Transcript Document

Energy Efficiency and Innovative Emerging
Technologies for Olefin Production
T. Ren
Utrecht University, The Netherlands
Email: [email protected], Heidelberglaan 2, 3584 CS
Sponsored by Utrecht Energy Research Center (UCE) and
Energy Research Foundation (ECN)
European Conference on Energy Efficiency
in IPPC-Installations
On October 21-22, 2004 in Vienna, Austria
Copernicus Institute
Sustainable Development and Transition Management
In this presentation
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Introduction to olefins
Energy use and CO2 emissions
Energy analysis
State-of-the-art
Innovations
Conclusion
Next step
Where is the Olefin Industry?
IPTS 2000
Light olefins and Steam Cracking
Ethylene (C2H4) and
Propylene (C3H6)
are two most important light olefins
They are the building blocks
of the chemical industry.
Their production process, steam cracking,
has the backbone status for the sector.
Used in the production of plastics, fibers, lubricants, films,
textiles, pharmaceuticals, etc. ---even chewing gum!
BASF 2000
Steam
Cracking
Energy Use and Emission
from Steam Cracking
• Steam cracking is the single most energy
consuming processes in the chemical industry
ca. 30% of the sector’s total final energy use
and ca. 180 millions tons of CO2 in 2004
Another reason for innovation:
over 35% of European crackers are over 25 years old
Estimated Global Energy Use and Emission 2004
World
US
Europe (including new EU
member states and FSU)
Total feedstock (Million
tons)
300
85
90
Breakdown of
Feedstock (wt. %)
naphtha 55,
ethane 30,
LPG 10,
gas oil 5
ethane 55,
naphtha 23,
propane15,
gas oil 5
naphtha 75,
LPG 10,
gas oil 9,
ethane 5
Ethylene capacity
(Million tons)
110-113
28-30
30-32 (23-24 by
Western Europe)
Propylene capacity
(Million tons)
53-55
16-17
17-18
2-3
0.5-0.6
0.7-0.8
180-200
43-45
53-55
Total process energy
(fuel combustion and
utilities
included) (EJ)
Total CO2 emission
(fuel combustion, decoking
and utilities included)
(Million tons)
Conventional Naphtha-based Steam Cracking Process
IPPC/BREF 2001
A naphtha steam cracker (900 kt/a) at Shell Moerdijk, the Netherlands
Shell 2003
Energy/Exergy Analysis
Ethane
Pyrol
ysis
Heat of
reaction
Steam,
heating
&losses
Fractionation and
Compression
Naphtha
Process
Energy
Process Energy
[27]
[31]
23%
65%
24%
22%
15%
Exergy loss
Our
estimate
Fuel combustion
and heat transfer to
the furnace
Heat exchange with
steam, TLEs and
heat loss to flue gas
75% (or
15 GJ/t
ethylene)
[26]
73%
N/A
27%
Fractionationf and
Compression
19%
12%
De-methanization
De-ethanizer and
C2 splitter
C3 splitter
Separation
31%
20%
De-propanization/
De-butanization
Ethylene
refrigeration
25% (2
GJ/t
ethylene
in
compressio
n and the
rest of
separation
processes)
23%
N/A
100%
100%
Total exergy losses
2%
10%
5%
Propylene
refrigeration
Total process
energy use
[80]
[20]
30%
100% or
17 GJ/t
ethylene
100% (only
pyrolysis
section)
100% (only
compression
and separation)
Conclusions from Energy Analysis
• Pyrolysis section is the most energy
consuming section (65% of the total energy
use and 75% the total exergy losses)
• Also energy consuming (each ca. 15-20%):
– Refrigeration and C2 separation
– Fractionation and compression
State-of-the-Art Naphtha Steam Cracking Processes
Licensors
Technip-Coflexip
ABB Lummus
Linde AG
Stone & Webster
Kellogg & Brown Root
Coil related
furnace
features
Radiant coils
pretreated to reduce
coking with a sulfursilica mixture
Double pass radiant
coil design; online
decoking reduces
emissions
Twin-radiant-cell
design (single split)
is 13m (shorter than
the average length
25m)
Twin-radiant-cell
design and quadracracking
Coil design (straight,
small diameter), low
reaction time; very high
severity
Double
de-methanizing
stripping system
De-methanizer with
low refrigeration
demand
Front-end demethanizer and
hydrogenation
De-methanization
simultaneous mass
transfer and heat
transfer
Absorption-based
demethanization system
with front-end design
N/a
Ca. 3 GJ/t
ethylene saved
N/a
Offered but no data
N/a
Ethylene
Yield
(wt. %)
35%
34.4%
35%
N/a
38%
SEC
(GJ/t
ethylene)
18.8-20 (best)
or 21.6-25.2 (typical)
18 (with gas turbine);
21 (typical)
21 (best)
20-25
No data
Demethanizer
separation
features
Gas Turbine
Conclusion: 20% of energy savings on the current energy use
(25-30 GJ/t ethylene) of naphtha steam cracking are possible.
Advanced naphtha steam cracking
• Advanced furnace materials (e.g. low coking
coating)
• Vacuum Swing Adsorption, mechanical vapor
recompression
• Advanced distillation columns, membrane and
combined refrigeration systems
• Conclusion: up to 20% energy savings are possible in
the pyrolysis section and up to 15% energy savings are
possible in the compression and separation sections.
Innovative Olefin Technologies
Gas Stream
Technologies
Ethane
Oxidative Dehydrogenation
Propane
Oxidative
dehydrogenation
Catalytic
cracking of
naphtha
Hydropyrolysis of
Naphtha
Feed
Ethane and
other gas
feedstock
Ethane and
oxygen
Propane and
oxygen
Naphtha
Olefins
Ethylene
Ethylene
Propylene
Ethylene/propylene
Shockwave,
combustion
gas; shift
syngas;
plasma; etc.
Alloy Catalyst
Reactor with
hydrogen co feed
Both a stem
reformer and an
(oxy-reactor); or,
cyclic fixed-bed
N/a
Mordenite zeolite
Zinc and calcium
aluminate based
625-700
900-1100
Shockwave:
ca. 8-10 GJ/t
ethylene/HVCs
Reactor
Catalyst
Temp.
oC
Process
energy
(SEC)i
Yield
(wt. %)j
Current
status
Byproduct upgrading
(C4-9)
Catalytic Pyrolysis
Process (CPP)
Naphtha
C4-C9 (from steam
cracking, refinery, etc.)
Crude oil, refinery
heavy oils, residues,
atmospheric gas oil,
vacuum gas oil
Ethylene
Propylene
Ethylene/propylene
Reactors with
hydrogen co
feed but less
steam
Fixed or fluidized bed
Riser and transfer line
reactor
Zeolite (or various
metal oxides)
N/a
Zeolite
Acidic zeolite (Lewis
sites)
550-600
650-680
785-825
580-650
650-750
Dow: ca. 10-12
GJ/t
ethylene/HVCs
Uhde: ca. 8-10
GJ/t propylene;
ca. 8-10 GJ/t
HVCs
KRICT: ca. 19 GJ/t
ethylene and ca. 10
GJ/t HVCs
Blachownia: ca.
16-20 GJ/t
ethylene and
ca. 10-13 GJ/t
HVCs
Shockwave:
highest
ethylene yield
ca. 90%
Dow: final
ethylene ca. 53%
if
weighted against
ethane and
oxygen
Uhde: propylene
final yield ca.
78% if weighted
against propane
and oxygen
KRICT: ethylene
38%, propylene
17-20%, aromatics
30% and HVCs
73%
Blachownia:
Ethylene yield
36-40% and
HVCs yield
70%
UOP: total propylene
yield from steam
cracking is 30% and
HVCs yield 85%
CPP: ethylene 21%,
propylene 18%, C4
11%, aromatics 15%
and
HVCs yield 60%
Lab
Lab
Commercially
available
Pilot plant
Commercially
available
Commercially available
Lab and near
commercialization
Fluidized bed
N/a
CPP: ca. 35 GJ/t
ethylene and ca. 12
GJ/t HVCs
CHEEC Project
by Dow and SABIC (NL)
• CHEEC (Cheap Energy Efficient Ethylene
Cracking)—catalytic olefin technology!
• Yield of ethylene and propylene together up
by 24%
• Energy use reduced by 20%
• Investment lowered by 27% and variable
costs lowered by 14%
Novem 2003
Conclusions from Innovative Olefin Technologies
• Catalytic olefin technologies produce high yield
of valuable chemicals (in particular) propylene
from low-cost feedstocks at lower reaction
temperature
• Special reactors, catalysts or additional materials
(oxygen, hydrogen, etc.) can be applied to reduce
energy consumption
• Up to ca. 20% energy savings are possible (on 1114 GJ/t high value chemicals of energy use by
state-of-the-art naphtha steam cracking)
Overall Conclusions
• Pyrolysis section is the most energy
consuming in a steam cracker
• Plenty of room for energy savings is
possible in steam cracking
• Catalytic olefin technologies can lead to
energy saving (up to 20%) on energy use
by state-of-the-art steam cracking
Ca. 90% chemical processes already benefits from catalysis,
so can steam cracking!
Our Next Step
• Energy and economic
analysis for Natural gasto-Olefin technologies
have been completed—
one conclusion is that at
this moment there are no
energy saving (75% more
energy use and only
feasible in locations where
prices of natural gas are
very low $0.75-1.0/GJ)
• Barriers/drivers and
their implications for
innovation in the
(bulk) chemical
industry are being
studied
• Policies and strategies
for stimulating
innovation will be
recommended
Thank you! Questions?
Some Backup Sheets
Why Do Catalytic Olefin Technologies Save Energy?
Energy
Energy saving!
Activation Energy
without catalysts
Ren 2003
Process energy required in a pyrolysis furnace
In the case of conventional steam cracking
Process energy required in a reactor
In the case of catalytic olefin technologies
Activation Energy
with catalysts
Thermodynamic
energy requirement
Olefins and byproducts
Ethane, naphtha or other feedstocks
Progress of Cracking Process
Simplified Chemical Reactions by Conventional
Naphtha Cracking (or Thermal Cracking)
Naphtha
Thermal Cracking
Free radicals
Reorganization
Ethylene
Propylene
Simplified Chemical Reactions by
Catalytic Naphtha Cracking
Naphtha
Thermal cracking
Catalytic cracking
etc.
etc.
Free radicals
Carbonium ions
Zeolite Catalysts
Reorganization
Ethylene
Propylene
Drivers/Barriers (1/2)
• Economic Drivers
• Economic Barriers
• Lower energy costs
• Value added (from
low-cost feedstock to
high value chemicals)
• Strong propylene
demand
• New plant investment in
the range of 500 million
to 1 billion euros
• Most old plants run with
zero depreciation, low
margins and overcapacity
Drivers/Barriers (2/2)
• Technical Drivers
• Technical Barriers
• Rapid advances in
R&D on new catalysts
• Spillover from
extensive technical
experience in refinery
catalysts
• Low olefin yield and
high byproduct yield
• Reaction and oxygen
use
• Coking and “spent
catalysts”