SC2 cracking furnace
These chemical converter units are the
Pyrolysis Furnaces
Long carbon chain molecules cracking to smaller
parts in the special alloy tubes in the radiation
zone (800 – 850 °C)
SC-1 block diagram
Information about polymer units of TVK
„…locally large, but globally small,
…how can we do anymore? „
Basic behavior of polyolefin units
Low MI
PP4
PP3
Average cycle lenght
Op
Qu
alit
y co
ntr
ol
~31 days
10~11
17~18
24
29
Nr. of transitions/cycle
9~10
16~17
Off-spec. ratio
1,1%
0,1%
Transition grade ratio
2,3%
1,7%
Final product
Production
L
tic
s
i
og
High MI
* Transition grades were created in Q4, 2012
PP-4
~33 days
Reactor grades
COPO
ent
lopm
Deve
HOMO
Polymer
Units
PP-3
TVK’s PP in 2012
Co
n
Co troll
un ing
tin /
g
Sales&
Marketing
tim
izat
ion
nce
a
n
e
nt
Mai
Cyclical industry with frequent transitions on a
dynamic market
PE-1/LD2
PE-1/HD1
Average cycle
lenght
~24 days
~28 days
~30 days
Reactor grades
7
9
7
Final product
11
10~11
10
Nr. of
transitions/cycle
6
4/line
6
Off-spec. ratio
5,1%
1,8%
1,07%
Transition grade
ratio
0,8%
0,2%*
0,3%*
TVK’s PE in
2012
PE-2
TVK’s polymer technology review
The „troops” that we have
PolyPropylene
PP: linear polymer built from propylene and in some cases contains also ethylene
Tradename: Tipplen (TVK)
Three main types: homo PP, random copolymer PP (C2: 0.5-6.5%) and block
copolymer PP (C2: 5-25%)
Properties:
Melt index: 0.2 - 80g/10 min (230oC/2,16 kg)
C2 content: 0.5 – 20wt%
Melting range: 140 – 165oC
Licensors:
PP3; PP4: LyondellBasell / Spheripol (loop Rx with monomer as diluent)
PP-3 Unit – 100 KTA (1989) PP-4 Unit – 180KTA (1999)
Spheripol PP advantage-disadvantage
Bulk Loop vs. Gas phase reactor technology

Higher CAPEX

Easy Temperature Control at Reactors

Shorter Grade Transition Time

Narrower Product Portfolio (It means lower C2 content random
PP, TPO grades)

Lower Volatile Content in PP (Just at CR grades)

Better Catalyst Activity
Low Density Polyethylene
LDPE technologies: autoclave/tubular reactor
LDPE-2 Plant started in 1991.
Annual capacity: 65 kt
Product
Tradename: Tipolen
Density: 0.919 – 0.925 g/cm3
Melt index: 0.2 – 4.6 g/10 min (190oC/2.16 kg)
Main application: film blowing
Licensor: LyondellBasell
tubular
autoclave
LDPE tubular vs. autoclave
Shematic process of LDPE-2 Plant
Polymerisation type: free radical
 monomer:
 iniciator:
growth
 modificator:
 comonomer:
radical formation  starting of chain
transmitting radical activity  termination
plasticity, polarity, shining of the product
High/Medium Density Polyethylene
HDPE/MDPE: Polyethylene having only short chain branches on the linear
main chain
Tradename: Tipelin (TVK)
Properties:
Density: 0.935 – 0.965 g/cm3
Melt index: 0.1 - 50 g/10 min (190 oC/2,16 kg)
Melting range: 125 – 135oC
Licensor:
PE1/ HDPE-1: Chevron Phillips (loop Rx with light diluent)
PE2 / HDPE-2: Mitsui Chemicals Inc. (stirred tank Rx with heavy diluent)
No of SCB
LLDPE
MDPE
HDPE
0,915
0,926
0,940
0,970
PE-1/HDPE-1 Unit – 200KTA (1986)
Loop Reactor
(90 – 106°C; 42barg)
Flash Tank (60°C; 0,3barg)
Flash Gas to
recycling system
ethylene
hexene-1
hydrogen
Cyclon
e
Treaters
isobutane
Dryer (70°C)
Bag Filter
HDPE fluff to
powder silos
Purge Column (75°C)
Powder
Silos
(8pcs)
Additives
Homogenizer
Repellet
Scales
Dryer
HDPE pellets
Classifier
• Silo farm (28 silos)
• Bagging machines (2 lines)
• Truck loading facility
Continuous Intensive Mixer (CIM)
Extruder (210°C)
PE-2 / HDPE-2 Unit – 220KTA 2004
Comonomer
Centrifuge
H2
Daily
tank
TEAL
Dryer / 105°C
Mixing
silo
Pellet
Silo
Homogenizer
VOC: ~33 -> 0,1wt%
Powder
Silo
R1: 85°C/7barg
220°C
R2: 75°C/2.5barg
Packaging
Fresh
solvent
Termék
Solvent
tank
2/3
1/3
Low Polymer (LP)
Advantages, disadvantages in the HDPE units
PE-1/HDPE1











vs.
Less rotation maschine - Higher reliability
Excellent diluent recovery
Broad density range (0,962-0,935)
Lower catalyst costs
Less steam consumption
Lower volatile content (instead of MDPE)
MI correction in the extrusion section
Higher electricity consumption
Just monomodal products
Longer transitions
Lower flexibility
PE-2/HDPE-2











Wider product range (mono and bimodal)
Shorter grade transition time
High flexibility
Lower pressure in the reactor part
Start and stop without flaring
Lower ESP in the extrusion section
Possibility to use C3- instead of purchased
co-monomer
Higher steam consumption in the diluent
recovery section
Higher specific diluent consumption
Higher volatile content
Higher maintenance costs
Process Control - Optimization
Try to find….
…keep it…
…automate it.
General process control scheme
APC
DCS Basic
Control level
Process – Field
level
Optimization
3 basic rules:
1 – Safety
2 – Quality
3 – Economic goals
The economical situation
forces the polymer producers
to find „new operating
region”, and they would be
able to adopt new technics to
remained there in every
different workpoints.
APC the most common tool for optimization


The APC is not a „magic weapon”. This is that tool wich can help us to keep the plant
near to the optimum continuously if the operators are familiare with that.
The two most critical behaviors of a polymer plant: Non-linearity, multivariable
Thank you for your kind attention!