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