Solvay Process

Jonathan Bauer

Keith Sager

Uche Onyewuenyi

Lam Nguyen

Background

Developed by Ernest Solvay in the 1860s

Worldwide production in 2005 was 42 billion kilograms

Equivalent to 13 lbs per person per year

Raw materials are salt brine and limestone from mines

In 1884 the Solvay Brothers (Ernest and Alfred) created a joint venture to in the United States called the Solvay Process Company

There are no more solvay processing plants in North America

Natural deposits of trona (Na3(CO3)(HCO3)·2H2O) are cheaper

Applications of Soda Ash

Glass making

Soda-lime glass

Cheaper, can be re-softened and re-melted

Good for recycling

Soap and Detergent

Cheaper alternative to lye (NaOH)

Common alkali in many chemical factories

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Kiln

Temperature = 950 – 1100°CCaCO3

CaOCO2

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Ammonia Absorber

No reaction takes place

Ammonia mixes with brine

Mushroom shape baffles

Controls flow of brine for proper mixing and saturation

Brine

NH3

Ammonia and Brine

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Solvay Tower

Temperature is 0°C

Mushroom baffle plates

Breaks up CO2

Controls flow through tower

Lower part of tower is cooled because reaction is exothermic

Vacuum filter at tower bottom

NH4Cl

NaHCO3

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Water Bed

Calcium oxide comes from kiln

Calcium hydroxide is sent to ammonia recovery tower

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Ammonia Recovery Tower

Overall reaction for water bed and recovery tower

CaCl2 and H2O fall out bottom of tower

Temperature is 100°C

Ca(OH)2

NH4ClNH3

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Heater (Calcifier)

Rotary heater at 300°C

Carbon dioxide is recirculated with kiln product and sent to solvay tower

Final product is recovered as a solid

NaHCO3

Na2CO3

CO2

BRINE

CO2

CaCO3

NaH

CO3

Na2CO3

CaONH4Cl

NH

3

AMMONIA BRINE

Ca(OH

)2

AMMONIA ABSORBER SOLVAY

TOWER

KILN

WATER BED

AMMONIA RECOVERY

TOWERHEATER

Chemical Reactions Summary

Thermodynamics

Overall Process

Reaction 1

Reaction 2

Reaction 3

Reaction 4

Questions?

References

http://en.wikipedia.org/wiki/Solvay_process

http://en.wikipedia.org/wiki/Soda_lime_glass

http://en.wikipedia.org/wiki/Trona

http://www.citycollegiate.com/sblock2.htm

http://scifun.chem.wisc.edu/chemweek/PDF/Sodium_Bicarbonate_&_Sodium_Carbonate.pdf