1. 1 Improved Nitric Acid Production via Cobalt Oxide Catalysis for use in Ammonia-based Fertilizers University of Illinois at Chicago Department of Chemical Engineering CHE 397 Senior Design II April 12, 2012 Thomas Calabrese (Team Leader) Cory Listner (Scribe) Hakan Somuncu David Sonna Kelly Zenger

2. 2 Today’s Agenda  Recap of Questions from the Previous Meeting  Process Flow Diagram  Conceptual Control Scheme  Ammonia Oxidation  NO Oxidation  Absorption  Economic Analysis  General Plant Layout  Environmental Issues  Process Safety  Report Progress  References

3. 3 Revisiting Last Session’s Questions Sizing of absorption column  30 Trays (Sieve Trays)  D = 9 ft.  Height = 70 ft.  Material of construction = SS304L  Feed stream (NO2 (g)) = Stage #1  Feed stream (Make-up water) = Stage #30  Feed Stream (Weak acid) = Stage #25 Two heat exchangers incorrectly sized  Streams matched again for proper sizing

4. KG TOWER ® Results 4 Absorption Column

5. 5 Process Flow Diagram

6. 6 Control Scheme: NH 3 Oxidation

7. 7 Control Scheme: NO Oxidation

8. 8 Control Scheme: Absorption

9. 9 Revised Economics Payback Period: 12 years Expected Plant Life: 20 years Installation Time: 3 years Installation Cost: $418 million Net Present Value after 20 years: $530 million Excel sheet

10. 10 General Plant Layout

11. Controlling N 2 O Release Primary Methods-reduce N 2 O formed during ammonia oxidation  70-85% efficiency  Add an “empty” reaction chamber between the catalyst bed and the first heat exchanger (increase residence time)  Modify the catalyst used during the ammonia oxidation Secondary Methods-reduce N 2 O formed immediately after ammonia oxidation (Selective Catalytic Reduction)  Up to 90% efficiency  Secondary catalyst is used to promote N 2 O decomposition by increasing the residence time in the ammonia burner  2N 2 O (g)  2N 2 (g) + O 2 (g) 11

12. 12 Controlling N 2 O Release Tertiary Methods-reduce N 2 O from or to the tail gas (Non-Selective Catalytic Reduction)  80-98+% efficiency  A reagent fuel (e.g. H 2 from an ammonia plant purge) is used over a catalyst to produce N 2 and water  Alternatively, following SCR the tail gas is mixed with ammonia and reacts over a second catalyst bed to give N 2 and water

13. 13 Process Safety I  Large release of process chemicals due to catastrophic failure  Be prepared, emergency procedure with LECP  Prevention of release & associated problems :  Neutralizing materials  Initial construction of components  Release valves  Bunding, dikes  Ventilation  Fireproofing  Low release of process chemicals  Caused by operator error, poor maintenance

14. 14 Process Safety II Other Safety Precautions Long-term exposure  Maintain PEL and STEL as dictated by OSHA Noise  Governed by OSHA, PEL of 90 dB  Maintain & lubricate equipment, sound barriers, limiting exposure General protection  Insulate or guard heated surfaces on working floor  Good lighting  Railings & non-slip surfaces  Training, safety checklists

15. 15 Report Progress Open Report www.che397-nitric-acid.wikispaces.com

16. 16 References Parkinson, Richard. UOP. Where Does It Go? An Introduction to the Placement of Process Equipment. 2009. Available and Emerging Technologies for Reducing Greenhouse Gas Emissions from the Nitric Acid Production Industry. U.S. Environmental Protection Agency. 2010.. Best Available Techniques for Pollution Prevention and Control in the European Fertilizer Industry, Production of Nitric Acid. EFMA. 2000..

17. 17 Questions?