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PETROCHEMICALS
BYNibir Pawan Das
What are “Petrochemicals”?
Petrochemicals are:Chemicals products.Derived from Petroleum.Also from Fossil Fuels and Renewable
sources.
Major petrochemical products
Primary polymer resins and plasticisers:PVC.LDPE/HDPE.POLYSTYRENE.
Fibers:Acrylic fiber.Nylon.Polyester.
Major petrochemical productsChemicals:Dye stuff and chemical intermediates.Pharmaceuticals.Detergents.
Requirements of Petrochemical Industry
To meet the increasing demand.Vital for economic growth.Self-sufficiency by decreasing imports.
Structure of Petrochemical industry:Feedstock
Building blocks
Intermediates
Final Products
Processes InvolvedCracking:Thermal cracking.Catalytic cracking.
Reforming:Catalytic reforming.Steam reforming.
Naphtha Cracking
Steam cracking.Catalytic cracking.
The back-bone of petrochemical industry
Naphtha
Aromatic Olefins
Crac
kin
g
Crackin
g
Steam cracking.Steam cracking is a Pyrolysis process ,
involving cracking and de-hydrogenation.
Heating of hydrocarbons in the presence of steam.
Endothermic.Less residence time.
Motivation for steam cracking
The worldwide demand and production of olefins…
Currently, production through steam cracking
1. 94% of the world propylene.
2. In Western Europe, 95% of
ethylene and 70–75% of propylene.3. In Asia, 61% of ethylene.
Process of steam cracking of naphtha
Pyrolysis section
Fractionation andCompression Section
Product recovery and Separation Section
Naphtha
Pyrolysis section
Pyrolysis furnace
Transfer line exchange
(producing steam)
Cracked gas
Naphtha 650 - 750
300
Separation
section
Ethylene (24%)
Propylene(20%)
Butadiene(3%)
BTX(1%)
Petroleum ether(25%)
Products from separation section
Process conditions:Pressure 2-3 bar.
Temperature 800 -850 0C.
Residence time 0.1 – 0.5 seconds.
Dilution steam ratio 0.3 – 0.8 kg/kg
Chemistry of steam cracking
Propagation
Initiation
+ =C +
Terminatio
n
Severity vs Product yield
Energy analysis in steam cracking sections
Section Energy required
Energy loss
Pyrolysis 65% 75%Fractionation and Compression
15% 25%
Recovery section
20% 15%
Latest Development in steam cracking of naphtha
Advanced furnace materials
Advanced distillation column
Membranes
zeolite
Alternative technologies
Catalytic cracking of naphtha
Hydro-pyrolysis of naphtha
Use of products of steam cracking of naphtha
References• Olefins from conventional and heavy feedstock's:
Energy use in steam cracking and alternative processes. Energy 31 (2006) 425-251.. By Tao Ren, Martin Patel, Kornelis Blok.
• www.ihs.com• www.afpm.com• www.petrochem.net• www.ficci.com
Thank you