United Arab Emirates University College Of Engineering Chemical Engineering Department Graduation Pr

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United Arab Emirates UniversityCollege Of
EngineeringChemical Engineering
DepartmentGraduation Project II
Advisor Dr. Shaheen Al-Muhtaseb
Aisha Rashid 200002115 Alia Mohammed
199902239 Amani Ahmed 199903894 Sheikha Rashid
199902221
Second Semester 2004/2005
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Project Objectives
Project Activities
Main equipments design
Material selection
Safety and environmental Impact
HAZOP study
Economical feasibility study
Recommendations
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Designing a chemical plant for Chlorinated Poly
Vinyl Chloride (CPVC) production.
Applying chemical engineering principles
Investigating economics, environmental and safety
factors
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Phase I of the Project
Activity 1
Literature search
Properties
Applications
Demand
Processes
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Phase I of the Project
Process selection
Activity 2
Activity 3
Material Energy Balances
Activity 5
Preliminary Cost Estimation
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Second Semester Project Activities
Activity 1
Design and sizing of individual equipments
Activity 2
Material selection of individual equipment
Activity 3
Safety and Environmental Impact
Activity 4
Perform HAZOP studies on the plant
Activity 5
Economical feasibility study
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Selected Process
Feed Preparation
Chlorination Reaction
HCl Removal Section
Drying Section
Chlorine Preparation
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In the absorber Chlorine gas is dissolved in
the slurry
Absorber
Absorber Design Steps
1. Selection of equipment
Sparged Vessel
2. Calculating vessel diameter (D) and height )H)
Vessel Volume
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3. Sparger Design
Chlorine gas bubble diameter
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Calculating the vessel diameter and height
Vapor
Total Slurry Volume
Slurry
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Applying safety factor of 15 on the design V
(1.5) (2.055) 3.082m3
Volume p H D2/ 4 Assuming Height (H) 3
Diameter (D) D 1.094 m H 3D 3.28m
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Pressure inside the vessel Thickness of the
vessel
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Heat Exchanger Design

• It is an equipment used to transfer heat to and
  from process fluids.
• It is an essential part of most chemical
  processes.

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Selected Type of heat-Exchanger
Agitated vessel
Fouling Blockage of pipes
Heating Slurry
Types of Agitated vessels
Heating Tank with immersed Coil
Jacketed Vessel
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The agitated vessel was design to be a baffled
vessel with impeller
Baffle A flat vertical strips Propose of
baffle Have large top-to-bottom circulation
without vortexing
Propose of Impeller To have a uniform
temperature inside the vessel
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Design heating tank with immersed coil Heat
transfer area of the coil Volume of
tank Diameter (D) and height (H) of tank
Height (h) and Diameter (d) of the impeller
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Chlorination Reactor Design

• Tubular Plug Flow Reactor (PFR)
• Design Equation

Where V the volume of the
reactor,m3 FAo Flow rate of A component,
mol/m3 rA Rate of reaction, mol/m3.s x
conversion of reaction
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Chlorination Reactor Design

• The volume of the reactor.
• The length and the diameter.
• The Area of the reactor.
• The pressure drop.

The design of a PFR aims to calculate
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Chlorination Reactor Design
1) Calculating the Volume
Where V Reactor Volume, m3 Volumetric flow
rate,0.00083 m3/sec t residence time, 1800 sec
V 1.5 m3
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Chlorination Reactor Design
2) Calculating the Length (L) and the diameter (D)
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Chlorination Reactor Design
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Chlorination Reactor Design
3) Calculating the Area (m2)
Where q heat transfer rate 505,288.5 kJ/hr
(Calculated in GPI) U overall heat transfer
coefficient 500 W/m2.oC A heat transfer area,
m2 ?Tlm the algorithmic mean temperature
difference, the temperature driving force 19.5
oC
A 15 m2
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Chlorination Reactor Design
4) Calculating the pressure drop in the tube-side
where jf is the dimensionless friction factor
5.510-3 L' effective pipe length 7 m d the
diameter of the pipe 0.3 m ut velocity of
fluid inside the pipe 0.011 m/s ? density of
fluid 1053 kg/m3
?P 0.0066 Pa
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Chlorination Reactor Design
5) Determine the cooling water required
Where q heat transfer rate 505,288.5 kJ/hr m
cooling water mass flow rate, kg/hr Cp heat
capacity of water 4.2 kJ/kg.oC Tc,in inlet
temperature in the shell side 15 oC Tc,out
exit temperature from the shell side 45 oC
mcw 4,010 kg/hr
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Rotary Dryer Design
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Rotary Dryer Design
Rotary Dryer Design Steps

• Calculate the Volume
• Calculate the Area Diameter
• Calculate the number of flight
• Calculate the thickness of Dryer
• Determine the thickness of insulation
• Determine the power required to derive the dryer

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Rotary Dryer Design
1) Calculate the Volume
Where Qt Total energy transferred, Btu/hr. Ua
Volumetric heat transfer coefficient,
Btu/hr.ft2. C. ?Tm Log mean temperature
difference between hot gases and material,C. G
Air mass velocity, lbm/hr (ft2 of dryer cross
section). D Dryer diameter, ft. V Volume of
dryer, ft3.
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Rotary Dryer Design
2) Calculate the Area Diameter
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Rotary Dryer Design

• L/D 8 (the range between 4-10)

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Rotary Dryer Design
3) Calculate the number of flight

• Number of flights 3D
• 6.64 7
• 7 flights are required using lip angle of 45.
• Radial height 0.276 ft

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Rotary Dryer Design
4) Calculate the thickness of Dryer
e 1.34 mm
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Rotary Dryer Design
5) Determine the thickness of insulation

• Insulation material Rock wool (K 0.045
  W/m.K)
• Material of dryer mild steel (K 46.7 W/m.K)

Heat lose from the dryer 5 of Heat of the dryer
Thickness of insulation 2 mm
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Rotary Dryer Design
6) Determine the power required to derive the
dryer
BHP 0.53 kw
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By comparing the corrosion resistance and the
cost of each material
Stainless steel (most frequently used corrosion
resistant materials in chemical industry)
Austenitic stainless steel 304 Is the most
generally used stainless steel because
It minimizes the cost and provides the desired
corrosion resistance.
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Cl2 H2O HCl
Important parameter
Corrosion receptivity
Wet system
Chlorine , Water
Material used for liquid system with the risk of
acid solution present

• Different grades of Stainless steel

• Silicon iron

• Aluminum and it alloy

• Nickel iron chromium

By comparing the corrosion resistance and the
cost of each material
Stainless steel (austenitic 304 18, Cr 12, Ni
25, Mo types 6(
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Material selection of individual equipment
Wet basis
Dry basis

• Present of chlorine and water

• No water and chlorine in the system

• Risk of corrosion

• No corrosion risk

• Material used
• Stainless steel

• Material used Carbon steel

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• No industry can achieve success without a strong
  commitment to protect the health and safety of
  its employees and society

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Summary of safety considerations for the used
chemicals
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Toxic Chemicals

• 1) NaOH (Sodium Hydroxide)
• Strong alkali
• Exposure limits in air is 2 mg/m3
• Affect the body by inhalation or contact with
  eyes and skin.
• Inhalation may result in damage to the
  respiratory tract tissues.

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Toxic Chemicals

• 2) HCl (Hydrochloric acid)
• Very strong acid
• Exposure limits in air is 7 mg/m3
• Harmful if inhaled
• Exposure to vapor causes sever burns in skin and
  eye damage.

• 3) Cl2 (Chlorine)
• Not flammable
• Max. concentration in air should not exceed 1000
  mg/m3
• Highly toxic by inhalation
• Vapor Cl2 cause eye and lung injury

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Control the Toxic Chemicals
Cl2 Use Vacuum

• HCl NaOH
• Special Storage and handling
• Prevent any spills and pipe leak

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Hazard and Operability Studies
Guide words
More
No or Not
Less
As well as
Part of
Reverse
Other than
Deviations The changes from the designers
intention
Causes Reasons why? And how the deviations
occur.
Consequences and action The results of the
deviation and the actions must be done.
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Feed Preparation Section
Chlorination Section
Drying Section
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Product Centrifuge
90CPVC 10 H2O
99.9CPVC 0.1 H2O
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Product Centrifuge
Rotary Dryer
90CPVC 10 H2O
CV9
Intention-CPVC inlet to rotary dryer
Guide word No
Deviation Flow

• Causes
• Product centrifuge empty
• Pipe leakage

• Consequence actions
• No Feed to dryer
• Check Repair supplying product centrifuge and
  pipes.
• Emergency Interlock in dryer.

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Product Centrifuge
Rotary Dryer
90CPVC 10 H2O
CV9
Intention-CPVC inlet to rotary dryer
Guide word LESS
Deviation Flow

• Causes
• Supplying product centrifuge leakage
• Pipe leakage
• CV failure

• Consequence actions
• Effect on product specification
• Check Repair supplying product centrifuge and
  pipes.

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Product Centrifuge
Rotary Dryer
90CPVC 10 H2O
CV9
Intention-CPVC inlet to rotary dryer
Guide word MORE
Deviation Flow

• Causes
• Valve failure

• Consequence actions
• Over flow in product centrifuge
• Effect on product specification
• Affect the product quality
• Check Repair CV
• Emergency Interlock in the dryer

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Fuel Gas
CV 12
Pump 1
CV 10
Intention-CPVC outlet from rotary dryer
Guide word No
Deviation Flow

• Causes
• CV failure
• Pipe leakage
• Pump failure

• Consequence actions
• Effect on product specification
• Check Repair CV, pump and pipes
• Control the flow rate of fuel gas

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Fuel Gas
CV 12
Pump 1
CV 10
Intention-CPVC outlet from rotary dryer
Guide word Less
Deviation Flow

• Causes
• CV failure
• Pipe leakage
• Pump failure

• Consequence actions
• Effect on product specification
• Check Repair CV, pump and pipes
• Control the flow rate of fuel gas

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Fuel Gas
CV 12
Pump 1
CV 10
Intention-CPVC outlet from rotary dryer
Guide word More
Deviation Flow

• Causes
• Valve failure
• Pump failure

• Consequence actions
• Effect on product specification
• Check Repair CV, pump and pipes
• Control the flow rate of fuel gas

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Important of economical feasibility study
Analyzing the net cash flow of the project
Expenditure (inputs) Earnings (outputs)

• Cash needed to pay for
• - Research and development
• Plant design and construction
• Plant operation

Expenditure
Earnings
Good (CPVC) for sales
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Cost of the plant
Working capital cost
Fixed capital cost
1,378,215

• Variable operating cost Raw materials
• Utilities
• Shipping and packing.
• 2. Fixed operating cost Maintenance
• Operating labour
• Laboratory, supervision
• Plant overheads
• Capital charge
• Insurance
• Local taxes

Variable operating cost 455,859

• The design cost
• Equipment and installation
• All piping
• Instrumentation and control systems
• Building and structures auxiliary facilities such
  as utilities
• Land and civil engineering work

Fixed operating cost 1,015,603
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• Assuming that
• The plant will operate for 20 years
• 3 years to start up, the timing of investment
  will be as follows
• Years 1 Constructing costs
• Years 2 Constructing costs
• Year 3 working capital

An excel spread sheet was prepared to find the
net cash flow in each year. That spreadsheet
resulted represented by the cash flow diagram
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Project cash flow diagram
Cumulative net cash flow 25.82 million
Pay pack time 4.2 years
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Discounted cash flow rate of return was found by
using solver to be DCFRR 23.29
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• The main problem faced
• lack of information about
• The rate of the PVC chlorination reaction
• The required residence time for the agitated
  slurry heater.

It is recommended to have the results of this
project improved through research on the missing
information
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• Thanks for your attention
• Any questions??