Transcript Production of synthesis gas

Production of Synthesis
Gas & Ethanol
Presented By :
(Group 1)
Beshayer Al-Dihani
Hessa Al-Sahlawi
Latifa AL-Qabandi
Supervised By:
Prof. Mohamed A. Fahim
Eng. Yusuf Ismail Ali
Contents
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Abstract
Introduction
Production of Synthesis Gas
Uses of Synthesis Gas
Production of Ethanol
Uses of Ethanol
Conclusion
Abstract
There are three methods for product
synthesis gas:
 First, synthesis gas produce by steam
reforming from natural gas.
• Second, is the partial oxidation from
natural gas.
• Third, is partial oxidation from vacuum
residue.
• Synthesis gas is used as raw material to
produce Ethanol.
Introduction
•
Synthesis gas generally refers to mixture
of carbon monoxide and hydrogen. The
ratio hydrogen to carbon monoxide varies
according to the type of feed, the method
of production, and the end use of the gas.
• Natural gas:
Natural gas is a vital component of
the world's supply of energy.
It is the cleanest, safest and most
useful of all energy sources. It is
consumed in residential, commercial,
industrial and utility market.
The different sources and
routs to
synthesis gas
Steam
Reforming
Natural Gas
Coal
Gasification
Synthesis
Gas
(Co, H2 Mixture)
Partial
Oxidation
Of natural gas
&
Petroleum
products
Steam
Reforming
Petroleum
Products
Method (1):
Steam reforming For Synthesis gas
Production from Natural gas:-
• Catalytic steam reforming is used to
convert hydrocarbon feeds to
synthesis gas by reaction with steam
over a nickel – based catalyst.
• The process is usually operated
between 800˚C and 1000 ˚C (1500 –
1800 ˚F) and 8 to 25 bars (100_350
psig) .
• For our process the raw materials
are :
• CH4,C2H6,C3H8,CO2,N2,O2,H2O
• The reactions are :
• CH4 +H2O  CO +3H2
• CH4 +2H2O + CO2  4CO +8H2
• It is an endothermic reaction
• The final product are :
• CH4,CO2,CO,H2,N2,H2O
Reformer Reactor / Furnace
• The reformer is a direct fired chemical reactor
consisting of numerous tubes located in fire box
and filled with catalyst.
• Conversion of hydrocarbon and steam to an
equilibrium mixture of hydrogen, carbon oxides
and residual methane takes place inside the
catalyst tubes.
• Heat for the highly endothermic reaction is
provided by burners in the firebox.
• The heat is transferred to the catalyst filled
reactor tubes by a combination of radiation and
convection.
• Reforming catalyst is available in many shapes
and sizes, each with specific advantages
according to the suppliers.
Different types and shapes
of catalyst
• Figure (5) is a flow sheet illustration
of our process concept for the
production of synthesis gas (H2: CO
ratio 2:1) by the steam reforming of
natural gas.
• process is divided into three
sections:
• Steam reforming and heat recovery
(section 100).
• Carbon dioxide separation (section
200).
• Hydrogen skimming (section 300).
Figure(5)
Method (2):
Production of synthesis gas (H2:CO=2:1)
from natural gas by partial oxidation
This process takes place @ high
temperature and pressure, but no
catalyst.
The reaction is called partial oxidation
because it is kept from going to CO2 by
limiting the amount of oxygen fed to
process.
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For our process the raw materials are :
CH4,C2H6,C3H8,CO2,N2,O2,H2O
The reaction is :
CH4 +½ O2  CO +2H2
It is an exothermic reaction
The final product are :
CH4,CO2,CO,H2,N2,H2O
•
Figure (7) is a flow sheet
illustration of our process concept
for the production of synthesis gas
(H2: CO ratio 2:1) by the partial
oxidation of natural gas.
• process is divided into three
sections:
1. Partial oxidation and heat recovery
(section 100).
2. Air separation (section 200).
3. Carbon dioxide separation (section
300).
Figure(7)
Method (3):
Synthesis gas (H2: CO = 2:1) from vacuum
residue by partial oxidation:
Process for the non – catalytic partial •
oxidation of hydrocarbons were
primarily developed for the gasification
of heavy petroleum feedstock's at the
bottom of the barrel, which can contain
high levels of sulfur and metallic oxides.
The feedstock's for the feed are :
Carbon,Hydrogen,Nitrogen,Sulfur
Ash,oxygen and water.
The reaction were take place in the
process are :
CnHmSr + n/2 O2  nCO + ( m/2-r)H2 +rH2S
CO + ½ O2  CO2
CO + H2O  CO2 + H2
COS + H2  CO + H2S
COS + H2O  CO2 + H2S
( CH2 ) n  ( CH4 ) n/2 + C n/2
CH4 + H2O  CO + 3 H2O
C+ CO2  2 CO
C + H2O  CO + H2
the reaction are exothermic
Process Description:
The process is divided to four sections:
1- Partial oxidation and heat recovery
(section 100).
2- Air separation (section 200).
3- Soot recovery and recycle (section
300).
4- Acid gas removal, CO shift, and sulfur
recovery (section 400).
First , in the Air separation section the oxygen are
produced with 99.5 vol% purity .
Second , in the soot recovery and recycle section the
Naphtha stripper recycle are produced which is fed
to oxidizer reactor .
Third, in the partial oxidation and heat recovery
section the vacuum feedstock's is fed to reactor with
blend of steam , oxygen form air separation section
and recycle Naphtha , the hot product are quench in
heat recovery then scrubbed with water so that can
send to soot recovery section and Acid gas removal
,co shift and sulfur recovery section .
Final, in the Acid gas removal ,co shift and sulfur
recovery section the CO2 and sulfur are removed
and the syngas will produce.
Partial oxidation and heat recovery
(section 100)
Air separation (Section 200)
Soot Recovery and Recycle (Section 300)
Acid Gas Removal and CO shift (Section 400)
Synthesis gas by other methods:
By coal gasification:
Manufacture of synthesis gas was based on coal
for many years before the introduction of steam
reforming, and in west Europe coal–based
production remained dominated until the 1960s.
The original method was generation from coke, by
the water gas reaction:
C + H2O  CO + H2
(c. 1200 C)
The heat required for this endothermic reaction is
providing by burring some of the coke:
C + O2  CO2
Operation is cyclic, with air and stream
alternately being blown through a bed of
coke. The process is extremely wasteful of
coke and of energy. More sophisticated and
efficient are coal gasification processes, in
which coal is treated with mixture of oxygen,
or air, and steam:
(O2, H2O)
Coal  CO + H2
(750- 1500 C)
Capital and operation costs for coal–based
manufacture of synthesis gas are much
higher than those for manufacture by
steam reforming largely because coal is
solid.
There is one country, south Africa, where
manufacture of synthesis gas from coal
has never been displaced by steam
reforming.
Uses of synthesis gas
The chief use of syngas is in:
1.
the manufacture of hydrogen for a
growing number of purposes.
2. Methanol not only remains the second
largest consumer of syngas but has
shown remarkable growth as part of the
methyl ethers used as octane enhancers
in automotive fuels.
3. The hydroformylation of olefins (the
oxo-reaction), a completely chemical
use of syngas.
Uses of synthesis gas
4. The Fischer-Tropsch synthesis
remains the third largest
consumer of syngas, mostly for
transportation fuels.
5. generation of electricity.
6. Syngas is the principal source of
carbon monoxide, which is used
in an expanding list of so-called
carbonylation reactions.
Production of Ethanol from
Syngas
• Ethyl alcohol has been produced by
fermentation of carbohydrates of
many thousands of years.
• Economic industrial manufacture of
synthetic ethyl alcohol began in the
1930s.
• The first process used was the
indirect catalytic hydration of
ethylene.
• This route has several
disadvantages:
• The large volumes of dilute
sulphuric acid to be handled.
• The energy required for its
concentration.
• Corrosion caused by the acid.
alternative routes based on methyl alcohol or synthesis
gas as starting materials has been developed.
Carbonylation
Syngas
Methanol
Hydrolysis
Acetic Acid
Ethanol
Another rout was developed to:
Syngas
RH
Ethanol
• The process was shown to be uneconomic:
• Inadequate selectivity to ethanol
• The very large amounts of rhodium catalyst required.
• SRI presents a speculative design for
an alternative process to produce
ethanol from synthesis gas.
• The process uses a copper-cobalt
catalyst
• Conversion of synthesis gas to
ethanol can be carried out directly
4H2 + 2CO
CH3CH2OH + H2O
• The reaction is exothermic, with a
heat of reaction of -57.2 kcal/g-mol.
• Examples using these catalysts
mention the presence of carbon dioxide
in the feed synthesis gas.
• The carbon dioxide can react with
hydrogen as follows:
• 6H2 + 2CO2
CH3CH2OH + 3 H2O
• This reaction is exothermic, with a heat
of reaction - 37.5 kcal/g-mol.
Process Description
• The plant is designed to produce
ethanol as the principle product, in
the presence of the catalysts
(mixture of oxides of Cu, Co, Cr and K).
• The design that we will discuss has
two sections:
• Reaction section.
• Separation section.
• Fifteen days’ product storage is
provided for ethanol, methanol, and
mixed C3 alcohols. Storage is
provided for 48 hours of both the
gasoline feed to the extraction unit
and gasoline-plus-C4+ alcohols
product.
Summary of the process
• Feed is H2, CO, CO2 and N2.
• The products from reaction
section are H2O, methanol,
ethanol, propanol, butanol,
pentanol, hexanol and heptanol.
• The final products are methanol,
ETHANOL and propanol.
Uses of Ethanol
Medically, ethanol is:
• a soporific, i.e., sleep producing;
although it
• less toxic than the other alcohols,
death usually occurs if the
concentration of ethanol in the
bloodstream exceeds about 5%.
Uses of Ethanol
• Ethanol is used:
• In the manufacture of alcoholic
drinks.
• As a solvent for paint, varnish and
drugs.
• In the manufacture of
acetaldehyde and acetic acid.
Uses of Ethanol
• As a fuel (e.g. in Gasahol).
• As the fluid in thermometers.
• In preserving biological
specimens.
• Ethanol is also used in design and
sketch art markers
CONCLUSION
• We conclude that there are many
ways to produce synthesis gas:
• Stem reforming from natural gas.
• Partial oxidization from natural
gas and from vacuum residue.
• There are many ways to produce
ethanol, but we choose direct
synthesis method from syngas.
Thank you for
your attention