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Improved Nitric Acid Production via Cobalt Oxide Catalysis for use in Ammonia-based Fertilizers
University of Illinois at ChicagoDepartment of Chemical Engineering
CHE 397 Senior Design IIApril 24, 2012
Mentor: Bill Keesom
Thomas Calabrese (Team Leader)Cory Listner
Hakan SomuncuDavid SonnaKelly Zenger
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Today’s Agenda Recap of Questions from the Previous Meeting Project Overview Design Basis Block Flow Diagram Process Flow Diagram Catalyst Choice Environmental Issues Review Economics Process Safety Review Report
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Project Overview• The nitric acid plant will be located in the Bakken Formation
of the Williston Basin, located in Northwest North Dakota.• Over 1.85 trillion cubic feet natural gas
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Wellhead gas will be purified by the Gas Purification Team and sent to the Ammonia Team.
Ammonia Team will produce ammonia and send it to the Nitric Acid Team.
Nitric Acid Team will convert ammonia to nitric acid. Nitric acid will be sent to Ammonium Nitrate Team
Project Overview
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Design Basis Produce 3,289 TPD of 63% wt. nitric acid solution (~14M)
Starting Reagents Ammonia (NH3) – 571.5 TPD Air – 10,332 TPD
Products 63% wt. Nitric Acid Solution (HNO3) - 3,289 TPD Steam (1,250 psi, 970F) – 1,843 TPD
Environmental Concerns Oxides of Nitrogen (NOx) (<200 ppm) Nitrous Oxide (N2O) (<200 ppm)
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Ostwald Process Industry Standard for Nitric Acid Production
Ammonia Oxidation Nitrogen Monoxide Oxidation Absorption of Nitrogen Dioxide with Water
Primary Chemical Reactions Oxidation of Ammonia to Nitrogen Monoxide
4NH3 (g) + 5O2 (g) 4NO (g) + 6H2O (g) Oxidation of Nitrogen Monoxide to Nitrogen Dioxide
2NO (g) + O2 (g) 2NO2 (g) Reaction of Nitrogen Dioxide to Nitric Acid
2NO2 (g) + O2 (g) + 2H2O (l) 4HNO3 (aq)
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Block Flow Diagram
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Process Flow Diagram
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Platinum-Rhodium Cobalt Oxide (Co3O4)
Cost ($/short ton of HNO3 produced)
$3 - $4 $0.50 - $0.75
Lifespan 3-4 months 12 months
Downtime 4 hours to replace gauze at end of lifespan
Remove Rhodium Oxide buildup (every 3-4 weeks)
None
Conversion Efficiency
93% - 96% 95% - 98%
Operating Parameters
24-95 psi, 1490-1724 °F 0-95 psi, 1549 °F
Use Very common, industry standard
New, commercial use
Drawbacks Cost, lifespan, and greater N2O formation
New reactor design, deactivation to CoO
Benefits of Cobalt Oxide
Controlling N2O Release Primary Methods-reduce N2O 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 N2O formed immediately after ammonia oxidation (Selective Catalytic Reduction) Up to 90% efficiency Secondary catalyst is used to promote N2O decomposition by increasing the
residence time in the ammonia burner 2N2O (g) 2N2 (g) + O2 (g)
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Controlling N2O Release
Tertiary Methods-reduce N2O from or to the tail gas (Non-Selective Catalytic Reduction) 80-98+% efficiency A reagent fuel (e.g. H2 from an ammonia plant purge) is
used over a catalyst to produce N2 and water Alternatively, following SCR the tail gas is mixed with
ammonia and reacts over a second catalyst bed to give N2 and water
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Economics: Materials
MaterialsMaterial Requirement Base Cost Total Cost [per year]
Air 10,344 TPD $0.00/ton $0.00
Ammonia Vapor 571.5 TPD $350/ton $73,009,125
Nitric Acid* (SOLD) 2,571.2 TPD $220/ton $206,467,360
Nitric Acid** (SOLD) 717.8 TPD $300/ton $78,599,100
Steam (SOLD) 1,843 TPD $20/ton $13,451,491
Cobalt Oxide Catalyst - $0.50/ton acid $476,454
TOTAL + $225,000,000/year
*Sold to Ammonium Nitrate, **Sold to Open Market
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ICARUS Yearly Operating CostsItem Cost
Operating Labor $640,000Maintenance $905,000Supervision $200,000Operating Charges $230,000Plant Overhead $912,000Utilities $9,500,000TOTAL -$13,000,000/year
ICARUS Installed CostsItem Cost
Equipment (Installed Cost) $329,370,000Piping $1,900,000Civil $530,000Steel $100,000Instrumentation $1,000,000Electrical $2,500,000Paint $100,000Other $4,500,000G&A Overheads $1,000,000Contingencies $7,000,000TOTAL CAPITAL COST $348,000,000
Economics: ICARUS
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Economics: NPV
• Payback Period: 7 years• Expected Plant Life: 20 years• Interest Rate: 8%• Inflation Rate: 3%• Installation Time: 3 years• Installation Cost: $348 million• Net Present Value after 20 years: $984 million• Internal Rate of Return: 23.98%
Yearly Profit
Item Cost
Materials +$225,032,372
Operation & Maintenance -$2,900,000
Utilities -$9,535,283
TOTAL Est. Profit: $213,000,000/year
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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
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Process Safety IIOther 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
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Completed Report Open Report www.che397-nitric-acid.wikispaces.com
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Summary Recap of Questions from the Previous Meeting Project Overview Design Basis Block Flow Diagram Process Flow Diagram Catalyst Choice Environmental Issues Review Economics Process Safety Review Report
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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. <http://www.epa.gov/nsr/ghgdocs/nitricacid.pdf>.
Best Available Techniques for Pollution Prevention and Control in the European Fertilizer Industry, Production of Nitric Acid. EFMA. 2000. <http://www.efma.org/PRODUCT-STEWARDSHIP-PROGRAM-10/images/EFMABATNIT.pdf>.
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Questions?