CAPE3000 DESIGN PROJECT, 2023-24
TECHNICAL BRIEF FOR GROUPS – CE2, CE4, CME1 & CME2
DESIGN A PLANT TO MANUFACTURE STYRENE MONOMER
1 Introduction
(Name to be decided by the Group) Organic Chemicals Ltd has manufacturing sites in the USA,
UK and mainland Europe for the production of liquid ethylbenzene to be sold on as an
intermediate chemical.
Market Research within the Company has indicated an opportunity for a new Company product,
styrene monomer. The demand for styrene monomer is rising due to the closure of several old
plants and the Board will decide at their meeting in May 2024 whether to build a full-scale
manufacturing unit. If the case for manufacture looks strong enough, they plan to start
construction of the plant by the end of 2024. The ethylbenzene (assume pure) is available on site
and the production capacity of the styrene monomer plant is given in Table 1. The styrene
monomer specification is also given in the table.
You, as a group of chemical engineers in the Process Technology Department of (Name)
Organic Chemicals Ltd, have been charged with recommending the manufacturing technology to
be used. In the first semester, you are required to review the process options and to submit a
reasoned report to the Board setting out your recommended process route.
1.1 Design Requirements
In addition to the requirement to maximise return on investment, the Board is particularly
concerned that:
1) the styrene monomer production process should be efficient in raw materials and energy
usage;
2) the process should have the prospect of future improvements and capacity, and so should be
the subject of a strong development activity within the industrial community;
3) the technical understanding of the process should be such that the process can be run in a
predictable and reliable way. The Board is particularly concerned that the technical,
commercial and environmental risks are clearly stated;
4) provision must be made for safe storage and handling of all materials involved in the process;
5) the plant should meet all current and readily foreseeable safety, health and environmental
legislation.
Table 1: Project specifications
Group
Styrene plant
capacity
(Mte per annum)
Styrene monomer shall conform to the following requirements
Purity,
minimum
(wt%)
Ethylbenzene,
maximum
(mg/kg)
Benzene,
maximum
(mg/kg)
Polymer,
maximum
(mg/kg)
Inhibitor,
(mg/kg)
CE2 70,000
99.8 500 1 10 10 CE4 110,000
CME1 145,000
CME2 180,000
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1.2 Commercial factors
Further details of the commercial constraints around the design will be provided later but as a
guide, (Name) Organic Chemicals Ltd would normally seek to obtain an internal rate of return
(IRR) of more than 10% on its investments.
Detailed design and costing of the chosen technology will be carried out in Semester 2. It is
possible that manufacturing styrene monomer turns out not to be economically viable, in which
case (Name) Organic Chemicals Ltd will not proceed with building the plant.
Estimated prices of relevant raw materials and services are shown in Appendix 1.
1.3 Site data
The chosen location in the USA, UK or mainland Europe for the new plants to manufacture
styrene monomer is a green field area on a large, existing (Name) Organic Chemicals Ltd site.
The available site fronts directly onto the water and is surrounded by a mixture of houses,
schools and light/heavy industrial units on its landward boundaries.
The site has readily available services as listed in Appendix 1.
You can assume that the site has good marine discharge and loading facilities, that it has easy
access to rail services, the motorway network and is close to an airport.
1.4 Environmental considerations
The design should meet current Environment Agency guidance on emission levels.
All liquid or solid waste with a potential for contaminating the environment should be incinerated
at an external site. Any mixed organic/aqueous phases must be separated on site prior to shipping
of hazardous waste. You must therefore consider waste treatment as part of this project. Within
permitted limits, aqueous waste will be discharged by sewer to the local water treatment works.
The local authority sets disposal charges, details of which are set out in Appendix 1.
1.5 Material Availability
The materials and services which might be of interest to your task are set out in Appendix 1.
2 Roles
The Board is keen that there is clarity regarding the roles of the various participants in this study
and would remind you of the following points:
2.1 Supervisor & Technical Consultants
For details on the roles of the supervisor and the consultants and the consultancy arrangement,
see the Module Briefing document.
2.2 Group Members
As group members, you are responsible for the technical content of each activity and there should
be clarity regarding the roles of the various participants in this study.
The role of the supervisors/consultants is advisory. While advice is given in good faith, the
students must make a judgement as to its value.
You have the freedom to consider any process route, within the constraints set out in preceding
paragraphs and using any of the raw materials and services set out in Appendix 1. The process
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investigation and selection should, as far as possible, be made using information already in the
public domain.
3 Process Outline
You have the freedom to consider any manufacturing route, within the constraints set out in
preceding paragraphs and using services set out in Appendix 1.
The Board of Directors is very keen to avoid its competitors becoming aware of its plans at this
early stage. Accordingly, the process investigation and selection should, as far as possible, be
made using information already in the public domain.
The Board requires you to indicate clearly the sources of your data and, where data do not exist,
the nature of any assumptions made.
4 Reference
The following may be of some use to start the literature search:
Kirk-Othmer, Encyclopaedia of Chemical Technology, 3rd Edition, vol. 1, 179-191, John
Wiley, 1976.
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Appendix 1
The following services are available on site:
Service Specification Cost
Electrical power 11 kV 3 phase AC,
415 V 3 phase AC,
215 V, single phase AC
￡ 330 / MWh
￡ 350 / MWh
￡ 370 / MWh
Mains water for
process use
20oC (max), 6 bar supply pressure ￡ 1.0 / m3
Compressed air 7 bar ￡ 0.5 / 100 Nm3
N2 7 bar ￡ 10 / 100 Nm3
Cooling Water 4 bar supply pressure
Summer temperature = 23 C,
Maximum allowable return temperature = 40 C
￡ 6.5 / 1000 m3
(assuming all is
returned to the
cooling tower)
Chilled water 4 bar
Supply temperature = 10oC,
Maximum allowable return temperature = 20oC
￡ 25 / 1000 m
3
HP Steam
IP Steam
LP Steam
42 bar (dry, saturated)
15 bar (dry, saturated)
7 bar (dry, saturated)
￡ 4.5 / GJ
￡ 3.8 / GJ
￡ 3.2 / GJ
“Waste” Steam 2 bar (dry, saturated) ￡ 1.2 / GJ
Natural Gas 7 bar ￡ 30 / GJ
Costing calculations are to be based on the above UK Sterling Pound prices.
The following materials may be assumed to be available in sufficient quantity:
Material Specification Cost (￡/ actual tonne delivered)
Ethylbenzene 100% pure, liquid ￡ 180 / te
You may assume the following selling prices ex works:
Material Specification required Value
Benzene 99.5% w/w ￡ 150 / te
Toluene 99.5% w/w ￡ 160/ te
Styrene 99.8% w/w ￡ 210/ te
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Waste disposal charges are as follows:
Type of Waste Specification Cost of disposal
Solids for landfill Non-toxic waste, compacted
including non-contaminated
packaging
￡ 50 / te
Organic solvents for incineration Non-halogenated, high calorific value ￡ 30 / te
Organic solvents for incineration Non-halogenated, medium calorific
value (ca. 50/50 solvent/water)
￡ 120 / te
Organic solvents for incineration Non-halogenated, low calorific value
(mainly water)
￡ 180 / te
Organic solvents for incineration Halogenated or toxic, active
contaminated
￡ 350 / te
High purity waste streams No actives contamination, sent for
recovery to external contractor
Cost neutral
Aqueous waste Non-contaminated,
pH 6 – 9,
COD < 1kg/m3
Use Mogden
formula
Recyclable material Cardboard, paper, plastics,
compacted & bailed on site
Cost neutral
Toxic solid waste for incineration Includes contaminated packaging,
fibre board drums, protective
clothing, filter elements etc
￡ 500 / te
Average annual staff costs are ￡45 000 for each trained operator or maintenance personnel and
￡70 000 for managerial and professional staff.
Existing site medical, fire and security services are likely to be sufficient to service the new
plants. The styrene plant will be charged for these services dependent on its plot area, at the rate
of ￡17 / m
2 / year.
The following climatic conditions at the site are to be obtained by the group from local data:
Maximum dry bulb temperature
Minimum dry bulb temperature
Maximum annual rainfall
Maximum hourly rainfall
Maximum wind speed (1 in 100 year storm)
Prevailing wind direction
Maximum river temperature
Minimum river temperature
Maximum river discharge temperature
