1. Ammonium Nitrate and UAN
ChE 397 – Team 7
Ammonium Nitrate and UAN
Mentor
Adam Kanyuh (UOP)
Members
Tim Brown (Team Leader)
Mahalet Sebhatu (Scribe)
Gabriel Salamanca
Rami Saigh

2. Introduction
This plant focuses on the production of Ammonia-Based fertilizers.
The plant will be located in the Williston, North Dakota
Our focus is on the production of Ammonium Nitrate (A.N.) and Urea-Ammonium Nitrate (UAN-32)
These products are valuable in the fertilizer industry due to their high levels of nitrogen.

3. Outline Ammonium Nitrate (A.N.) Urea-Ammonium Nitrate (UAN)
Design Basis
Inputs and Outputs
Environmental Review
Competing Processes
Nitrophosphate
Carnit
Stengel
Block Flow Diagram
Conclusion
Urea-Ammonium Nitrate (UAN)
Design Basis
Inputs and Outputs
Environmental Review
Block Flow Diagram
Conclusion

4. Design Basis Ammonium Nitrate Production
Based on a total output of TPD ( TPD) of NH4NO3, dry weight
Feed streams:
423.9 TPD (460.8 TPD) NH3 dry weight
TPD ( TPD) HNO3 dry weight
At 63% HNO3 by weight: TPD ( TPD)
Output streams
920.5 TPD ( TPD) NH4NO3 dry weight
Split between granular and solution streams, amounts are to be determined
TPD ( TPD) NH4NO3 dry weight
Sent to UAN process
Assumptions:
100% yield
Full separation of product from waste
Red figures based on 92% operation time
The process is extremely exothermic, producing heat in excess of it’s own required processes resulting in available heat for other processes. If the ammonium nitrate reaches 240 degree Celsius, it has the potential to blow up.
Utilities required: Steam, Electricity, Water

5. Design Basis Environmental Review: Ammonium nitrate:
Processes releasing most of emissions are the neutralizers (nitric acid, ammonia, and particulates) depending on which reactant is present in excess, but mostly ammonia.
Ammonia emission range from g/kg to 3.14 g/kg.
According to EPA, particulate emission from ammonium nitrate solutions based on an average neutralizer capacity of 131,500 metric tons/year. [3]:
Emission point
Maximum ground level concentration (μg/m3)
Neutralizer
539
Evaporator/concentrator
190
Cooler 16

6. Competing Processes I Nitrophosphate Process (a.k.a. Odda process)
Involves acidifying phosphate rock with nitric acid to produce calcium nitrate crystals, which later react with NH3 to produce ammonium nitrate.
Process uses many raw materials that aren’t supplied, so it is economically unsound to run in the plant as currently designed.
This process has an addition of Carbon and Calcium, which would be excessive to remove and extra equipment. [4]
Ca3(PO4)2 + 6 HNO H2O → 2 H3PO4 + 3 Ca(NO3) H2O
Ca(NO3)2 + 2 NH3 + CO2 + H2O → 2 NH4NO3 + CaCO3

7. Competing Processes II
Carnit Process
Two reactors are required for this process
A titanium reactor for the acidic solution
A low carbon stainless steal reactor for the alkaline solution.
Process involves boilers and a falling film evaporator made from low carbon stainless steel
Unreacted nitric acid recycles to the reactor to react with additional ammonia.
Extra steps are required to produce granular ammonium nitrate. [5]

8. Competing Processes III
Stengel process
Energy Efficient
Relatively few pieces of equipment
Recovers much of the exothermic energy and has the potential to use it in another process.
NH3(g) + HNO3 (aq)  NH4NO3 (aq) 99% yield
This is the most viable option, both feed streams can be easily provided and doesn’t produce excessive waste.

9. Process Selection [Odda]
Process uses many reactants that aren’t supplied, so it is economically unsound to run in the plant as currently designed.
This process has an addition of Carbon and Calcium, which would be excessive to remove and extra equipment. [5]
[Carnit]
Process requires extra equipment
Process is more complicated
97.5% yield
[Stengel]
Process uses reactants efficiently
Good energy recover in terms of recycled steam
Low emissions
99% Yield

10. Block Flow Diagram (A.N.)

11. Design Basis Urea-Ammonium Nitrate (UAN-32)
Based on Product steam of TPD (2590.9)
Feed Streams:
TPD ( TPD) NH4NO3 dry weight
831.3 TPD (903.6 TPD) CO(NH2)2 dry weight
687.6 TPD (747.4 TPD) H2O
May be mixed in with the two previous feeds
Product stream
TPD (2590.9) UAN-32 (solution)
UAN-32 is defined to have 32% nitrogen by weight
Assumptions
Well-Mixed
No Waste Streams
Perfect pH balance
Dry feed steams
Red figures based on 92% operation time
Utilities – Water, Electricity

12. Design Basis Environmental Review: UAN: Handling and Storage:
UAN solution is not explosive; however, it decomposes to noxious, poisonous gases when exposed to high temperature.
No gaseous emissions or waste arise during the non-pressure mixing of the aqueous based components if the best available technology is employed.
pH values and temperatures must be monitored continuously.
The ammonium/nitric acid levels are generally too small to cause a major hazard. [2]
Handling and Storage:
Avoid using zinc or copper alloys in contact with UAN solution due to corrosion. Use corrosion inhibitors to prevent corrosion. [1]

13. Block Flow Diagram (UAN)

14. Conclusion
We will use the Stengel process to manufacture A.N. on a total basis of TPD.
Also include the manufacture of UAN on a basis of TPD by a mixing process
All information presented today is a portion of our Report Outline.
Design Basis
Introduction
Enviromental concerns and standards
Process Description
Block Flow Diagrams
Flow Sheet, material and energy balances, hand calculations, and rough economics will be covered on the next presentation.

15. Thank you for your time
Questions?

16. References
[1]
[2] %20Ammonium%20Nitrate.pdf
[3] ndex=1976%20Thru%201980&Docs=&Query=&Time=&EndTime=&SearchMethod=1&TocRestr ict=n&Toc=&TocEntry=&QField=&Qfi
[4]
[5] it+Ammonium+Nitrate+Process&source=bl&ots=rWUhKgOFIn&sig=RzRctOgG8ZuFTLM M0Et2dE- jiAY&hl=en&sa=X&ei=CVoWT9X5KIKvgweCr_yhAw&ved=0CD0Q6AEwBA#v=onepage&q =Carnit%20Ammonium%20Nitrate%20Process&f=false