = 9433.962*103 (165*3.7977 + 62782.5*0.15649 – 24.2630*106*8.3466*10-5 + 9.5169*109* 1.7551*10-8 ) = 81.070*106 KJ

HB, IN = ni (165*a + 62782.5*b + 24.2630*106*c + 9.5169*109*d ) = 44169.81*103* (165*155.6259 – 62782.5* 0.27105 + 6.7508*10-4*24.2630*106) = 1.1060*109 KJ HB, OUT = ni (165*a + 62782.5*b + 24.2630*106*c + 9.5169*109*d) = 34735.848*103*25.0405*103 = 8.6980*108 KJ

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HEB = ni (165*a + 62782.5*b + 24.2630*106*c + 9.5169*109*d) = 9211.992*103*33390.98087 = 3.0759*108 KJ HDEB = ni (165*a + 62782.5*b + 24.2630*106*c + 9.5169*109*d) = 110.987*103*43691.1745 = 4.8491*106 KJ FOR ENTERING REACTANTS: HR = HE + HB,IN = 81.070*106 + 1.1060*109 = 1.18707*109 KJ FOR EFFLUENT: HP = HB, OUT + HEB + HDEB = 8.6980*108 + 3.0759*108 + 4.8491*106 = 1.1822*109 KJ ΔHR = -119.0342 KJ Therefore Q = HP – HR + ΔHR = 1.1822*109 - 1.18707*109 - 119.0342 = - 4.8701*106 KJ Therefore, Heat to be removed from the reactor by excess benzene.

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7.3 ENERGY BALANCE ON TRANSALKYLATOR: DEB= 110.987 Kmol, Benzene= 34957.818 Kmol, ETHYLBENZENE = 460.5996 Kmol

Fig. 7.2 Energy Balance on Transalkylator FOR REACTANTS: HDEB = 6.3763*106 KJ HB= 1.1636*109 KJ HR = 1.16997*109 KJ FOR EFFLUENT: HEB =9.7662*106 KJ HB = 1.1599*109 KJ HP = 1.16966*109 KJ Page 32

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Δ HR(508K) = Δ Hf0 (EB) - Δ Hf0 (Benzene) - Δ Hf0 (DEB) + 298∫508 Cp(EB) dT – 353 298∫ CP (Benzene)

dT - λv (Benzene)......(Ref.7)

= (29.66 + 22.41 – 82.83)*103 + 43.99*103 – 7.6501*103 - 30.75*103 = -25.1701 KJ/mol Q = HP – HR + ΔHr = 1.16966*109 - 1.16997*109 - 25.1701 = -310.025*103 KJ Therefore heat to be removed from transalkylator by using excess benzene.

7.4 ENERGY BALANCE FOR BENZENE COLUMN: F = 44391.779 Kmol D = 34846.83 Kmol W = 9544.949 Kmol

Fig 7.3 Energy Balance on Benzene Column Page 33

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(ASSUMPTION) L = 1.5*D L= 1.5* 34846.83 = 52270.245 Kmol V=L+D = 52270.245 + 34846.83 = 87117.075 Kmol The energy balance across distillation column is given by following equation: Fhf + Qr = Qc + Whw + Dhd Fhf = 966.707*106 KJ Whw= 135.442*106 KJ Dhd = 220.311*106 KJ Qc = V*λB = 87117.075* 30.75*103 = 2.6786*109 KJ Qr = Qc + Whw + Dhd - Fhf ....( Ref. 7 ) = 2.6786*109 + 135.442*106 + 220.311*106 - 966.707*106 = 2.0676*109 KJ

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7.5 ENERGY BALANCE FOR ETHYLBENZENE COLUMN: F = 9544.949 Kmol D = 9433.962 Kmol W = 110.987 Kmol

Fig 7.4 Energy Balance on EB Column (ASSUMPTION) L = 1.5*D L= 1.5* 9433.962 = 14.1509*103 Kmol V=L+D = 14.1509*103 + 9433.962 = 23.584*103 Kmol The energy balance across distillation column is given by following equation: Fhf + Qr = Qc + Whw + Dhd ....(Ref. 7) Fhf = 316.957*106 KJ Whw= 4.8818*106 KJ Page 35

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Dhd = 219.285*106 KJ Qc = V*λEB = 23.584*106* 35.56 = 8.3864*108 KJ Qr = Qc + Whw + Dhd - Fhf = 8.3864*108 + 4.8818*106 + 219.285*106 - 316.957*106 = 7.4584*108 KJ

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CHAPTER 8 DESIGN OF DISTILLATION COLUMN 8.1 NUMBER OF TRAYS : In design of distillation column, first we calculate the no. of stages required for desired separation of component of feed mixture. In our process, we want to separate benzene from ethylbenzene & diEthylbenzene. We get 99.5% benzene as overhead product & 0.5% as bottom product. (ASSUMPTION) Total feed =44,170 Kmol product

xd= 0 .995 , xw= 0.05 Assume our system is ideal system Therefore →α= P0A / P0B Where P0A= Vapour pressure of A at 463K P0B= Vapour Pressure of B at 463 K α = 3.44

.

Plot equilibrium curve using x-y data, use y= x

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

y

0

0.276

0.462

0.595

0.696

0.774

0.837

0.889

0.932

0.968

1

Assume two third of feed is vapour & one third liquid Minimum Reflux Ratio (Rm): Here q=

0.33

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Slope of feed line =

= -0.5

tan θ = - 0.5 θ = - 26.56 Intercept on Y-axis = From graph; x’ = 0.65 , y’ = 0.86 Minimum reflux ratio for feed partially vapour ised is given by, Rm =

’ ’

’

= 0.6428

Operating reflux ratio = 1.5*0.6428 = 0.9642 Operating line of rectification section: It is pass from (0.995, 0.995) on the diagonal & intercept on Y-axis =

= = 0.51

Operating line of striping section: It is pass from (0.005, 0.005) on the diagonal & the point of intersection of feed line & operating line of rectification section i.e. (0.68, 0.84) No. Of theoretical plates including reboiler = 11 (From Graph) No. Of theoretical plates required in the column = 10 Assume overall efficiency of trays = 60% Therefore actual no. of plates =

=

= 17 Page 39

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Line 1 : Rectifying Section Operating Line Line 2: Stripping Section Operating Line Line 3: Feed Line For Partially Vaporised Feed

Fig. 8.1 Graph of Number of Stages

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8.2 TOWER DIAMETER : (Ref. 10) The Principal factor that determines the tower diameter is the gas (vapour) velocity. It is the flooding condition that fixes the upper limit of gas (vapour) velocity. The flooding velocity is given by

vfl =

0.5

....(Ref. 10)

Where Vfl = flooding velocity of gas (vapour) K = constant ρl , ρv = density of liquid & vapour respectively Here,

= 42.55 Kg/ m3 ,

= 58 Kg/ m3

K=1

vfl = 0.6025 m/s Flooding velocity being known, the net area An is obtained as An

.... ( Ref. 10)

Maximum volumetric flow rate = 0.937 m3/s Flooding velocity = 0.6025 m/s An = 1.555 m2 Taking downcomer area as 12% of the total An = (100-12) % of At At = Dt = √

....(Ref. 10)

Dt = 1.5 m

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8.3 LIQUID FLOW PATTERN: (Ref. 10) Liquid flow pattern is determined by two parameters 1. Maximum liquid flow rate 2. Column diameter Here, Lmax = 0.195 + 2.355*10-3 = 0.1977 m3/s From fig. 8.2 we can say that the liquid flow pattern is single pass plate

Fig 8.2 Selection of Liquid Flow arrangement

8.4 PLATE DESIGN: (Ref. 10) Column diameter = 1.5 m Column cross section, At = 1.7671 m2 Take Downcomer Area 25% of Column cross section Page 42

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Downcomer Area, Ad = 0.25*1.7671 = 0.4417 m2 Net Area An= At - Ad = 1.7671 – 0.4417 =1.3254 m2 Active Area Aa= At – 2*Ad = 0.8837 m2 Assume hole area = 10% of Active Area Hole area = 0.10 * Active area = 0.10*0.8837 = 0.08837 m2 Weir length, lw = 0.77*Dt = 0.77*1.5 = 1.155m Weir Height: Since column operating at pressure above atmospheric pressure, hw = 50 mm Plate thickness = 5 mm 8.4.1

Cross Check (For Plate Dimension):

Maximum Liquid rate = 11.301 m3/s Assuming turndown ratio at 70% of maximum liquid flow rate, so that minimum liquid flow rate =

*11.301 =7.9107 m3/s

The height of liquid crest over the segmental weir:

(how)max = 0.75 (

)(2/3)

= 38 mm of clear liquid

(how)min = 0.75 (

)(2/3)

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= 30.7 mm of clear liquid At minimum flow rate, dh hw + (how)min = 50 + 30.7 = 80.7 mm

Fig. 8.3 Weep Point Correlation from fig 8.3 , Kw = 30.75 Therefore minimum vapour velocity, vmin =

vmin =

√

√

(

) (

)

= 6.3326 m/s But actual vapour velocity = = = 7.3982 m/s

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Thus the minimum operating velocity (7.3982 m/s) lies well above the weep point (i.e. when vapour velocity = 6.3326 m/s) Therefore our design is safe from operating point of view 8.4.2 Plate Pressure Drop:( Ref. 10) The total plate pressure drop is given by, ht = hd + hl + hr Dry plate drop hd = K1+ K2 (Vgh)2 ( ) For sieve plate, K1=0, K2= (58.85*10-3) / Cv2 Discharge coefficient Cv is determined as follows,

Fig. 8.4 Discharge coefficient for gas flow through sieve plates Page 45

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From fig. 8.4, Cv= 0.849 Velocity through holes Vgh = hd = 50.85*10-3 (

) (

)

= 34.73 mm of clear liquid Pressure drop due to static liquid head, hl = hw + (how)max = 50+38 = 88 mm of clear liquid Residual head, hr =

=

= 14.41 mm of clear liquid

The total pressure drop ht = hd + hl + hr = 34.73 + 88 + 14.41 = 137.74 mm of clear liquid 8.4.3 DOWNCOMER LIQUID BACKUP: (Ref. 10) Backup in downcomer is given by, hd c= ht + hw + how + hda + hhg Head loss in the downcomer due to liquid flow under the downcomer apron : hda = 0.166*(

)

Now, Aap = hap*lw Page 46

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hap= height of lower edge of the apron above the tray = hw – 10 = 50 – 10 =40 mm lw = 1.1 m Aap = Area under the downcomer apron = 0.04 * 1.1 = 0.044 m2 Since Aap < Ad we take Ad as Am hda = 0.166 (

)2

= 15 mm of clear liquid hdc = 137.14 + 50 +38 + 15 = 240.15 mm of clear liquid Check: To avoid flooding: hdc < Now,

Since hdc < 0.275 m, so there will be no flooding at specified operating condition that means tray spacing is acceptable Residence Time:

τr = =

= 7 sec

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So the design is satisfactory.

8.5 SHELL THICKNESS: For thickness of shell of distillation column we required following data, 1. Design Pressure, P = 1.1 * operating pressure = 1.1 * 2.1 = 2.31 N/mm2 2. Permissible tensile stress, f = 95 N/mm2 ( MOC= CARBON STEEL) 3. Joint efficiency factor , J = 0.85 ( for shell) , J = 1 ( for head ) 4. Inner diameter, Di = 1.5 m 5. Corrosion allowance, C = 1.5 mm Shell thickness is given by, ts=

–

ts = ts = 24 mm

8.6 HEAD THICKNESS: For safety we use hemispherical head at top & bottom of distillation column. The head thickness is given by, th =

....(Ref. 11)

th =

....(Ref. 11)

th = 10 mm

8.7HEIGHT OF COLUMN: Total height = 16*500 + 2*500 + 1509 = 10.51 m Page 48

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CHAPTER 9 COST ESTIMATION 9.1 ESTIMATION OF CAPITAL INVESTMENT COST : Cost of Producing Ethylbenzene per annum in 1965 = $5.5*106 Chemical Plant Cost Index for the year 1965 = 76.2 Chemical Plant Cost Index for the year 2010 = 539.1 Therefore, Cost of plant in 2010 = cost in 1965 * = 5.5*106*(539.1/76.2) = Rs.1,75,10,13,780

Since ($1=Rs.45)

Therefore, fixed Capital Cost = FCC= Rs.1,75,10,13,780 Therefore, Total Capital Investment= TCI=Rs.2,18,87,67,225 9.1.1 Direct Costs:a) Purchase Equipment = 15% of FCC = 0.15*1751013780 = Rs.2,62,65,267 b) Installation = 25% of Purchase Equipment =Rs 65,66,317 c) Instrumentation(Installed) =8% of Purchase Equipment =Rs.21,01,222 d) Piping(Installed) =10% of Purchase Equipment =Rs.26,26,527 e) Electrical= 10% of Purchase Equipment = Rs.26,26,527 f) Building= 11% of Purchase Equipment = Rs.28,89,180 g) Service facilities & yard improvement = 40% of Purchase Equipment = Rs.1,05,06,107 h) Land = 2% of Fixed Capital Cost = Rs.3,50,20,276 Total Direct Cost = Rs.8,86,01,423 Page 49

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9.1.2 Indirect Costs:a) Engineering & Supervision = 5% of Direct Cost = Rs.44,30,071 b) Legal Expenses = 1% of FCC = Rs.17,510,138 c) Construction Expenses & Contractors Fee = 10% of FCC = Rs.17,51,01,378 d) Contingency = 5% of FCC = Rs.8,75,50,689 Total Indirect Cost = Rs. 28,45,92,276

9.2 TOTAL PRODUCT COST : Let Total Product Cost = x 9.2.1 Manufacturing Cost : 9.2.1.1 Direct Production Costs : a. Raw Materials = 10% of TPC = 0.1x b. Operating Labour = 10% of TPC = 0.1x c. Direct Supervisory & clerical labour = 10% of operating labour = 0.01x d. Utilities = 10% of TPC = 0.1x e. Maintenance& Repair = 2% of FCC = RS.35,01,900 f. Operating Supplies = 0.5%of FCC = RS.8,75,475 g. Laboratory Charges = 10% of O.L = 0.01x h. Patents & Royalties = 1%of TPC = 0.01x 9.2.1.2 Fixed Charges : a. Depreciation = RS. 8,75,50,689 b. Local Tax = 1% of FCC = RS.1,75,10,138 c. Insurance = 0.4 % of FCC = Rs. 70,04,055 d.

Plant Overhead = 5% of TPC = 0.05x

9.2.2 General Expense : a. Administrative cost = 3% of TPC = 0.03x b. Distribution & Marketing Cost = 3% of TPC = 0.03x c. Research And Development Cost: 5% of TPC = 0.05x Let Fixed charge = 5.61% of TPC 112064882 + 0.05x = 0.0561x x= Rs. 1.8371*1010

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9.3 BREAK EVEN ANALYSIS : Cost of Ethylbenzene per kg= (1.8371*1010 / 300*106) = Rs. 60 / kg Assuming a Profit margin of 8%, so selling price of the product = Rs.65 / Kg Gross annual earnings = Total Annual Sales – Total Annual Product Cost = 1.95*1010 – 1.8371*1010 = Rs. 1,12,90,00,000 Net Annual earnings = Gross annual earnings – Income Tax = 1,12,90,00,000 – (0.4*1,12,90,00,000) = Rs. 67,74,00,000 Payback Period = Rate of Return = (

= 3.23 years )

= 38.68 %

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CHAPTER 10 ENVIRONMENTAL AND HAZOP STUDY HEALYH AND SAFETY aspects of the personnel & equipment are important in the plant. The plant has a variety of compounds that are hazardous to personnel as well as environment . fire accidents , exposure to chemicals, explosions are some of the major hazards in the operation the plant . hence safety and environment is given a careful attention. General precautions against fire : 1. Fire fighting equipments such as CO2 extinguishers and foam extinguishers should be provided. 2. Electrical equipment in flammable area should be flame proof 3. Lighting conductors should be insulated 4. Welding should be prohibited in the operating plant area . hot work permits should be demanded for welding purposes 5. Smoking should be prohibited in plant area 6. All leaks in pipelines and elsewhere should be immediately reported and rectified 7. Plant should be kept free of accumulations of waste combustibles ,cotton waste, paper etc. To ensure adequate considerations of safety during all phases of company’s activities , it is essential to have a sound safety policy. The policy must include at least the following : Management’s concern towards safety and health of employees

I. II. III.

Acceptable level of operational risks and standards of industrial hygiene in plant. Delegation of responsibilities to ensure operational safety down the line up to supervisors and what is expected from employee at various levels.

IV.

Procedure for authorization to adopt process changes / alterations / modifications / diversifications etc.

V.

Standards of operating instructions, their updating and documentation Generally, the prime responsibility for plant safety is to be assigned to the line management. By doing so, overlapping of accountability is prevented. Safety department fits in a role of staff function by contributing its experience, knowledge and judgment to influence management’s decision on matters concerning safety. Page 52

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10.1 CHEMICAL HAZARDS: 1. Special care is needed when working with chemicals that are known to have hazardous properties. It is important to understand the hazard in each case and to take proper precaution. 2. With newly developed chemicals, there may be no toxicity or other hazard data available. It is safest policy to treat all substances as hazardous until they have been provided to be otherwise. 3. Work in a well-ventilated fume cupboard ;use safety screens;always wear protective clothing; use the appropriate type of gloves; wear eye protection 4. Known or suspected carcinogenic substances should only be used after consulation with senior laboratory management 5. Containers of hazardous substances normally carry warning signs on their labels

10.2 SPECIAL MEASURES TAKEN IN PLANT FOR SAFETY: The major hazard is from exposure to toxic chemicals. The chemicals in the plant that are hazardous to the health are carbon black feedstock, its vapours, hydrogen and carbon monoxide. Thus proper care of personal safety should be taken.

10.3 GENERAL GUIDLINES FOR SAFETY: 1. Respiratory Protection: If respiratory irritation is experienced, use of a NIOSH-approved, full face, airpurifying respirators for organic vapours is recommended. Suitable positive-pressure, selfcontained breathing apparatus should be used for longer-term exposure in emergency situations, such as spill clean-ups or in situations when the atmospheric level is unknown. 2. Face and Eye Protection: For normal operations, chemical goggles should be worn, along with hard hats. For situations in which the potential for exposure is greater, a face shield is also recommended.

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3. Safety Showers and Eyebaths: Safety showers and eyebaths should be provided. They should be located in the immediate work area and readily accessible to personnel. Both should be tested routinely and frequently to ensure proper operation

10.4 ENVIRONMENTAL CONSIDERATIONS : Waste Removal : The waste gases are sent to vacuum cleanup and incinerated. Thus, waste are removed.

10.5 INSTRUCTIONS FOR QUICK SHUT DOWN :  Stop pumps if running.  Close drains if open.  Stop hot water pumps.  Close the main process valve and cooling water valve.  Leave the plant building checking that nobody is left inside.

10.6 MATERIAL SAFETY DATA SHEETETHYLBENZENE (MSDS): 1. Chemical Product and Company Identification : Product Name : Ethylbenzene

Contact Information :

Catalog codes: SLE2044

Sciencelab.com inc.

CAS#: 100-414

14025 smith Rd.

RTECS: DA0700000

ouston, Texas-77396.

TSCA: TSCA 8(b) inventory: Ethylbenzene

US Sales: 1800-901-7247

Cl#: Not available.

International sales: 1281-441-4400

Synonym: Ethylbenzene, Ethylbenzol

Order Online: Sciencelab.com

Chemical Name: Ethylbenzene

CHEMTREC (24 HR Emergency Telephone), call: 1800-424-9300

Chemical Formula: C8H10 Page 54

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2. Composition and Information on Ingredients : Composition: Name

CAS#

% by Weight

Ethylbenzene

100-414

100

Toxicological Data on Ingredients : Ethylbenzene : ORAL (LD50);Acute : 3500 mg/Kg (Rat)

3. Hazard Identification : Potential Acute Health Effects: Hazardous in case of eye contact (irritant), of ingestion, of inhalation. Slightly hazardous in case of skin contact (irritant, permeator) Potential Chronic Health Effects : Slightly hazardous in case of skin contact (irritant, sensitizer). CARCINOGENIC EFFECTS: Classified 2B (Possible for human) by IARC. MUTAGENIC EFFECTS: Mutagenic for mammalian somatic cells. Mutagenic for bacteria and/or yeast. TERATOGENIC EFFECTS: Not available. DEVLOPMENTAL TOXICITY: Not available. The substance may be toxic to central nervous system (CNS) Repeated or prolonged exposure to the substance can produce target organs damage. Other Toxic Effects on Humans : Hazard in case of ingestion of inhalation. Slightly hazardous in case of skin contact ( irritant ) Special Remarks on Toxicity to Animals : Lethal Dose/Conc.50% Kill : LD50[Rabbit]- Route: Skin: Dose : 17800ui/Kg Lowest Published Lethal Dose/Conc.: LDL[Rat]-Rout : Inhalation ( vapour ); Dose: 4000ppm/4H Special Remarks on Chronic Effects on Humans : May cause adverse reproductive effects and birth defects (teratogenic) based on animal test data. Page 55

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May cause cancer based on animals data. IARC evidence for carcinogenetic in animals is sufficient. IARC evidence of carcinogenicity in humans inadequate. May affect genetic material (mutagenic). Special Remarks on other Toxic Effects on Humans: Acute Potential Health Effects : Skin: Can cause mild skin irritation. It can be absorbed through intact skin. Eyes: Contact with vapour or liquid can cause severs eye irritation depending on concentration. It may also cause conjunctivitis. At a vapour exposure level of 85 – 200 ppm, it is mildly and transiently irritating to the eyes; 1000 ppm cause further irritation and tearing; 2000 ppm results in immediate and severe irritation and tearing; 5000 ppm is intolerable (ACGIH, 1991; Clayton and Clayton, 1994). Standardize test for eye irritation using 500 mg resulted in severe irritation ( RTECS ) Inhalation: Exposure to high concentrations can cause nasal, mucous membrane and respiratory tract irritation and can also result in chest constriction and trouble breathing, respiratory failure and even death. It can also affect behaviour/Central Nervous System. The effective dose for CNS depression in experimental animals was 10,000 ppm (ACGIH, 1991). Symptoms of CNS depression include headache, nausea, weakness, dizziness, vertigo, irritability, fatigue, light headedness, sleepiness, tremor, loss of coordination, judgement and consciousness, coma and death. It can also cause pulmonary enema. Inhalation of 85 ppm can produce fatigue, insomnia, headache and mild irritation of the respiratory tract (Haley & Bemdt, 1987). Ingestion: Do not drink, pipette or siphon by mouth. May cause gastrointestinal/digestive tract irritation with Abdominal pain, nausea, omitting. Ethylbenzene is a pulmonary aspiration hazard. Pulmonary aspiration of even small amounts of the liquid may cause fatal pneumonities.

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4. First Aid Measures : Eye Contact: Check for and remove any contact lenses. In case of contact immediately flush eyes with water for at least 15 minute. Cold water may be used. Warm water must be used. Get medical attention. Skin contact: Wash with soap and water. Cover the irritated skin with an arridient. Get medical attention if irritation develops. Serious Skin Contact: Not available. Inhalation: If inhaled remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical attention. Serious inhalation: Evacuated the victim to a safe area as soon as possible. Loosen tight clothing such as a collar, tie, belt or waist band. If breathing is difficult, administer oxygen. If the victim is not breathing, perform mouth-to-mouth resuscitation. Warning: it may be hazardous to the person providing aid to give mouth-to-mouth resuscitation when the inhaled material is toxic, infectious or corrosive. Seek medical attention. Ingestion: Do not induce vomiting unless directed to do so by medical personnel. Never give anything to an unconscious person. Loosen tight clothing such as a collar, lie, belt or waistband. Get medical attention. If symptoms appear. Serious Ingestion: Not available.

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5. Fire and Explosion Data : Flammability of the Product: Flammable Auto-ignition temperature: 4320C Flash Points: CLOSED CUP: 150C (Tagliabue), Open Cup: 26.6670C (Cleveland) (CHRIS, 2001) CLOSED CUP: 210C (NFPA) Flammable Limits: LOWER: 0.8% -1.6%, UPPER: 6.7-7% Products of Combustion: These products are carbon Oxides (CO, CO2) Fire Hazards in Presence of Various Substances: Highly flammable in presence of open flames and spark, of heat Explosion Hazards in Presence of Various Substances: Risks of explosion of the product in presence of mechanical impact: Not available Risks of explosion of the product in presence of static discharge: Not available Slightly explosive in presence of heat. Fire Fighting Media and Instructions: Flammable liquid, soluble or dispersed in water. SMALL FIRE: Use DRY Chemical powder. LARGE FIRE: Use Alcohol foam, water spray or fog. Special Remarks on Fire Hazards: Vapour may travel considerable distance to source of ignition and flash back.Vapours may form Explosive mixture with air. When Heated to Decomposition it emits acrid smoke and irritating fumes. Special Remarks on Explosion on Hazards: Vapours may form explosive mixture in air.

6. Accidental Release Measures Small Spill: Absorb with an inert material and put the spilled material in an appropriate waste disposal. Flammable liquid Keep away from heat. Keep away from sources of ignition. Stop leak if without risk. Absorb with Dry earth, Sand or other non-combustible material. Do not touch spilled material. Prevent entry into sewers, basements or confined areas. Be careful that the product is not present at a concentration level above TLV. Page 58

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7. Handling & Storage Precaution: Keep away from heat. Keep away from sources of ignition. Ground all equipment containing material. Do not ingest. Do not breath gas// fumes / vapour s/ spray. Avoid contact with eyes. 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. Keep away from incompatibles such as oxidizing agencies. Storage: Store in a segregated and approved area. Keep container in cool, well ventilated area. Keep container tightly closed and sealed until ready for use. Avoid all possible sources of ignition (spark or flame). Sensitive to light store in light resistant containers

8. Transport information DOT classification: CLASS 3: Flammable liquid Identification: Ethylbenzene UNNA: 1175 PG: II Special Provisions for transport: Not available.

9. Stability & Reactivity Data : Stability: The product is Stable. In Stability Temperature: Not available. Conditions of Instability: Heat, ignition sources (flame, spark, static), incompatible materials, light Incompatibility with various substances: Reactive with oxidizing agents Corrosivity: Not considered to be corrosive for metals and glass. Special Remarks on Reactivity: Can react vigorously with oxidizing materials. Sensitive to light. Special Remarks on Corrosivity: Not available. Polymerization: will not occur.

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CHAPTER 11 PLANT LOCATION AND LAYOUT Before any site selection work begins the company should be organized for expansion planning in a way that depends on the size of the firm. A company may want to utilize a standing committee, a special project team or planning by one person. In any event the planning function must be clear cut responsibility of one individual.

11.1 SITE SELECTION FACTORS: 1. Markets 2. Work force 3. Unionization 4. Transportation 5. Energy 6. Business climate 7. Water and waste systems 8. Living conditions 9. Topography The basic aim of the site selector is to choose a location that maximizes income and minimizes cost compromises usually have to be made. No site is ever perfect, and it is the mission of the site selection team to weigh the alternatives and compromises on the best choice.

11.2 PLANT LAYOUT : Plant layout involves developing physical equipment for a processing facility. The development must effect a balance of equipment spacing and integration of specific systems related to facility as a whole. Some of the factors to be considered for designing the plant layout are: 1. Process 2. Economics 3. Client requirements 4. Operation 5. Erection and maintenance 6. Safety 7. Environment

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Expansion : In-line plant layouts are made in various arrangements which often are referred to by letter designation. Various configurations are formed based on the main artery of the process unit i.e. the pipe rack, which contains long process and the utility lines that connect distant equipment and product piping entering and leaving the plant. Space for instrument and electrical feeders is allocated in the pipe rack such that they are connected to the related equipment. This area is kept free of piping and its related supports. Generally an I shaped plot is used for small process and an H-shape plot for larger units. In developing the plant layout for a chemical plant, it is essential that the firm decisions are made early as to equipments arrangement. This eliminates changes, which cost man-hours as the job progresses through engineering and design. The distillation sections are based on a grade-level process plant layout configuration. The steam generation and power facilities are housed in a building. The basic arrangement follows the equipment spacing charts and clearance tables

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Fig. 11.1 Plant Layout

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Sr. No.

NAME

1

Security Office

2

Time Keeping Office

3

Parking

4

Administration Building

5

Canteen

6

Security Office

7

Record Office for trucks

8

Weigh Bridge

9

Main Plant

10

Future Expansion

11

Medical Facilities

12

Storage Tanks

13

Workshop

14

Rest Rooms

15

Fire Station

16

D.G. Plant

17

L.T. Supply

18

Cooling Towers

19

Boilers

20

ETP

21

Control Room

22

Green Trees

Table 11.1 Plant Layout Description

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CHAPTER 12 CONCLUSION The selection of process for the manufacturing of Ethylbenzene by Mixed liquid vapour phase zeolite catalyst process is studied and concluded that is economic one. It is a simple Process. Though the process is very simple care should be taken to avoid formation of polyethylbenzene.

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CHAPTER 13 REFERENCES 1. Navid Naderpour, “Petrochemical Production Process” – SBS Publisher & Distributors Pvt.Ltd. 2. “Petroleum Technology” - Wiley Critical Content, Vol.-2, pp 974-990. 3. Sun G Gyu Lee, “Encyclopaedia of Chemical Processing”- Taylor & Francis Publisher,Vol.-1 4. David Netzer, 1138 Hacienda Ct. , Los Angels, Calif. 90069. “Mixed Phase Ethylene Process for Manufacturing Ethylbenzene”- U.S. Patent, Patent no.-5,977,423, Date of patent: Nov, 2, 1999. 5. Shenglin Liu, Fucun Chen, Sujuan Xie, Peng Zeng, Xiyan Du and Longya Xu. “Highly selective ethylbenzene production through alkylation of dilute ethylene with gas phase-liquid phase benzene and transalkylation feed” - Journal of Natural Gas Chemistry Volume 18, Issue 1, March 2009, Pages 21-24 6. Y V C Rao, “ Chemical Engineering Thermodynamics”- Universities Press (India) private Limited 7. David M. Himmelblau, “Basic Principles and Calculations in Chemical Engineering”PEARSON Education ,Sixth edition 8. PERRY & CHILTON, “ Chemical Engineers Handbook” 9. Ullmman’s Encyclopaedia of Industrial Chemistry (1985), vol.12, pp-519-530. 10. P. Chattopadhyay, “UNIT OPERATIONS OF CHEMICAL ENGINEERING”Khanna Publishers, Vol.-2. 11. V V Mahajani & S B Umarji, “Joshi’s Process Equipment Design” ,MACMILLAN PUBLISHERS INDIA LTD., Fourth Edition. 12. Peters, M.S. and Timmerhaus, K. D., “Plant Design and economics for chemical engineers”, fourth edition, McGraw Hill, New York, 1995 13. Crowl D.Y, Louvar J.F. “Chemical Process Safety Fundamentals with Applications”, Prentice Hall, Englewood, 1990. Websites : 1. 2. 3. 4. 5.

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Manufacturing of Ethylbenzene

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