This document provides information about NFL, one of India's largest producers of nitrogenous fertilizers. It details NFL's production processes and facilities, including its use of natural gas as a feedstock. NFL operates four urea production lines with a total daily production capacity of 6,261 tons. The document discusses the chemical reactions involved in urea synthesis, key parameters that affect the reactions such as temperature, pressure and residence time, and specifications for different categories of urea produced.

2. Introduction about NFL
 NFL is one of the largest contributor of nitrogenous fertilizer in the
country. It was started on 23 august 1974.
 It is the first company to be permitted by Govt. of india to produce
and market neem coated urea.
The company is also carrying out research and development activities
in zincated and sulphur coated urea.
NFL feedstock is natural gas.

3.  Waste heat reboiler
 CPP(captive power plant)
 DM water plant
 Line 1 ammonia
line 2 ammonia
line 1 urea
line 2 urea
UNITS

4. Capacity of Plant
 Line 1: 11 stream = 1515 tpd
21 stream = 1515 tpd
 Line 2: 31 stream = 1615 tpd
41 stream = 1615 tpd
 Total production = line 1 + line 2 = 6261 tpd
 Each bag is filled up by 50 kg of urea

5. UREA
 Molecular weight = 60.06
 Melting Point =132.7 degrees
 Density = 1.3335 g/cm3
 Bulk density:
Prilled =740 g/cm3
Granular=720-770 g/cm3
Raw material
 Ammonia (liquid)
 Carbondioxide(gas)

6. Reactions Involved
2NH3 liq + CO2gas NH2 COONH4
(ammonium carbonate)
+37.4 kcals/kg moles
NH2COONH4 NH2CONH2+H2O
(urea) (water)
-6.32 kcals/kg moles

7. NH2COONH4 2NH3 + CO2
NH2COONH4+H2O NH3+CO2+H2O
NH2CONH2+H2O 2NH3+CO2
(hydrolysis)
2NH2CONH2 NH2CONHCONH2+H2O
(Biuret)
Side Reaction

8. PARAMTERS AFFECTING UREA
SYNTHESIS REACTION
Temperature
 Low temp favors reaction 1.
 High temp favors reaction 2.
 Increasing the temp proportionally increases the conversion.
 Maximum equilibrium conversion around 190-200°C
 Higher temperature leads to corrosion

9. PRESSURE
 Higher pressure favors urea formation.
 Pressure has to be higher than the dissociation pressure
corresponding to the reactor temp.
 Pressure depends on the selected synthesis temp.
 The equilibrium pressure becomes higher & higher when the
temperature increases

10. RESIDENCE TIME(RT)
 High RT: Higher conversion.
 Min. RT to attain equilibrium: 20 min.Higher RT can compensate
other unfavorable conditions
 NH3/CO2=4.0,Temp= 188°C, RT=30min--- Conversion=68%
 NH3/CO2=2.8,Temp= 181°C, RT=55min--- Conversion=61%
 Higher RT increases capital cost

11. PFD

12. Categories of Urea
 Agriculture urea.
1. N2 > 46% minimum
2. H20 < 1% maximum
3. biuret < 1.5% maximum
4. Prills size : urea should pass through 2.8mm sieve
 Technical urea.
1. N2 > 46% minimum
2. H20 < 0.5% maximum
3. biuret < 0.8% maximum
4. Prills size : urea should pass through 2.0mm sieve
 coated urea.
1. Same as Agriculture urea , prills is coated with neem powder.

13. Technical Agriculture Neem
urea urea coated

14. Specifications for Prilling tower
Airflow through Prilling tower is 12000 Nm3/ton
PRILL SIZE PRILLING
TOWER
1. 2mm
2. 3mm
3. 4mm
90 meters
150 meters
220 meters

15. FACTORS AFFECTING PRILLS
QUALITY
Sr.No. FACTORS EFFECTS
1. High moisture content Caking tendency
Dust formation
2. Draft (poor) High prill temperature
Dust formation
3. Bucket condition(poor) Irregular particle
Dust formation
4. High melt temperature High biuret content
High free NH3

16. CONCLUSIONS
 Policies:
Environment policy(ISO-14001)
Quality policy (ISO-9001)
Energy policy
Health and safety policy(ISO-9001)
 Products:
Kisan Urea , HNO3 , NH4NO3 , NaNO3 , Sulphur,
Menthol, N2 etc.
 Bio Fertilizer Plant:
PSB, Rhizobium, Azotobacters