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Production of Syngas and EthanolProduction of Syngas and Ethanol
Group IIGroup II
Definition of SyngasDefinition of SyngasSyngas is the abbreviated name for synthesis gas. It is a gas mixture that comprises of hydrogen and carbon monoxide.
1:2CO:Η2
components of syngas
Importance of Synthesis GasImportance of Synthesis Gas
The rising cost of petroleum has motivated the examination of alternative feedstocks for chemical production. One such feedstock is synthesis gas.
The major components of syngas, hydrogen and carbon monoxide, are the basic building blocks of a number of other products.
In the future, syngas will become increasingly important for the production of cleaner fuels. The huge potential market for syngas is illustrated by the fact that almost 20% of the present world primary energy consumption is for transportation fuels only. If the chemical sector is included, the total syngas potential increases to approximately 30%.
Routes to SyngasRoutes to Syngas
There are three main routes to the production of synthesis gas:
• steam reforming of natural gas• partial oxidation of natural gas• partial oxidation of vacuum residuum
Methods of ProductionSteam Reforming of Natural GasMethods of ProductionSteam Reforming of Natural Gas
Raw Materials
Natural Gas - methane, CO2, nitrogen, ethane, C3
Air - nitrogen, oxygen
Water - H2O
Reactions
CH4+H2O → CO+3H2
3CH4+2H2O+CO2 → 4CO+8H2
Product
Syngas - methane, CO2, CO, hydrogen, nitrogen, water
Methods of ProductionSteam Reforming of Natural GasMethods of ProductionSteam Reforming of Natural Gas
SULFUR REMOVAL
STEAM REFORMING
HEAT RECOVERY
CO2
SEPARATIONHYDROGEN SKIMMING
natural gas
steam
raw syngas
syngas product
38°C
315 psia
244°C
310 psia885°C
295psia
49°C
280psia
54°C
253 psia
49
°C
28
3 p
sia
Methods of ProductionSteam Reforming of Natural GasMethods of ProductionSteam Reforming of Natural Gas
Methods of ProductionPartial Oxidation of Natural GasMethods of ProductionPartial Oxidation of Natural Gas
Raw Materials
Natural Gas - methane, CO2, nitrogen, ethane, C3
Oxygen - nitrogen, oxygen
Steam - H2O
Reactions
CH4+0.5O2 → CO+2H2
Product
Syngas - methane, CO2, CO, hydrogen, nitrogen, water
Methods of ProductionPartial Oxidation of Natural GasMethods of ProductionPartial Oxidation of Natural Gas
OXIDIZER REACTOR
HEAT RECOVERY
WATER SCRUBBER
CO2
SEPARATION
natural gas raw syngas
syngas product
49°C
962 psia
149°C
980 psia1350°C
371°C
1000 psia
steam
oxygen
49
°C
96
5 p
sia
waste water
CO2
Methods of ProductionPartial Oxidation of Natural GasMethods of ProductionPartial Oxidation of Natural Gas
Methods of ProductionPartial Oxidation of Vacuum Residuum
Methods of ProductionPartial Oxidation of Vacuum Residuum
Raw Materials
Vacuum Residuum - carbon, hydrogen, nitrogen, sulfur, ash
Oxygen - oxygen, nitrogen
Steam - H2O
Reaction
Products
Syngas - methane, CO2, CO, hydrogen, nitrogen, water
Methods of ProductionPartial Oxidation of Vacuum Residuum
Methods of ProductionPartial Oxidation of Vacuum Residuum
OXIDIZER REACTOR
HEAT RECOVERY
WATER SCRUBBERnatural gas
ACID GAS REMOVAL
CO SHIFT REACTOR
SULFUR RECOVERY
raw syngas
CO2-rich gas
soot + inorganic matter
tail gas
sulfur by-product
syngas product
45
7°C
10
00
psia
1320°C
49°C
945 psia
425°C
49
°C
91
5 p
sia
steam
oxygen
49
°C
94
5 p
sia
Methods of ProductionPartial Oxidation of Vacuum Residuum
Methods of ProductionPartial Oxidation of Vacuum Residuum
Additional Methods for Syngas Production
Additional Methods for Syngas Production
• Auto thermal reforming (ATR)
• Combined reforming
Additional Methods for Syngas Production
Auto thermal Reforming ATR
Additional Methods for Syngas Production
Auto thermal Reforming ATR
• This process combines partial oxidation and adiabatic steam reforming.
• A process consist of desulphurization , pre-heater, reactor , heat recovery and separation unit.
• A mixture of natural gas, oxygen and steam is fed to the reactor.
• The partial oxidation occur in a combustion area ,then the product pass through catalyst bed where reforming reaction occur.
• The temperature of the produced syngas is less than one of the partial reactor cause the catalyst does not support high T values.
Additional Methods for Syngas Production
Auto thermal Reforming ATR
Additional Methods for Syngas Production
Auto thermal Reforming ATR
Additional Methods for Syngas Production
Combined Reforming
Additional Methods for Syngas Production
Combined Reforming
• Combined reforming includes steam reformer and auto-thermic reactor .
• The combined reforming reactor advantages are:Control the H2/CO ratio in the synthesis.
• Oxygen used less than auto-thermic reforming and partial oxidation in the case of nitrogen free syngas.• Pressure can be increased with lower exit temperature of the reformer to reduce the size of the reactor 50% compared with steam reforming.• Increase the pressure with saving oxygen.• Hydrogen removed which leads less NOx emission compared with steam reforming .
Ethanol from Synthesis GasEthanol from Synthesis GasEthanol from Synthesis GasEthanol from Synthesis Gas
Currently all commercial synthetic ethanol is made by the hydration of ethylene. The rising price of petroleum-based ethylene has motivated the examination of routes to ethanol from syngas.
One such route is the direct synthesis of ethanol from syngas.
Production of EthanolProduction of EthanolDirect Synthesis of SyngasDirect Synthesis of SyngasProduction of EthanolProduction of EthanolDirect Synthesis of SyngasDirect Synthesis of Syngas
Raw materialsHydrogen, carbon monoxide, carbon dioxide, nitrogen
Reactions4H2 + 2CO → CH3CH2OH + H2O
6H2 + 2CO2 → CH3CH2OH + 3H2O
Productsmethanol, ethanol (main product), propanols, butanols, pentanols, hexanols, heptanols, methane
Production of EthanolProduction of EthanolDirect Synthesis of SyngasDirect Synthesis of SyngasProduction of EthanolProduction of EthanolDirect Synthesis of SyngasDirect Synthesis of Syngas
COMPRESSOR
COOLING
COMPRESSOR3 PARALLEL
REACTOR LOOPS3 STEAM
GENERATORS
DISENGAGEMENT VESSEL
METHANOL PRODUCT COLUMN
AZEOTROPIC DISTILLATION
COLUMN
ALCOHOL DRYING COLUMN
ETHANOL PRODUCT COLUMN
syngas
aqueous alcohols
dried alcohols
60°F127°F
870 psia 608°F
140°F 250°F
azeo
trop
e m
ixtu
re
recycled syngas
ethanol product140°F
n-propanolIso-propamol
Production of EthanolProduction of EthanolDirect Synthesis of SyngasDirect Synthesis of SyngasProduction of EthanolProduction of EthanolDirect Synthesis of SyngasDirect Synthesis of Syngas
Uses of SyngasUses of SyngasUses of SyngasUses of Syngas• generation of industrial gases, fertilizers, chemicals
• production of transportation fuels
• used as an intermediary building block for the final production of various fuels such as:
• synthetic natural gas
• methanol
• synthetic petroleum fuels (dimethyl ether – synthesized gasoline and diesel fuel)
• hydrogen component of syngas can be used to directly power hydrogen fuel cells for electricity generation
Uses of EthanolUses of EthanolUses of EthanolUses of Ethanol
• used extensively as a solvent in the manufacture of varnishes and perfumes• used as a cooking and lighting fuel• used in an antiseptic• manufacture of acetaldehyde and acetic acid• as the fluid in thermometers• a primary constituent in alcoholic beverages