Material Balance of ammonium sulphate production

MATERIAL BALANCE CALCULATIONS FOR AMMOINUM SULPHATE MANUFACTURE Chemical reactions involved for the Ammonium sulphate: NH3+H2O NH4OH +8.3 Cal/g mol------(1) mol------(1) 2NH4OH+CO2  (NH4)2CO3 +22 cal/g mol ----(2) (NH4)2CO3+CaSO4 (NH4)2SO4+CaCO3 (NH4)2SO4+CaCO3 + 3.9 cal/g mol-----(3) mol-----(3)

Molecular weights(in g/mol): NH3=17 H2O=18  NH4OH=35 CO2=44 (NH4)2CO3=96 CaSO4=136 CaCO3=100 (NH4)2SO4=132 If we require require to produce 300 tonnes of Ammonium Sulphate.And considering 24 hr operation of the Ammonium sulphate plant. Then production rate per hour is :300 tonnes=300,000kg tonnes=300,000kg Therefore,Ammonium Therefore,Ammonium Sulphate produced per hour is =300,000/24 =12,500Kg/hr 

And it has been found that the approx. 100 kgs of the Ammonium Sulphate produced is lost in filtration process. Required production rate=12,400 Kg/hr  Assumptions:Considering complete conversion in the (1) and (2) reactions and for  reaction (3) conversion is 96%.  Now the Gypsum obtained has the following composition:Gypsum composition

Gypsum= 85% Calcium Carbonate= 10.4% Insolubles=3.6% Free moisture= 1% BASIS:-1-HOUR OPERATION Gypsum required :

 Now if we consider all the reactions to take place stoichiometrically. Then from reaction (3) we have:(NH4)2CO3+CaSO4 (NH4)2SO4+CaCO3 + 3.9 cal/g mol-----(3) 136 kg

132 kg

132 kg of ammonium sulphate requires 136 kg of gypsum, So,1kg of ammonium sulphate requires 136/132= 1.03kg So, 12500 would require=12500*1.03=12875kg. As the reaction has 96% conversion and the gypsum is only 85% of  the gypsum supplied so Net gypsum required= 12875*1/0.85*1/0.96

=15,778.18 kg Ammonium carbonate required :

(NH4)2CO3+CaSO4 (NH4)2SO4+CaCO3 + 3.9 cal/g mol-----(3) 96 kg

136kg

96 kg of Ammonium carbonate requires 136 kg of gypsum So, 1 kg will require = 96/136=0.70 So, 15778.18 will require= 0.70*15778.18=11044.72kg Aqueous ammonia required:

2NH4OH+CO2  (NH4)2CO3 +22 cal/g mol ----(2) 70kg

96kg

From the reaction (2) we see that the 96 kg of ammonium carbonate requires 70 kg of ammonium hydroxide . So,11044.72 kg of ammonium carbonate would require: 70/96*11044.72=8053.44kg Ammonia required :-

 NH3+H2O NH4OH +8.3 Cal/g mol------(1) From this reaction we see that 1mole of ammonia produces ,1 mole of  ammonium hydroxide but this is only the half of the actual requirement by reaction (2) Ammonia of Aq. Ammonia produced =8053.44/2=4026.72kg Hence ,35 kg of Aq.ammonia requires 17 kg of ammonia 4026.72kg of Aq.ammonia would require: 17/35*4026.72=1955.83 kg

Carbon dioxide required:

From reaction(3) 100 kg of ammonium carbonate requires 44kg of carbon dioxide. 11,044.72 kg of ammonium carbonate would require: 44/100*11,044.72=4859.67 kg Water required :

35 kg of aq.ammonia requires 18 of water  4026.72kg of aqueous ammonia would require:18/35*4026.72=2070.88 kg

Summarising the results obtained above we have:RAW MATERIALS Gypsum Ammonium Carbonate

AMOUNT(kg/hr) 15,778.18 11044.72

Aqueous Ammonia Ammonia Carbon dioxide required

8053.44 1955.83 4859.67

Water required

2070.88