· I

DESIGN OF A PLANT TO PRODUCE 20,000 TONNES PER ANNUM OF

ACRYLONITRILE

BY

CHUKWUMA OKORO

2004/18570EH

A THESIS SUBMITTED TO THE DEPARTMENT OF CHEMICAL ENGINEERING IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR

THE AWARD OF BACHELOR OF ENGINEERING (B.ENG.) DEGREE IN CHEMICAL ENGINEERING.

DEPARTMENT OF CHEMICAL ENGINEERING SCHOOL OF ENGINEERING AND ENGINEERING TECHNOLOGY FEDERAL UNIVERSITY OF

TECHNOLOGY, MINNA, NIGER

STATE, NIGERIA.

DECEMBER 2009.

DECLARATION

Chukwuma Okoro do solemnly declare that this research project work was

out by me as a result of my personal effort and all references consulted are dully

.......................... . ....... , .............. .

DATE

11

DEDICATION

This project is dedicated to almighty God who has made my sojourn to FUT

a success also to my beloved father Chief Sir Samuel Okoro and my mother, Lolo,

y Florence Okoro my uncles, Mr. George Okoro and Dr Cypril Okoro as well as my

Lolo Elizabeth Oparaugo, who have contributed morally, spiritually and financially

the successful Completion of my degree program.

1ll

'. I

CERTIFICATION

This is' to certify that this work "DESIGN OF A PiLANT TO PRODUCE 20,000

TONNES PER ANNUM OF ACRYLONITRILE" was carried out by Okoro

chukwllma of Chemical Engineering Department, School of Engineering and

Engineering Technology Minna. This is in partial fulfil:lment of the requirement for the

award of Bachelor degree in Chemical Engineering.

APPROVED BY:

Engr Uthman Habib

(Project supervisor)

ENGR. DR. J. O. OKAFOR

(Head of Department)

EXTERNAL EXAMINER

DATE

DATE

DATE

IV

ACKNOWLEDGEMENT

I hereby express my sincere gratitude to the almighty God who has been my

strength, provider and source of my inspiration. lam also grateful to him for his divine

favour and love towards my wellbeing as a student.

My heart felt appreciation goes to my able supervisor Engr. Habib for his

guidance and fatherly assistance during the course of this project work. My appreciation

also goes' to head of department, staff and students of chemical engineering department,

federal university of technology Minna. To my course mates, the storm is over. Thank

you so much

I am highly grateful to my beloved parent Chief Sir Samuel Okoro and my

mother, Lolo, Lady Florence Okoro for laying a good foundation and supporting me to

this stage of my life. And to my Uncles, ~ou are wonderful; I love you all. May the

almighty God reward you in Jesus name amJn?

Lastly, I thank all my group members; linu, Fatima, Saheed, Mustapha, Nathaniel,

Yvonne, Atinuke, W';'ah, Yusuf, Abdulrashlem, Okike and Temitope for their effort and

contributions towards the success of these p oject.

v

ABSTRACT

This project work was carried out to design a plant to produce 20,000

nne/annum of Acrylonitrile using propylene and ammonia as the raw material with

iSl11uthmolybdatc as catalyst: The detailed design work like the material ancl energy

was done with the aid of computer aicled design(CAD) software like HYSYS ancl

THCAD. The major units in the plant are; Fluidized bed Reactor, Absorber, and

istillation unit. The design of the major equipment undertaken is the reactor, having a

of 4.155 m and height of 5.006 m. safety control, environmental impact

plant location and site layout were also carried out. Standard Cost estimation

carried out using detailed factorial method and this gives the total capital investment

to be 198mjllion Naira needed to generate a net profit of 314million Naira within a

back period of approximately six( 6) years for a plant life of 15 years. And the pay

ack rate is 22.56 %. Hence, the project was concluded to be economically viable.

TABLE OF CONTENT

TI1'LE PAGE ................. : ............................................................................................ I

DECLARA TION ........ ; ................................................................................................ II

CERTIFICATION ...................................................................................................... III

DEDICATION ........................................................................................................... IV

ACKNOWLEDGEMENT ........................................................................................... V

ABSTRACT ............................................................................................................... VI

TABLE OF CONTENTS ............................................................................................ VII

CHAPTER ONE ............................................................ 1-2

1.0 INTRODUCTION

1.1 AIMS AND OBJECTIVES

1.2 METHODOLOGY AND SCOPE OF WORK

CHAPTER TWO ........................................................... 3-9

2.0 LITERATURE REVIEW

2.1 Uses and Consumption of Acrylonitrile

2.2 Sohio Production Processes

2.3 Detailed Description with Control Operation

CHAPTER THREE ................................................... ···1 0-63

3.0 MATERIAL BALANCE

CHAPTER FOUR ....................................................... 64-81

4.0 ENERGY BALANCE CALCULATION

CHAPTER FIVE ............................................................ 82

5.0 FLOW SHEET OF THE PROCESS

CHAPTER SIX ......................................................... 83-137

6.0 EQUIPMENT DESIGN

6.1 . Design of a Fluidized bed Reactor

6.2 Absorber Sizing

6.3 Acrylonitrile Recovery Column Design

6.4 Acetonitrile Recovery Column Design

6.5 Design of Light Column

6.6 Design of Product Column

CHAPTER SEVEN ..................................................... 13 8-142

7.0. EQUIPMENT OPTIMIZATION

7.1 Optimization of the Fluidized Bed Reactor

CHAPTER EIGHT ................................................... 143-155

8.0 SAFETY AND QUALITY CONTROL

8.1 Safety control

8.2 Quality Control measure

8.3 General Process Safety Managenement

CHAPTER NINE ...................................................... 156-167

9.0 PROCESS CONTROL AND INSTRUMENTATIO

CHAPTER TEN ....................................................... 168-171

10.0 ENVIRONMENTAL ACCEPTABILITY

CHAPTER ELEVEN ................................................. 172-174

11.0 START UP AND SHUT DOWN PROCEDURE

CHAPTER TWELVE: ............................................... 175-183

12.0 SITE FOR PLANT LOCATION

CHAPTER THIRTEEN ............................................... 184-195

13.0 COST ESTIMATION AND ECONOMIC ANALYSIS OF PLANT

CHAPTER FOURTEEN ........................................... 196-197

14.0 RECOMMENDATION TO THE INDUSTRIALIST

14.1 CONCLUSION

APPENDIX ............................................................... 198-204

REFERENCE ................................................................... 205

CHAPTER ONE 1.0 Introduction

Acrylonitrile is a volatile, flammable, colorless liquid with a characteristic odor used in the

production of acrylic and modacrylic fibers, resins and rubbers, nnd as a chemical intermediate.

1t is somewhat soluble in water nnd miscible with most organic solvents. Almost 99 % pure with

minor quantities of impurities and stabilizers. It is first synthesized in 1893 by Charles Maureu,

and did become important until 1930, when industry began using it in new applications such as

acrylic fibers for textiles and synthetic rubber. In the 1940s the utility of acrylonitrile was

abandoned, existing manufacturing methods were expensive, multistep process. They seemed

reserved for the world's largest and wealthiest principal manufacturers (union carbide, American

cyanamide ).

In the late 1950s, however, sohio's discovery led to the production of plentiful and

inexpensive acrylonitrile of high purity as a raw material and to dramatic growth ill the

thermoplastics, synthetic fiber, and food packaging industries. Sohio' s process is a single- step

direct method for manufacturing acrylonitrile from propylene, ammonia and air over a fluidized

bed catalyst.

Occurrence in air

The dispersion of acrylonitrile is closely related to wind patterns; the highest levels in the

ambient air were found close to plants, especially downwind and they rapidly declined with

distance. Dry deposition and wet deposition (by rainfall) are believed to playa negligible role.

The degradation processes of acrylonitrile in the air are primarily chemical; they result in the

formation of hydrocyanic acid in 50 % of the mass and (based upon measurement of reaction

rates between acrylonitrile and hydroxyl radicals at concentrations present in the air) are believed

to be mainly responsible for the half-time (9-32 hours) of acrylonitrile in ambient air. In the soil,

ncryJonitrile is degraded by microorganisms. Its half-time in water was found to be 5-7 days.

However, an accidental spillage of 91 000 litres of acrylonitrile from a tanker resulted in

contamination of the soil and groundwater for more than a year, despite a cleaning process

lasting 108 days after the accident.

Uses

1. Principally acrylonitrile is a monomer in the manufacture of synthetic polymers,

especially polyacrylonitrile which comprises acrylic fibers.

2. It is also a component of synthetic rubber used in the production of nylon.

3. Small amounts are used as fumigant.

4. It is a precursor in the industrial manufacture of acrylonitrile and acrylic acid.

1

Health Effects

Acrylonitrile is highly flammable and toxic. It undergoes explosive polymerization. The burning

material releases fumes of hydrogen cyanide and oxides of nitrogen. The International Agency

for Research on Cancer (IARC) concluded that there is inadequate evidence in humans for the

carcinogenicity of acrylonitrile, but classified it as a carcinogen (possibly carcinogenic).

Acrylonitrile increases cancer in high dose tests in male and female rats and mice.

1.1 Aim and Objectives

The purpose of this project is to design a plant to produce acrylonitrile from propylene and

ammonia using single-step sohio process with effective and minimum cost of catalyst preventing

environmental hazards

1.2 Methodology and scope of work

The design of the plant is a mathematical work which can be done with the aid of scientific

calculator but this is rather tasking. With advancements in technology, computer software

applications have developed in order to achieve efficiency with respect to time and accuracy.

For this design,MS

, 1.21 METHODOLOGY

The need for high accuracy and precision in this project given rise to the use of computer

software like the MatllCAD and Autacad. While MathCAD is used for carrying out

calculations, the Autocad is'used for drawing the flow diagrams.

2