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UNIVERSITY MALAYSIA SABAH
SCHOOL OF ENGINEERING & INFORMATION TECHNOLOGY
HK03 CHEMICAL ENGINEERING PROGRAMME
SEMESTER II, 2012 / 2013
KC41803 PETROLEUM PROCESSING
GROUP ASSIGNMENT TITLE:
UOP Q-MAX CUMENE PROCESS
GROUP MEMBERS:
KENNY THEN SOON HUNG (BK09110098)
LEE CHEE HOE (BK09110001)
DATE OF SUBMISSION:
29TH MAY 2013
LECTURER:
ASSOC. PROF. IR. OTHMAN BIN ABDUL HAMID
THE PROJECT: UOP Q-MAX CUMENE PRODUCTION PROCESS
KC41803 PETROLEUM PROCESSING: GROUP ASSIGNMENT
TABLE OF CONTENTS:
1.0 HISTORY ON PETROLEUM REFINING ..................................................... 1
1.1 The Malaysian Oil And Gas Industry: An Overview ......................................... 3
1.2 Flow Diagram of Typical Refinery ............................................................... 10
1.3 Introduction On Cumene ........................................................................... 12
1.4 Cumene Production ................................................................................... 15
1.5 Cumene Properties .................................................................................... 16
1.6 Cumene Process ........................................................................................ 19
1.8 Cumene Chemical Properties ...................................................................... 21
1.9 Uses Of Cumene ....................................................................................... 24
1.10 Description On Q-Max Process .................................................................. 25
2.0 REFINERY BALANCE ............................................................................. 27
2.1 Introduction .............................................................................................. 27
2.2 The Abu Dhabi Oil Refining Company (Takreer) .......................................... 28
2.3 Refinery Installations ................................................................................. 32
2.3.1 Refinery Units ..................................................................................... 33
2.3.2 Utilities, Off-sites, Terminal & ADR Technology ..................................... 36
2.4 Mass Balance Based 400,000 BPD of Middle East Heavy Crude ..................... 40
2.4.1 Mass Balance by Assumed Proportion of Refining Products is Double ...... 41
2.4.2 Mass Balance by Fraction Method ......................................................... 44
2.4.3 Mass Balance based on Total Production from while Middle East Countries
.................................................................................................................. 46
2.5 Conclusion ................................................................................................ 51
3.0 GROUP PROJECT ................................................................................... 53
3.1 Introduction To Cumene Production ........................................................... 53
3.1.1 Cumene Project Definition .................................................................... 53
3.1.2 Cumene Manufacturing Routes ............................................................. 55
3.1.3 General Overall Material Balance for Cumene Process ............................ 58
3.1.4 Physical Properties .............................................................................. 59
3.2 Cumene Process ........................................................................................ 60
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3.3.1 Technical Description ........................................................................... 61
3.2.1 Cumene Chemical Properties ................................................................ 62
3.3 Chemical Reaction Network ........................................................................ 64
3.4 Various Processes of Manufacture .............................................................. 67
3.4.1 UOP Cumene Process .......................................................................... 67
3.4.2 Badger Cumene Process ...................................................................... 71
3.4.3 MONSANTO LUMMUS CREST Cumene Process ................................... 74
3.4.4 CDTECH & ABB Lummus Global ............................................................ 75
3.4.5 Q-MAX Process .................................................................................... 82
3.5 Description On Q-Max Process ................................................................... 85
3.6 Description On Process Flow ...................................................................... 87
3.7 Process Chemistry Chemical Reactions........................................................ 89
3.7.1 Transalkylation Of DIPB ................................................................... 91
3.7.2 Side Reactions .................................................................................... 92
3.8 Process Flow Diagram (PFD) .................................................................. 94
3.9 Description ............................................................................................... 97
3.10 Cumene Plant Section .............................................................................. 98
3.10.1 Storage and pumping section ............................................................. 98
3.10.2 Preheating and vaporization section .................................................... 98
3.10.3 Reactor section ................................................................................. 99
3.10.4 Separation and purification section ..................................................... 99
3.11 Current Industrial Cumene Production Process: UOP Process ................... 100
3.12 UOP Process Description For Cumene Production .................................... 101
3.13 Description Of Process Units .................................................................. 103
3.13.1 V-201 Vaporizer ............................................................................... 104
3.13.2 R-201 Reactor ................................................................................. 104
3.13.3 S-201 Separator .............................................................................. 104
3.13.4 T-201 Distillation Tower No. 1 .......................................................... 104
3.13.5 T-202 Distillation Tower No. 2 .......................................................... 104
3.14 Description Of Process Streams .............................................................. 105
3.14.1 Stream 1 ......................................................................................... 105
3.14.2 Stream 2 ......................................................................................... 105
3.14.3 Stream 3 ......................................................................................... 105
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3.14.4 Stream 4 ......................................................................................... 105
3.14.5 Stream 5 ......................................................................................... 105
3.14.6 Stream 6 ......................................................................................... 105
3.14.7 Stream 7 ......................................................................................... 106
3.14.8 Stream 8 ......................................................................................... 106
3.14.9 Stream 9 ......................................................................................... 106
3.14.10 Stream 10 ..................................................................................... 106
3.15 Reaction Mechanism And Kinetics Of Cumene Production ......................... 107
4.0 CAPACITY CALCULATION ................................................................... 108
4.1 Mass Balance .......................................................................................... 108
4.1.1 Introduction to Mass Balance ............................................................. 108
4.1.2 Material Balance of Major Equipment - Reactor ................................... 111
4.1.3 Material Balance of Propane Column ................................................... 117
4.1.4 Material Balance of Minor Equipment - Benzene Column ...................... 118
4.1.5 Material Balance of Minor Equipment Cumene Column ...................... 121
4.2 Heat Balance .......................................................................................... 124
4.2.1 Introduction to Heat Balance .............................................................. 124
4.2.2 Heat Balance for Major Equipment - Reactor ....................................... 128
4.2.3 Heat Balance for Propane Column ...................................................... 138
4.2.4 Heat Balance for Minor Equipment - Benzene Column .......................... 144
4.2.5 Heat Balance for Minor Equipment - Cumene Column ......................... 149
4.2.6 Product Yield ..................................................................................... 154
4.3 Flow Summary for Cumene Production at Design Conditions ...................... 157
4.4 Flow Summary for Utility Streams ............................................................ 160
4.4 Equipment Summary with Capacity for Cumene Producition Process ........... 161
5.0 BEHAVIOUR OF CATALYSTS/SOLVENTS............................................. 164
5.1 Feedstock Considerations ........................................................................ 164
5.1.1 Impact Of Feedstock Contaminants On Cumene Purity ..................... 164
5.1.2 Impact of Catalyst Poisons On Catalyst Performance ........................ 168
5.2 Process Performance ............................................................................... 170
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5.3 Production Of Cumene Using Zeolite Catalysts .......................................... 172
5.3.1 Unocals technology is based on a conventional fixed-bed system ......... 172
5.3.2 The second zeolite process, which was developed by CR&L ................. 172
5.4 Disadvantages Of Using Solid Phosphoric Acid (SPA) Process ..................... 173
5.5 Disadvantages of Using Aluminum Chloride As Catalyst ............................. 173
5.6 Catalysts in Cumene Production Process ................................................... 174
5.7 Catalysts And Reactions ........................................................................... 176
5.8 Cumene Process And Catalysts ................................................................. 179
5.8.1 SPA Catalyst...................................................................................... 180
5.8.2 AlCl3 and Hydrogen Chloride Catalyst .................................................. 181
5.8.3 Zeolite Catalysts ................................................................................ 182
5.9 Future Technology Trends ....................................................................... 194
5.9.1 Catalysts. .......................................................................................... 194
6.0 PROCESS AND INSTRUMENTATION DIAGRAM .................................. 196
6.1 Introduction To P&ID .............................................................................. 196
6.2 P&ID Diagram ......................................................................................... 197
6.2.1 Symbols and layout ........................................................................... 198
6.2.2 List Of Pid Items ................................................................................ 199
6.2.3 Basic symbols.................................................................................... 200
6.3 Introduction to Valve ............................................................................... 204
6.3.1 Type of Valve .................................................................................... 207
6.3.2 Multi-Turn Valve ................................................................................ 208
6.3.3 Quarter-Turn Valve ............................................................................ 221
6.4 Introduction to Safety Valve and Relief Valve ............................................ 239
6.5 Relief Concepts ....................................................................................... 241
6.6 Location of Reliefs ................................................................................... 241
6.7 Relief Types ............................................................................................ 243
6.7.1 Spring-Operated Valves ...................................................................... 244
6.7.2 Balanced-Bellows ............................................................................... 244
6.7.3 Rupture Discs ................................................................................... 245
6.8 P&ID for Reactor (Major Equipment) ........................................................ 248
6.8.1 P&ID for Reactor (Major Equipment) ................................................... 248
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6.8.2 Justification of The Control System Applied to the Reactor (Major) ....... 249
6.8.3 Justification of the Selection of the Type of Valve and Safety Valve to the
Reactor (Major Equipment) ................................................................ 250
6.9 P&ID For Cumene Column (Minor Equipment) ........................................... 253
6.9.1 P&ID For Cumene Column (Minor Equipment) ..................................... 253
6.9.2 Justification Of The Control System Applied To The Cumene Column .... 254
6.9.3 Justification Of The Selection Of The Type Of Valve And Safety Valve To
The Cumene Column (Minor) ............................................................ 255
7.0 HAZOP ANALYSIS ............................................................................... 258
7.1 HAZOP Analysis For Major Equipment - Reactor ........................................ 258
7.1.1 Recommendation HAZOP For Reactor ................................................. 271
7.2 HAZOP Analysis For Minor Equipment - Cumene Column ........................... 272
7.2.1 Recommendation HAZOP For Cumene Column .................................... 285
8.0 EXPLOSION ANALYSIS ....................................................................... 286
8.1 Introduction to Fire and explosions ........................................................... 286
8.2 Distinction Between Fires And Explosions .................................................. 287
8.3 Mechanism Of Fire And Explosion ............................................................. 288
8.4 Fire Triangle ........................................................................................... 289
8.5 Sources And Causes Of Fire And Explosion In Cumene Plant ...................... 291
8.5.1 Sources Of Fuel ................................................................................. 291
8.5.2 Sources Of Ignition ............................................................................ 292
8.5.3 Sources of Oxygen ......................................................................... 294
8.6 How To Identify Potential Fire And Explosion Sources ................................ 295
8.6.1 Fuel-Hydrocarbon Sources: Identifying And Documenting Hazards ....... 298
8.6.2 Oxygen Sources: Identifying And Documenting Hazards ...................... 300
8.6.3 Energy-Ignition Sources: Identifying And Documenting Hazards ........... 301
8.7 Reasons Why It Is Not Possible To Eliminate All Sources In Fire Triangle .... 304
8.8 Factors Affecting Ignitability Of Flammable Mixtures .................................. 307
8.9 Type Of Explosion Normally Happened In Cumene Plant ............................ 309
8.10 Fire And Explosion Analysis For Major Equipments ................................... 310
8.10.1 Fire And Explosion Analysis For Reactor ............................................ 312
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8.10.2 Fire And Explosion Analysis For Cumene Column ............................... 313
8.11 Identify Flammable Inventories And Locations In Cumene Plant ............. 314
8.11.1 Flammable Inventory: Propylene ...................................................... 314
8.11.2 Flammable Inventory: Benzene ........................................................ 316
8.11.3 Flammable Inventory: Di-Isoproply Benzene ..................................... 317
8.11.4 Flammable Inventory: Cumene ......................................................... 318
8.11.5 Flammable Inventory: Propane ......................................................... 319
8.12 Consequence Of Fire And Explosion Events ............................................. 320
8.13 Fire And Explosion Prevention And Control .............................................. 321
8.13.2 Minimization of Potential Amount Of Fuel .......................................... 322
8.13.2 Minimization Of Potential Sources Of Ignition .................................... 323
8.14 Additional Control Measures ................................................................... 325
8.15 Dust Control .......................................................................................... 326
8.16 Ignition Control ..................................................................................... 327
8.17 Damage Control .................................................................................... 328
8.18 Training Of Employees ........................................................................... 329
8.19 Management team ................................................................................ 329
9.0 ENVIRONMENT ANALYSIS .................................................................. 330
9.1 Introduction ............................................................................................ 330
9.2 Analytical Methods .................................................................................. 332
9.3 Emission Sources Of Cumene ................................................................... 333
9.3.1 Anthropogenic Sources ...................................................................... 335
9.4 Environmental Transport, Distribution, And Transformation ....................... 336
9.4.1 Cumene In Atmosphere ..................................................................... 336
9.4.2 Cumene In Water .............................................................................. 337
9.4.3 Cumene In Soil ................................................................................. 339
9.5 Environmental Levels And Human Exposure .............................................. 341
9.5.1 Environmental Levels ......................................................................... 341
9.5.2 Human Exposure ............................................................................... 344
9.6 Comparative Kinetics And Metabolism In Laboratory Animals And Humans . 346
9.7 Effects On Humans, Animals And Vegetation ............................................. 349
9.7.1 Overview of Chemical Disposition ....................................................... 350
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9.7.2 Genotoxicity ...................................................................................... 352
9.7.3 Acute and Sub-Acute Effects .............................................................. 353
9.7.4 Sub-Chronic and Chronic Effects ......................................................... 358
9.7.5 Summary of Adverse Health Effects of Cumene Inhalation ................... 365
9.7.6 Effects on Vegetation......................................................................... 368
10.0 COMMERCIAL VALUE ........................................................................ 370
10.1 Cumene Market Survey .......................................................................... 370
10.1.1 Cumene Market Overview ................................................................ 370
10.1.1 Market Survey In Year 2010 (Price Report) ....................................... 371
10.1.2 Market Survey In Year 2011 (Price Report) ....................................... 372
10.1.3 Market Survey In Year 2012 (Price Report) ....................................... 373
10.2 Cost Estimation & Economics ................................................................. 375
10.2.1 Background & Objectives ................................................................. 375
10.2.2 Cost Evaluation ............................................................................... 375
10.2.3 Investment ..................................................................................... 377
10.2.4 Project Economic Evaluation ............................................................. 385
10.3 Cumene Commercial Value Report .......................................................... 389
10.3.1 US October cumene prices remain stable amid quiet trade ................. 389
10.3.2 US benzene and RGP markets are quiet ............................................ 390
10.4 Cumene Value Chain ............................................................................. 391
10.5 World Demand Of Cumene .................................................................... 393
10.6 Current Market Situation ........................................................................ 395
10.7 Cumene Market Outlook ........................................................................ 397
10.8 Petrochemicals: Global Markets .............................................................. 398
10.9 Feedstock Requirements ........................................................................ 399
10.10 Case Study .......................................................................................... 402
10.11 Commercial Experience ........................................................................ 404
11.0 CONCLUSION AND RECOMMENDATIONS ......................................... 405
REFERENCES
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1.0 HISTORY ON PETROLEUM REFINING
Prior to the 19th century, petroleum was known and utilized in various fashions
in Babylon, Egypt, China, Persia, Rome and Azerbaijan. However, the modern history
of the petroleum industry is said to have begun in 1846 when Abraham Gessner
of Nova Scotia, Canada discovered how to produce kerosene from coal. Shortly
thereafter, in 1854, Ignacy Lukasiewicz began producing kerosene from hand-dug oil
wells near the town of Krosno, now in Poland. The first large petroleum refinery was
built in Ploesti, Romania in 1856 using the abundant oil available in Romania.
In North America, the first oil well was drilled in 1858 by James Miller Williams
in Ontario, Canada. In the United States, the petroleum industry began in 1859
when Edwin Drake found oil near Titusville, Pennsylvania. The industry grew slowly
in the 1800s, primarily producing kerosene for oil lamps. In the early 1900's, the
introduction of the internal combustion engine and its use in automobiles created a
market for gasoline that was the impetus for fairly rapid growth of the petroleum
industry. The early finds of petroleum like those in Ontario and Pennsylvania were
soon outstripped by large oil "booms" in Oklahoma, Texas and California.
Prior to World War II in the early 1940s, most petroleum refineries in
theUnited States consisted simply of crude oil distillation units (often referred to as
atmospheric crude oil distillation units). Some refineries also had vacuum distillation
units as well as thermal cracking units such as visbreakers (viscosity breakers, units
to lower the viscosity of the oil). All of the many other refining processes discussed
below were developed during the war or within a few years after the war. They
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became commercially available within 5 to 10 years after the war ended and the
worldwide petroleum industry experienced very rapid growth. The driving force for
that growth in technology and in the number and size of refineries worldwide was
the growing demand for automotive gasoline and aircraft fuel.
In the United States, for various complex economic reasons, the construction
of new refineries came to a virtual stop in about the 1980's. However, many of the
existing refineries in the United States have revamped many of their units and/or
constructed add-on units in order to: increase their crude oil processing capacity,
increase the octane rating of their product gasoline, lower the sulfur content of their
diesel fuel and home heating fuels to comply with environmental regulations and
comply with environmental air pollution and water pollution requirements.
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1.1 The Malaysian Oil And Gas Industry: An Overview
The Oil & Gas (O&G) industry has seen no small amount of attention during recent
months. One item attracting attention is crude prices rising above USD50 per barrel
(0.159m3) and the simultaneous rise of petrol prices due to reduction in government
subsidies.
News of discoveries of new potentially producing fields has increased interest
in O&G related stocks, whether in suppliers to the industry or oil refineries. To
encourage and maintain this level of interest, IEM held a symposium in July 2004,
attempting to put forward a forum where people outside the O&G industry could be
exposed to issues within the industry.
Petroleum exploration in Malaysia started at the beginning of the 20th century
in Sarawak, where oil was first discovered in 1909 and first produced in 1910. Prior
to 1975, petroleum concessions were granted by state governments, where oil
companies have exclusive rights to explore and produce resources.
The companies then paid royalties and taxes to the government. This state of
affairs ceased on April 1, 1975 as a result of the Petroleum Development Act,
whereby PETRONAS became the custodian of petroleum resources with rights to
explore and produce resources. The national oil company retains ownership and
management control in exploration, development and production of oil resources.
Expenditure and profits are managed under instruments called Production Sharing
Contracts (PSCs). The Production Sharing Contractor assumes all risks and sources
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all funds for all petroleum operations. The Contractor receives an entitlement
through production.
Figure 1.1 Production Sharing Contractor Entitlement
Each PSC may have different terms and conditions. For example, different
time periods are allowed for exploration of acreage, developing and installing
infrastructure to produce any hydrocarbons discovered, and the actual production
period.
Malaysia has the 25th largest oil reserves and the 14th largest gas reserves in
the world. The total reserves is of the order of 18.82 billion barrels oil equivalent
(boe), with a crude production rate of 600 thousand barrels per day.
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Figure 1.2 Historical Crude Oil Production (bbls : barrels per day. SB :
Sabah contribution. SK : Sarawak Contribution, PM : Peninsular
contribution.)
The average natural gas production stands at approximately 5.7 billion
standard cubic feet per day. Malaysia has 494,183km2 of acreage available for oil
and gas exploration, with 337,167 km2 in the offshore continental shelf area, and
63,968km2 in deepwater.
The acreage is split into 54 blocks, out of which 28 (a total of 205,500km2)
are currently operated by Petronas Carigali Sdn. Bhd. plus seven other multinational
oil companies.
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Figure 1.3 Historical Natural Gas Production
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Figure 1.4 Increased production through rejuvenation
There is also an opportunity to increase production by rejuvenation of existing
production facilities. This concept can be applied both to topside and subsurface
facilities. As an example, more than 50% of Malaysian assets have been producing
for longer than 15 years. There are definite opportunities to debottleneck facilities,
looking at design and current operating conditions, and maximising the use of
existing equipment. New technologies may be retrofitted into existing equipment,
increasing capacity at an acceptable cost.
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Figure 1.5 Competitiveness of the Industry
Although there are few lower cost centres in this region, the international
clients still prefer Malaysia due to its high quality engineering produced and
availability of up to date technology knowledge. The Oil and Gas industry can be
split into upstream and downstream sectors. The upstream sector includes the
exploration and the extraction of crude oil.
In the Malaysian Oil and Gas sector, it has been the upstream sector that has
traditionally been developed. The Petroleum Development Act 1974 governs the
upstream and the downstream sectors of the petroleum industry under which
Petronas is party of. Petronas has a licensing system. All work which is contracted
out in the upstream sector is through licensed contractors. One of the objectives of
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the Act was to make sure local players were involved. One of the requirements to
obtain a licence is being a local company. It is because of this that the oil and gas
engineering industry was fully developed by the mid 80s. From the mid 80s to late
80s, all engineering design work had to be done locally.
According to Ir. Dr Torkil Ganendra, Secretary of MOGEC and Director of Aker
Kvaerner Asia Pacific, the Oil and Gas industry in Malaysia is a regulated industry,
thus all upstream engineering works have to be performed locally if there was local
technical capability. Some specialised areas are done overseas.
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1.2 Flow Diagram of Typical Refinery
The image below is a schematic flow diagram of a typical oil refinery that depicts the
various unit processes and the flow of intermediate product streams that occurs
between the inlet crude oil feedstock and the final end products.
The diagram depicts only one of the literally hundreds of different oil refinery
configurations. The diagram also does not include any of the usual refinery facilities
providing utilities such as steam, cooling water, and electric power as well as storage
tanks for crude oil feedstock and for intermediate products and end products.
There are many process configurations other than that depicted above. For
example, the vacuum distillation unit may also produce fractions that can be refined
into end products such as: spindle oil used in the textile industry, light machinery oil,
motor oil, and various waxes.
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Figure 1.6 Schematic Flow Diagram of typical oil refinery
(Source: http://en.wikipedia.org/wiki/Oil_refinery)
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1.3 Introduction On Cumene
The cumene molecule can be visualized as a straight-chain propylene group
having a benzene ring attached at the middle carbon , C6H5CH(CH3)2 . It is a
colourless liquid , bp 152.40C having a characteristic aromatic odor . It is isomeric
with n-propylbenzene , ethyltoluene and trimethylbenzene.
Figure 1.7 Chemical Structure Of Cumene
(Source: http://en.wikipedia.org/wiki/Cumene)
Cumene is the common name for isopropylbenzene, an organic
compound that is an aromatichydrocarbon. It is a constituent of crude oil and
refined fuels. It is a flammable colorless liquid that has a boiling point of 152 C.
Nearly all the cumene that is produced as a pure compound on an industrial scale is
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converted to cumene hydroperoxide, which is an intermediate in the synthesis of
other industrially important chemicals, primarily phenol andacetone.
Thus cumene is also named as 1-methylethyl benzene or 2-phenyl-propane or
isopropylbenzene. Cumene (C9H12) is a substituted aromatic compound in the
benzene , toluene and ethylbenzene series.
Cumene is a clear liquid at ambient conditions. High purity cumene is
normally manufactured from propylene and benzene and is a minor constituent of
most gasolines. It is the principal chemical used in the world wide production of
phenol and its co-product acetone.
Many consumer or industrial products such as plywood and composition board
banded with phenolic resins, nylon-6, epoxy and polycarbonate resins and solvents,
have origins that can be traud to cumene.
Cumene processes were originally developed between 1939 and 1945 to meet
the demand for high octane aviation gasoline during world war-II. In 1989 about
95% of cumene demand was as an intermediate for the production of phenol and
acetone. A small percentage is used for the production of -Methylstyrene.
Before the devolopement of the cumene route to phenol and acetone,
cumene had been used extensively during warld war2. It is a curious fact that
although propylation of benzene by means of phosphoric acid and aluminium
chloride have been the standard methods of manufacture for many years ,the first
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plan used sulphuric acid as a catalyst. This was a war time expedient arising from
uncertainity over phosphoric acid supplies.
Almost all the worlds supply of cumene is now produced as an intermediate for
phenol and acetone manufacture. Some refinery units still produce cumene for use
as an antiknock constituent of gasoline but it is doubtful whether new plants would
be constructed for this purpose .
Neither does it seem likely that any large scale plant would be installed for
manufacturing the hydroperoxide, methylstyrene ,diisopropylebenzene,or
acetophenone ,although these cumene derived compounds are of considerable
commercial importance. They occur as byproducts during cumene and phenol
production, and are usually marketed by manufacturers .
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1.4 Cumene Production
Commercial production of cumene is by FriedelCrafts alkylation of
benzene with propylene. Previously, solid phosphoric acid (SPA) supported
on alumina was used as the catalyst. Since the mid-1990s, commercial production
has switched to zeolite-based catalysts.
Isopropyl benzene is stable, but may form peroxides in storage if in contact
with the air. It is important to test for the presence of peroxides before heating or
distilling. The chemical is also flammable and incompatible with strong oxidizing
agents. Environmental laboratories commonly test isopropyl benzene using a Gas
chromatographymass spectrometry (GCMS) instrument.
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1.5 Cumene Properties
Cumene
IUPAC name
(1-methylethyl)benzene
Other names
isopropylbenzene
2-phenylpropane
Identifiers
CAS number 98-82-8
PubChem 7406
ChemSpider 7128
UNII 8Q54S3XE7K
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KEGG C14396
ChEBI CHEBI:34656
RTECS number GR8575000
Jmol-3D images Image 1
Properties
Molecular formula C9H12
Molar mass 120.19 g mol1
Appearance colorless liquid
Density 0.862 g cm3, liquid
Melting point 96 C, 177 K, -141 F
Boiling point 152 C, 425 K, 306 F
Solubility in water Insoluble
Viscosity 0.777 cP at 21 C
Hazards
R-phrases R10,R37,R51/53,R65
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S-phrases S24,S37,S61,S62
Main hazards Flammable
Flash point 43 C
Related compounds
Related compounds ethylbenzene, toluene, benzene
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1.6 Cumene Process
The Cumene process (Cumene-phenol process, Hock process) is
an industrial process for developing phenol & acetone from benzene and propylene.
The term stems from cumene (isopropyl benzene), the intermediate material during
the process. It was invented by Heinrich Hock in 1944 and independently by R. dris
and P. Sergeyev in 1942 (USSR).
This process converts two relatively cheap starting
materials, benzene and propylene, into two more valuable ones, phenol and acetone.
Other reactants required are oxygen from air and small amounts of a radical initiator.
Most of the worldwide production of phenol and acetone is now based on this
method. In 2003, nearly 7 billion kg of phenol was produced by the Hock Process.
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1.7 Technical Description
Benzene and propylene are compressed together to a pressure of 30 standard
atmospheres at 250 C (482 F) in presence of a catalytic Lewis acid. Phosphoric
acid is often favored over aluminium halides. Cumene is formed in the gas-
phase Friedel-Crafts alkylation of benzene by propylene:
Cumene is oxidized in air which removes the tertiary benzylic hydrogen from
cumene and hence forms a cumene radical:
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1.8 Cumene Chemical Properties
Cumene is a colourless liquid, soluble in alcohol, carbon tetra chloride, ether and
benzene. It is insoluble in water. Cumene is oxidized in air which removes the
tertiary benzylic hydrogen from cumene and hence forms a cumene radical:
This cumene radical then bonds with an oxygen molecule to give
cumene hydroperoxide radical, which in turn forms cumene
hydroperoxide (C6H5C(CH3)2-O-O-H) by abstracting benzylic hydrogen from another
cumene molecule.
This latter cumene converts into cumene radical and feeds back into
subsequent chain formations of cumene hydroperoxides. A pressure of 5 atm is used
to ensure that the unstable peroxide is kept in liquid state.
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Cumene hydroperoxide is then hydrolysed in an acidic medium (the Hock
rearrangement) to givephenol and acetone. In the first step, the terminal
hydroperoxy oxygen atom is protonated.
This is followed by a step in which the phenyl group migrates from the benzyl
carbon to the adjacent oxygen and a water molecule is lost, producing
a resonance stabilized tertiary carbocation.
The concerted mechanism of this step is similar to the mechanisms of
the Baeyer-Villiger oxidationand also the oxidation step of hydroboration-
oxidation.[6] In 2009, an acidified bentonite clay was proven to be a more
economical catalyst than sulfuric acid as the acid medium.
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As shown below, the resulting carbocation is then attacked by water, a proton
is then transferred from the hydroxy oxygen to the ether oxygen, and finally the ion
falls apart into phenol and acetone.
The products are extracted by distillation.
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1.9 Uses Of Cumene
1. As feed back for the production of Phenol and its co-product acetone
2. The cumene oxidation process for phenol synthesis has been growing in
popularity since the 1960s and is prominent today. The first step of this
process is the formation of cumene hydroperoxide. The hydroperoxide is
then selectively cleaved to Phenol and acetone.
3. Phenol in its various formaldehyde resins to bond construction materials like
plywood and composition board (40% of the phenol produced) for the
bisphenol A employed in making epoxy resins and polycarbonate (30%) and
for caprolactum, the starting material for nylon-6 (20%). Minor amounts are
used for alkylphenols and pharmacuticals.
4. The largest use for acetone is in solvents although increasing amounts are
used to make bisphenol A and methylacrylate.
5. - Methylstyrene is produced in controlled quantities from the cleavage of
cumene hydroperoxide, or it can be made directly by the dehydrogenation
of cumene.
6. Cumene in minor amounts is used as a thinner for paints, enamels and
lacquers and to produce acetophenone, the chemical intermediate
dicumylperoxide and diiso propyl benzene.
7. Cumene is also used as a solvent for fats and raisins.
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1.10 Description On Q-Max Process
The most promising materials were modified to improve their selectivity and then
subjected to more-rigorous testing. By 1992, UOP had selected the most promising
catalyst based on beta-zeolite for cumene production and then began to optimize
the process design around this new catalyst. The result of this work is the Q-Max
process and the QZ- 2000 catalyst system.
1. Raw material propylene and benzene are used for the production of cumene.
2. These are stored in the respective storage tanks of 500MT capacity in the
storage yard pumped to the unit by the centrifugal pumps.
3. Benzene pumped to the feed vessel which mixes with the recycled benzene.
Benzenestream is pumped through the vaporizer with 25 atm pressure and
vaporized to the temperature of 243degC, mixed with the propylene which is
of same and temperature and pressure of benzene stream.
4. This reactant mixture passed through a fired super heater where reaction
temperature 350degC is obtained.
5. The vapor mixture is sent to the reactor tube side which is packed with the
solid phosphoric acid catalyst supported on the kieselguhr the exothermal
heat is removed by the pressurized water which is used for steam production
and the effluent from the reactor i.e., cumene, p-DIPB, unreacted benzene,
propylene and propane with temperature 350oC is used as the heating media
in the vaporizer which used for the benzene vaporizing and cooled to 40oC in
a water cooler, propylene and propane are separated from the liquid mixture
of cumene, p-DIPB, benzene in a separator operating slightly above atm and
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the pressure is controlled by the vapor control value of the separator, the fuel
gas is used as fuel for the furnace also.
6. The liquid mixture is sent to the benzene distillation column which operates at
1 atm pressure, 98.1% of benzene is obtained as the distillate and used as
recycle and the bottom liquid mixture is pumped at bubble point to the
cumene distillation column where distillate 99.9% cumene and bottom pure
p-DIPB is obtained.
7. The heat of bottom product p-DIPB is used for preheating the benzene
column feed, All the utility as cooling water, electricity, steam from the boiler,
pneumatic air are supplied from the utility section
8. The typical reactor effluent yield contains 94.8 Wt. % cumene and 3.1 Wt. %
of diiso propylbenzene. The remaining 2.1 % is primarily heavy aromatics.
9. This high yield of cumene is achieved without transalkylation of diiso
propylbenzene and is unique to the solid phosphoric acid catalyst process.
10. The cumene product is 99.9 Wt. % pure and the heavy aromatics, which have
an octane number of 109, can either be used as high octane gasoline
blending components or combined with additional benzene and sent to a
transalkylation section of the plant where diiso propylbenzene is converted to
cumene.
11. The overall yields of cumene for this process are typically 97-98 Wt. % with
transalkylation and 94-96 Wt. % without transalkylation.
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2.0 REFINERY BALANCE
2.1 Introduction
Changes such as structural and cyclical in our business environment have keep us on
our toes. Our core businesses are changing in our historic home of Europe. The
Consumption of both chemicals and petroleum products is down and new demands
for more diesel and less gasoline, greener products and so on which are taking shape
currently.
We are not surprise to any changes that come to us. Since we had foreseen
most of them and are now adjusting our production base accordingly, while deploying
all our innovation capabilities to create a line of products in sync with our customers
expectations.
In addition, we are setting the stage for our expansion in regions of strong
economic growth at the same time such as Asia, the Middle East and Africa, and
adapting to the specific needs of those markets, by leveraging solid partnerships and
the remarkable agility of all our activities.
Total (37.5%) and Saudi Aramco (62.5%) are partners in SATORP, the
company building the Jubail refinery in Saudi Arabia. This strategically important
project will allow us to move closer to oil and gas fields and consumers.
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2.2 The Abu Dhabi Oil Refining Company (Takreer)
Basically, The Abu Dhabi Oil Refining Company (Takreer) was established in 1999 in
order to take over the responsibility of refining operations previously undertaken by
the Abu Dhabi National Oil Company (ADNOC). There are several companys areas of
operation which include the refining of crude oil and condensate, supply of petroleum
products and production of granulated Sulphur in compliance with domestic and
international specifications. Moreover, this refinery can work for 85,000 bbl/day
capacity.
Figure 2.1: The PMC contract is for the EPC phase of the base oils plant in
Ruwais Industrial Complex.
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Today, The Shaw Group Inc. had announced that their company has been
awarded a contract by The Abu Dhabi Oil Refining Company (Takreer) to provide
project management consultancy services during the engineering, procurement and
construction phase of a base oils plant at the Ruwais Industrial Complex in Abu Dhabi.
Basically, the planned facility will be capable of producing 500,000 tons/year of
Group III base oils, as well as 100,000 tons/year of Group II base oils, and is scheduled
to begin commercial production in 2013. Group II and III base oils are used for
blending top-tier lubricants for car engines.
Besides, an announcement was made by UOP LLC, a Honeywell company, that
they have been selected by the Abu Dhabi Oil Refining Company, also known as
Takreer, with the aim to supply technology and engineering services for an expansion
at its Ruwais Refinery in the United Arab Emirates.
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The history of the refineries in Abu Dhabi Refinery which consists of
85000bbl/day is shown in Figure 2.2 below:
Figure 2.2: history of the refineries in Abu Dhabi Refinery which consists
of 85000bbl/day
1996Plant Expansion 85,000 BBL/day
1983New Refinery 60,000 BBL/day
1976Original Plant 15,000 BBL/day
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The history of the refineries in Ruwais Refinery which consists of 40000bbl/day
is shown in below:
Figure 2.3: History of the refineries in Ruwais Refinery which consists of
40000bbl/day
There are other facilities such as below:
Power Geeration 660MW
Water Desalination 14.0 MM Gallons/ day
Hazardous Material Treatment, 26MMT/Year
2006
Gasoline Units
2000
Condensate units 280,000 BBL/day
1985
Hydrocracker units
1981
Hydro-skimmer units 120,000BBL/day
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2.3 Refinery Installations
After the discovery of oil in Abu Dhabi in year 1958 and the first export shipments of
Crude in year 1962, there are a plans to build a glass root Refinery with a capacity of
15,000 barrels per stream day (BPSD) to meet a growing local need for petroleum
products. Basically, the construction work has begun in year 1973. This work cost
around initial $45 million and this plant was inaugurated in the April of 1976.
Therefore, we can see that the demand for oil products were grow rapidly.
However, the work began almost on installing a new Refinery to process a further
60,000 BPSD and this was commissioned in year 1983.
So, requirements has continued to grow in the fast-developing Emirate and
ADNOC has decided to expand the capacity yet again with environmental
considerations in mind and to include additional units for Gas Oil Desulphurization and
Sulphur recovery. Therefore, the expanded Refinery with a capacity rate of 85,000
BPSD has been started up in December 1992.
On the other hand, a Salt and Chlorine Plant has been commissioned at Umm
Al Nar in the year of 1981 which was merged with the Refinery in year 1990 in order
to form the Abu Dhabi Refinery and Chlorine Division.
On 30th November 2001, it was permanently shut down. Two power plants,
owned and operated by Umm Al Nar Power Company, and a Lube oil blending/filling
plant, owned and operated by ADNOC Distribution, are located adjacent to the
Refinery.
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The refinery is a Hydro Skimming Complex designed to process Bab Crude as
well as a mixture of Asab-Sahil, Shah and Thammama Condensate. Finished products
from the Refinery are as follows: Liquefied Petroleum Gases, Naphtha, Unleaded
Gasoline, Aviation Turbine Kerosene, Domestic Kerosene, Gas Oil, Straight Run
Residue, Liquid Sulphur.
2.3.1 Refinery Units
Therefore, the refinery unit including:
1. Crude Distillation Unit (85,000 BPSD)
2. Naphtha Hydrodesulphuriser Unit (22,795 BPSD)
3. Kerosene Merox Unit (21,250 BPSD)
4. Catalytic Reformer Unit (14,000 BPSD)
5. Gas Oil Hydrodesulphuriser Unit (22,500 BPSD)
6. LPG Treating and Recovery Unit (3,480 BPSD)
7. Excess Naphtha Stabilizer Unit (3,325 BPSD)
8. Gas Sweetening Unit (35 tons/day H2S Removal)
9. Sulphur Recovery Unit (35 tons/day)
10. Jarn Yaphour Crude Oil Stabilization Plant (10,000 BPSD)
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2.3.1.1 Crude Distillation Unit (85,000 BPSD)
For initial step, prior to the actual distillation process, Crude Oil is passed
through a Desalter Unit to remove the undesirable salts, water and sludge
which are generally associated with any type of crude.
After final heating in a furnace, the Crude is then fractionated in the
Atmospheric Distillation Column into the basic raw petroleum fractions of
Naphtha, kerosene, Gas Oil and Straight Run Residue.
2.3.1.2 Naphtha Hydrodesulphuriser Unit (22,795 BPSD)
The Naphtha Hydrodesulphuriser sweetens the Straight Run Naphtha from
Crude Unit.
This unit has produced three products namely: Heavy Naphtha, Light Naphtha
and Sour Liquefied Petroleum Gases.
2.3.1.3 Kerosene Merox Unit (21,250 BPSD)
Mercaptans was converted by the unit in the straight run kerosene into
disulphine in order to meet the final product quality for aviation kerosene.
2.3.1.4 Catalytic Reformer Unit (14,000 BPSD)
The Reformer processes the Heavy Naphtha cut to improve its anti-knock
properties prior to using it as a Gasoline blending component.
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2.3.1.5 Gas Oil Hydrodesulphuriser Unit (22,500 BPSD):
Gas oil sulphur content has been reduced by the Gas Oil Hydrodesulphurise to
0.15 wt% in order to improve the product quality.
2.3.1.6 LPG Treating and Recovery Unit (3,480 BPSD):
In this unit, raw LPG from Naphtha Hydrodesulphuriser and Catalytic Reformer
Unit are processed.
The butane that produced in this unit is used as a blending component in
Gasoline.
Besides that, the butane also can blended with Propane in order to form LPG
for domestic use.
2.3.1.7 Excess Naphtha Stabilizer Unit (3,325 BPSD):
Excess Naphtha from Crude Unit is stabilized.
2.3.1.8 Gas Sweetening Unit (35 tons/day H2S Removal):
Amine solution was used to sweetens the sour gas that produced in the refinery
facilities so that to remove any hydrogen sulphide inn order to minimize sulphur
oxide emissions.
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2.3.1.9 Sulphur Recovery Unit (35 tons/day):
The acid gases produced from Gas Sweetening Unit are converted to liquid
sulphur.
2.3.1.10 Jarn Yaphour Crude Oil Stabilization Plant (10,000 BPSD):
The Oil/Gas Separation Plant is designed to stabilize Crude from Jarn Yaphour
Wells, located some 30 kilometers from Abu Dhabi.
The separated gas is further treated to remove hydrogen sulphide, water and
hydrocarbon condensate before it is injected into GASCOs Main Gas Network.
2.3.2 Utilities, Off-sites, Terminal & ADR Technology
Additional Effluent Water Treatment facilities were installed to adhere to rigid oil in
water specification of 10 ppm maximum.
2.3.2.1 Utilities
Power and fresh was supplied from the adjacent plant of the Abu Dhabi Water
and Electricity Authority to the refinery.
Steam, Air, Nitrogen and Sea Water for cooling are all provided by the Refinery's
own facilities.
The Refinerys Fuel Gas supply is supplemented by Natural Gas from the GASCO
Main Network.
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2.3.2.2 Off-sites
The storage capacity of Abu Dhabi Refinery Tank Farm is 500,000 cubic meters,
which includes facilities for Crude Oil, Intermediate Streams, Semi-Finished
Products, Finished Products and Utility Fuel Oil.
The Residue and Naphtha are shipped to Ruwais Refinery while most of the
Refined Products from Abu Dhabi Refinery are sold in the ever expanding
domestic market.
2.3.2.3 Marine Terminal
The Refinery is served by a two-Berth Marine Terminal on the North Shore of
the Island for loading and unloading of tankers.
Maximum Draft is 9.5 meters; maximum Cargo is 30,000 tons.
2.3.2.4 ADR Technology
Abu Dhabi Refinery completed the process of installing a fully integrated state-
of-the-art Computerized System designed to Modernize Operations in the year
1994.
In January 1993, the first level was achieved with the commissioning of a new
Consolidated Control Room under the overall Refinery expansion project.
The Refinery is equipped with a Distributed Control System (DCS).
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DCS allowed for the introduction of an Advanced Process Control system as
part of the Process Automation and Computerization project (PACS).
PACS are designed to provide accurate and up-to-the-minute information on
every aspect of the Operations in Support of Operational and Management
Activities.
On the other hand, the second level of the project includes the implementation
of Advanced Process Control (APC) strategies and off-site Automation and
Computerization.
Third level involved the implementation of a plant-wide Data Base and
Communications Network, leading to the use of a Computerized Decision
Support System in laboratory management, Planning, Scheduling, Mass
Balancing, Oil Accounting and Performance Monitoring.
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CRUDE DISTILLATION UNIT
NAPHTHA HYDRODESULPHURISER UNIT
KEROSENE MEROX UNIT
CATALYTIC REFORMER UNIT
GAS OIL HYDRODESULPHURISER UNIT
LPG TREATING AND RECOVERY UNIT
EXCESS NAPHTHA STABILIZER UNIT
GAS SWEETENING UNIT
SULPHUR RECOVERY UNIT
CRUDE OIL STABILIZATION PLANT
85 000 BPSDFrom crude oil to fraction of naphtha, kerosene, gas oil and straight run residue
22 795 BPSDFrom straight run naphtha to heavy naphtha, light naphtha and sour liquefied petroleum gaese
21 250 BPSDFrom mercaptans to disulphide
14 000 BPSDFrom heavy naphtha cut to gasoline blending component
22 500 BPSDProduct: Reduced sulphur content of gas oil
3 480 BPSDProduct: Processed LPG
3 325 BPSDProduct: Stabilized naphtha
35 tons/day H2S removalProduct: Sweetened sour gases
35 tons/dayFrom acid gases to liquid sulphur
10 000 BPSDProduct: Stabilized crude
ABU DHABI REFINERY
Figure 2.4: Overall operation in Abu Dhabi Oil Refinery Company
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2.4 Mass Balance Based 400,000 BPD of Middle East Heavy Crude
By referring to US Petroleum Refinery Balance (Millions Barrels Per Day, Except Utilization Factor) as shown below:
Figure 2.5: US Petroleum Refinery Balance (Millions Barrels Per Day, Except Utilization Factor)
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2.4.1 Mass Balance by Assumed Proportion of Refining Products is Double
Figure 2.6: By referring to the diagram above which consists of 200,000
barrels per day
(Source: Environmental Aspects in Refineries and Projects, 2012)
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It is found that if the feedstock which is the 400 000 BPD Middle East heavy crude and assumed that the proportion of the refining
products is double and the number of the condensate is 560,000bbl/day, the final product will be shown in Table 2.1 below:
Table 2.1: Calculation of final product from 400 000 BPD Middle East heavy crude
Products
Quantity
(200,000 BPD) Fraction Percentage (%)
Mass balance
(400,000 BPD)
Gasoline 55000 0.138 13.836478 110000
Fuel oil 31000 0.078 7.798742138 62000
Jet fuel & kerosene 112000 0.2818 28.17610063 224000
Gas oil 89000 0.2239 22.38993711 178000
LPG 16000 0.0403 4.025157233 32000
Naphta 94500 0.2377 23.77358491 189000
Total 397500 1 100 795000
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Figure 2.7: Comparison quantity of product produced
110000
62000
224000
178000
32000
189000
795000
0
100000
200000
300000
400000
500000
600000
700000
800000
900000
Gasoline Fuel oil Jet fuel &kerosene
Gas oil LPG Naphta Total
Mass balance (400000bbl/d) (BPD)
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2.4.2 Mass Balance by Fraction Method
Based on the production of Abu Dhabi Oil Refining Company (refinery plant) at the
year of 1996, the mass balance is done using fraction method.
Table 2.2: Calculation of final product from 400 000 BPD Middle East
heavy crude
Products Quantity
(BPD) Fraction
Percentage
(%)
Mass balance
(BPD)
Gasoline 46100 0.199222 19.92 79688.85048
Fuel oil 67000 0.289542 28.95 115816.7675
Jet fuel & kerosene 36200 0.156439 15.64 62575.62662
Gas oil 70000 0.302506 30.25 121002.5929
LPG 7100 0.030683 3.07 12273.12014
Asphalt 5000 0.021608 2.26 8643.042351
Total 231400 1 100 400 000
** This analysis is done based on a production rate from Abu Dhabi Oil Refining
Company (refinery plant) using heavy crude oil
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Figure 2.8: Comparison quantity of product produced
0
20000
40000
60000
80000
100000
120000
140000
QU
AN
TITY
(B
PD
)
PRODUCT
Gasoline Fuel oil Jet fuel & kerosene Gas oil LPG Asphalt
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2.4.3 Mass Balance based on Total Production from while Middle East Countries
There can be another analysis based on the total production from whole Middle East countries
MIDDLE EAST COUNTRIES STATISTIC
Table 2.3: Middle East Output of Refined Petroleum Products, 2005 (Thousand Barrels per Day)
Energy Information Administration, International Energy Annual 2006 Table Posted: December 8, 2008
Country
Motor
Gasoline
Jet
Fuel
Kerosene
Distillate
Fuel
Oil
Residual
Fuel
Oil
Liquefied
Petroleum
Gases
Other
Total Output of
Refined Petroleum
Products
Refinery
Fuel and
Loss
Bahrain 17.64 49.45 8.47 91.97 52.13 1.18 47.63 268.47 10.74
Iran 260.67 18.47 127.66 499.57 480.16 135.58 166.82 1,688.93 67.56
Iraq 74.43 12.82 23.19 104.40 152.15 36.61 51.83 455.44 17.52
Israel 63.78 24.16 3.37 62.22 49.95 18.32 23.12 244.90 9.42
Jordan 14.33 7.04 4.89 28.53 27.91 3.87 5.15 91.73 3.53
Kuwait 65.48 50.27 128.30 245.77 179.47 149.41 222.99 1,041.68 40.06
Lebanon 0 0 0 0 0 0 0 0 0
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Oman 14.84 3.69 0.23 14.61 34.92 2.42 0.48 71.20 2.85
Qatar 40.31 20.10 0.08 18.94 14.23 81.83 5.67 181.16 6.97
Saudi Arabia 347.63 143.98 81.51 647.59 487.58 34.90 343.49 2,086.68 83.47
Syria 31.95 4.80 1.14 74.96 88.01 10.77 43.19 254.81 9.80
United Arab Emirates 43.73 117.71 0 87.41 28.67 16.63 93.27 387.42 14.90
Yemen 27.93 8.02 2.31 19.61 8.24 3.09 6.73 75.93 2.92
Middle East 1,002.71 460.50 381.16 1,895.59 1,603.44 494.59 1,010.36 6,848.35 269.73
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Figure 2.9: Fraction of Middle East Output on 2005
motor gasoline15%
jet fuel7%
kerosene5%
fuel oil28%
fuel oil23%
petroleum gases7%
other15%
Middle East Output of Refined Petroleum Product on 2005
motor gasoline jet fuel kerosene fuel oil fuel oil petroleum gases other
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Table 2.4: Calculation of final product from 400,000 BPD Middle East
heavy crude
Products Quantity
(BPD) Fraction
Percentage
(%)
Mass balance
(BPD)
Gasoline 1002.71 0.146416 14.64 58566.51602
Fuel oil 1895.59 0.276795 27.68 110718.0562
Jet fuel 460.5 0.067242 6.72 26896.98979
Kerosene 381.16 0.055657 5.57 22262.88084
LPG 494.59 0.07222 7.22 28888.12634
Asphalt 1010.36 0.147533 14.75 59013.33898
Residual fuel oil 1603.44 0.234135 23.41 93654.09186
TOTAL 6848.35 1 100 400 000
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Figure 2.10: Comparison quantity of product produced
0
20000
40000
60000
80000
100000
120000
Qu
anti
ty (
BP
D)
Product
Gasoline Fuel oil Jet fuel Kerosene LPG Asphalt Residual fuel oil
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2.5 Conclusion
With the increasing world energy demand, this situation has pushed the oil producing
countries, Middle East Countries, to start exploiting heavy oil reservoirs, which had
been neglected or little used and to increase the oil exploration activities. Currently,
there are some heavyweight producers such as Saudi Arabia, Venezuela and Iran
produce large quantities of heavy ( API < 20) sour crude with high sulfur content.
However, others such as Nigeria, the United Arab Emirates, Angola and Libya pump a
higher quality, light sweet crude, with low sulfur content.
Since the global energy demand is keep increasing, this has putting up pressure
on the major oil producing countries to increase their production capacities. With
Middle East Countries alone, the production capacity is expected to reach 4 million
barrels per day (MBPD) by the year of 2020 has reach.
It is important for the Middle East Countries to maintain its market share
besides increase production capacity. However, heavy crude oil (API < 20) must be
also used as gap filler.
Basically, these current events are facing the oil industry in Middle East
Countries with many decisions and technological challenges, including counteracting
expected increased risk of corrosion and equipment failures during the production and
refining of heavy crude oil. Inorganic salts, organic chlorides, organic acids, and sulfur
compounds can be consider as the most damaging impurities.
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Things might getting worst when many of the compounds are unstable during
refining operations and they break into smaller components or combine with other
constituents, concentrating corrodants in certain units, such as the breakdown of
sulfur compounds and organic chlorides.
However, most of the world refineries including Kuwait are equipped with alloys
that capable of handling sweet light crude, which is most suitable for refining into
petrol, gas oil and heating oil. On the other hand, refining of heavy crude is difficult
and is associated with operational problems.
Problem can be arise from the increased risk of corrosion, equipment failures,
and downtime of process units. This problem are caused by the high sulfur and salt
contents of these crudes including organic chlorides.
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3.0 GROUP PROJECT
3.1 Introduction To Cumene Production
The commercial production of cumene is by FriedelCrafts alkylation of
benzene with propylene. In previously, solid phosphoric acid (SPA) supported
on alumina was used as the catalyst. Therefore, since the mid-1990s, commercial
production has switched to zeolite-based catalysts.
Isopropyl benzene is stable, but may form peroxides in storage if in contact
with the air. It is important to test for the presence of peroxides before heating or
distilling. The chemical is also flammable and incompatible with strong oxidizing agents.
Environmental laboratories commonly test isopropyl benzene using a Gas
chromatographymass spectrometry (GCMS) instrument.
3.1.1 Cumene Project Definition
Isopropylbenzene, also known as cumene, is among the top commodity chemicals,
taking about 7 8% from the total worldwide propylene consumption. Today, the
cumene is used almost exclusively for manufacturing phenol and acetone.
This case study deals with the design and simulation of a medium size plant of
100 kton cumene per year. The goal is performing the design by two essentially
different methods. The first one is a classical approach, which handles the process
synthesis and energy saving with distinct reaction and separation sections. In the
second alternative a more innovative technology is applied based on reactive
distillation.
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Table 3.1 presents the purity specifications. The target of design is achieving
over 99.9% purity. It may be seen that higher alkylbenzenes impurities are undesired.
Ethyl - and butylbenzene can be prevented by avoiding olefi ns and butylenes in the
propylene feed. N - propylbenzene appears by equilibrium between isomers and can
be controlled by catalyst selectivity.
In this project we consider as raw materials benzene of high purity and
propylene with only 10% propane. As an exercise, the reader can examine the impact
of higher propane ratios on design.
Table 3.1: Specifications For Cumene
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3.1.2 Cumene Manufacturing Routes
General information about chemistry, technology and economics can be found in the
standard encyclopaedic material, as well as in more specialized books. The
manufacturing process is based on the addition of propylene to benzene (Alexandre,
2008):
Beside isopropyl benzene (IPB) a substantial amount of polyalkylates is formed
by consecutive reactions, mostly as C6H5 - (C3H7) 2 (DIPB) with some C6H5 - (C3H7)
3 (TPB). The main reaction has a large exothermal effect, of 113 kJ/mol in standard
conditions. The alkylation reaction is promoted by acid - type catalysts.
The synthesis can be performed in gas or liquid phase. Before 1990 gas phase
alkylation processes dominated, but today liquid - phase processes with zeolite
catalysts prevail. Recent developments make use of reactive distillation.
Cumene processes based on zeolites are environmentally friendly, offering high
productivity and selectivity. The most important are listed in Table 3.2. The catalyst
performance determines the type and operational parameters of the reactor and,
accordingly the flowsheet configuration. The technology should find an efficient
solution for using the reaction heat inside the process and and/or making it available
to export. By converting the polyalkylbenzenes into cumene an overall yield of nearly
100% may be achieved.
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Table 3.2: Technologies for cumene manufacturing based on zeolites
Figure 3.1 illustrates a typical conceptual flowsheet. Propylene is dissolved in a
large excess of benzene (more than 5 : 1 molar ratio) at sufficiently high pressure that
ensures only one liquid phase at the reaction temperature, usually between 160 and
240 C. The alkylation reactor is a column filled with fixed-bed catalyst, designed to
ensure complete conversion of propylene. The reactor effluent is sent to the
separation section, in this case a series of four distillation columns: propane (LPG)
recovery, recycled benzene, cumene product and separation of polyisopropylbenzenes.
The flowsheet involves two recycles: nonreacted benzene to alkylation and
polyalkylbenzenes to transalkylation. The minimization of recycle flows and of energy
consumption in distillation are the key objectives of the design.
These can be achieved by employing a highly active and selective catalyst, as
well as by implementing advanced heat integration.
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Figure 3.1: Conceptual Flowsheet for cumene manufacturing by Dow-
kellogg process
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3.1.3 General Overall Material Balance for Cumene Process
Table 3.3 illustrates a typical material balance of a cumene plant using Dow-Kellog
technology. The propylene may contain up to 40% propane, but without ethylene and
butylene. Beside cumene, variable amounts of LPG can be obtained as subproducts.
Energy is also exported as LP steam, although it is consumed as well as other utilities
(fuel, cooling water, electricity).
Table 3.3: Overall Process Material Balance After Dow-Kellog Technology
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3.1.4 Physical Properties
Table 3.4 presents some fundamental physical constants. Critical pressures of propane
and propylene are above 40 bar, but in practice 20 to 30 bar are sufficient to ensure
a high concentration of propylene in the coreactant benzene. From the separation
viewpoint one may note large differences in the boiling points of components and no
azeotrope formation. In consequence, the design of the separation train should not
raise particular problems. Since the liquid mixtures behave almost ideally a deeper
thermodynamic analysis is not necessary. The use of vacuum distillation is expected
because of the high boiling points of the polyalkylated benzenes.
Table 3.4: Basic physical properties of components in the outlet reactor
mixture
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3.2 Cumene Process
The Cumene process (Cumene-phenol process, Hock process) is an industrial
process for developing phenol and acetone from benzene and propylene. The term
stems from cumene (isopropyl benzene), the intermediate material during the process.
It was invented by Heinrich Hock in 1944 and independently by R. dris and P.
Sergeyev in 1942 (USSR).
This process converts two relatively cheap starting
materials, benzene and propylene, into two more valuable ones, phenol and acetone.
Other reactants required are oxygen from air and small amounts of a radical initiator.
Most of the worldwide production of phenol and acetone is now based on this method.
In 2003, nearly 7 billion kg of phenol was produced by the Hock Process.
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3.3.1 Technical Description
Benzene and propylene are compressed together to a pressure of 30 standard
atmospheres at 250 C (482 F) in presence of a catalytic Lewis acid. Phosphoric
acid is often favored over aluminium halides. Cumene is formed in the gas-
phase Friedel-Crafts alkylation of benzene by propylene:
Cumene is oxidized in air which removes the tertiary benzylic hydrogen from
cumene and hence forms a cumene radical:
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3.2.1 Cumene Chemical Properties
Cumene is a colourless liquid, soluble in alcohol, carbon tetra chloride, ether and
benzene. It is insoluble in water. Cumene is oxidized in air which removes the
tertiary benzylic hydrogen from cumene and hence forms a cumene radical:
This cumene radical then bonds with an oxygen molecule to give cumene
hydroperoxide radical, which in turn forms cumene hydroperoxide (C6H5C(CH3)2-O-O-
H) by abstracting benzylic hydrogen from another cumene molecule.
This latter cumene converts into cumene radical and feeds back into
subsequent chain formations of cumene hydroperoxides. A pressure of 5 atm is used
to ensure that the unstable peroxide is kept in liquid state.
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Cumene hydroperoxide is then hydrolysed in an acidic medium (the Hock
rearrangement) to givephenol and acetone. In the first step, the terminal
hydroperoxy oxygen atom is protonated.
This is followed by a step in which the phenyl group migrates from the benzyl
carbon to the adjacent oxygen and a water molecule is lost, producing
a resonance stabilized tertiary carbocation.
The concerted mechanism of this step is similar to the mechanisms of
the Baeyer-Villiger oxidationand also the oxidation step of hydroboration-
oxidation.[6] In 2009, an acidified bentonite clay was proven to be a more economical
catalyst than sulfuric acid as the acid medium.
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As shown below, the resulting carbocation is then attacked by water, a proton
is then transferred from the hydroxy oxygen to the ether oxygen, and finally the ion
falls apart into phenol and acetone.
The products are extracted by distillation.
3.3 Chemical Reaction Network
The mechanism of benzene alkylation with propylene involves the protonation of the
catalyst acidic sites [5, 6] leading to isopropylbenzene, and further di-
isopropylbenzenes and tri - isopropylbenzenes. By the isomerization some n -
propylbenzene appears, which is highly undesirable as an impurity. The presence of
stronger acid sites favors the formation of propylene oligomers and other hydrocarbon
species. Therefore, high selectivity of the catalyst is as important as high activity. It is
remarkable that the polyalkylates byproducts can be reconverted to cumene by
reaction with benzene. Below, the chemical reactions of significance are listed:
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3.4 Various Processes of Manufacture
Currently almost all cumene is produced commercially by two processes. The first type
is A fixed bed, Kieselguhr supported phosphoric acid catalyst system developed by
UOP (Universal Oil Products Platforming Process). The second type is A homogeneous
AlCl3 and hydrogen chloride catalyst system developed by Monsanto.
3.4.1 UOP Cumene Process
Figure 3.5: PFD for UOP Cumene Process
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Propylene feed fresh benzene feed and recycle benzene are charged to the upflow
reactor, which operates at 3-4 Mpa and at 200-260C. The solid phosphoric acid
catalyst provides an essentially complete conversion of propylene on a one-pass basis.
The typical reactor effluent yield contains 94.8 Wt. % cumene and 3.1 Wt. %
of diiso propylbenzene. The remaining 2.1 % is primarily heavy aromatics. This high
yield of cumene is achieved without transalkylation of diiso propylbenzene and is
unique to the solid phosphoric acid catalyst process.
The cumene product is 99.9 Wt. % pure and the heavy aromatics, which have
an octane number of 109, can either be used as high octane gasoline blending
components or combined with additional benzene and sent to a transalkylation section
of the plant where diiso propylbenzene is converted to cumene.
The overall yields of cumene for this process are typically 97-98 Wt. % with
transalkylation and 94-96 Wt. % without transalkylation.
3.4.1.1 Application
To produce high-quality cumene (isopropylbenzene) by alkylating benzene with
propylene (typically renery or chemical Grade) using liquid-phase Q-Max process
based on zeolitic catalyst Technology.
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3.4.1.2 Description
Benzene is alkylated to cumene over a zeolite catalyst in a fixed-bed, liquid-phase
reactor. Fresh benzene is combined with recycle benzene and fed to the alkylation
reactor (1). The benzene feed flows in series through the beds, while fresh propylene
feed is distributed equally between the beds. This reaction is highly exothermic, and
heat is removed by recycling a portion of reactor effluent to the reactor inlet and
injecting cooled reactor effluent between the beds.
In the fractionation section, propane that accompanies the propylene feedstock
is recovered as LPG product from the overhead of the depropanizer column (2),
unreacted benzene is recovered from the overhead of the benzene column (4) and
cumene product is taken as overhead from the cumene column (5). Di-
isopropylbenzene (DIPB) is recovered in the overhead of the DIPB column (6) and
recycled to the transalkylation reactor (3) where it is transalkylated with benzene over
a second zeolite catalyst to produce additional cumene. A small quantity of heavy
byproduct is recovered from the bottom of the DIPB column (6) and is typically
blended to fuel oil. The cumene product has a high purity (99.96 99.97 wt%), and
cu