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Anhydrous Ammonia

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I developed this set of slides for my upper level nutrient management course.

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Anhydrous Ammonia

  1. 1. What is Anhydrous Ammonia?• “Dry” or pure ammonia – NH3• Colorless gas at room temperature and pressure• Stored as a liquid under pressure (nurse tanks rated for > 250 psi)• When pressure is released, liquid NH3 vaporizes forming an invisible highly hydrophilic gas with a very pungent odor (detectable at ~ 25 ppm)• Low levels of human exposure can result in injury and higher levels can result in death
  2. 2. Boiling point = -28F (-33.3 C) Density = 681.9 kg/m3 at −33.3 C (liquid) How does this compare with water?What is a picometer (pm)? atomic weight of N = 14 g/mol molecular weight of NH3 = 17 g/mol 14/17 = 82.3% N
  3. 3. Does NH3 dissolve in water? YES!! NH3 is polar !Solubility in water decreases with temperature 47% (0 C) 31% (25 C) 28% (50 C)
  4. 4. What does “most reduced” mean? Nitrogen has many different oxidation states ! Species Name Oxidation State NH3, NH4+ Ammonia, ammonium ion -3 Most reduced N2H4 Hydrazine -2 NH2OH Hydroxylamine -1 N2 Nitrogen 0 N2O Nitrous oxide +1 NO Nitric oxide +2 HNO2, NO2- Nitrous acid, nitrite ion +3 NO2 Nitrogen dioxide +4 HNO3, NO3- Nitric acid, nitrate ion +5 Most oxidized
  5. 5. NH3 is an important component of the N cycle! Soil NH3 Plant biomass
  6. 6. Human activities now dominate global cycling of reactive N> 150 million metric tons of NH3 synthesized in 2008
  7. 7. Ammonia is an important industrial chemical.85%Agrochemicals and Security: Security and Anhydrous Ammonia Anhyd-03
  8. 8. Industrial uses of NH3Ammonium nitrate is used to make explosives as well as nitrous oxide(laughing gas). Ammonium bicarbonate has applications in baking powderformulations, in fire extinguishers and as a blowing agent in themanufacture of polymers.Ammonia is used in the production of hexamethylenediamine for nylon,acrylonitrile for fibres and plastics, caprolactam for nylon, isocyanates forpolyurethanes, and hydrazine. It is used as a catalyst in phenol-formaldehyde condensation and in urea-formaldehyde condensation tomake synthetic resins.Ammonia is making a come-back as a refrigerant because it does notcontribute to ozone depletion and global warming when released to theatmosphere. It is said to be an efficient refrigerant in food processing andpreservation as well as other refrigeration and air conditioning processes.Other uses for ammonia include as a cleaning and bleaching agent, and ahousehold cleaner.
  9. 9. Why is NA the only region where NH3 isused directly as a fertilizer?
  10. 10. TWA = time weighted average, STEL = short-term exposure limit, IDLH = immediately dangerous to life/health Ammonia Hazards • Caustic (alkali) burns • Frost bite • Inhalation danger to lining of mouth, throat and lungs • Does not support respiration – suffocation danger • Especially dangerous to eyes TWA = 25 ppm STEL = 35 ppm IDHL = 500 ppm Agrochemicals and Security: Security and Anhydrous Ammonia Anhyd-06
  11. 11. Exposure to > 5000 ppm normally results in death Means of Exposure• Hose – rupture, not bled• Connection – faulty, worn, improperly connected, freezing• Valve – corroded, worn, or freezing• Inhalation danger to lining of mouth, throat and lungs • Tank rupture or pressure• Does not support respiration relief (Never fill tank over 85%) – suffocation danger• Very dangerous to eyes Agrochemicals and Security: Security and Anhydrous Ammonia Anhyd-07
  12. 12. Personal Protective Equipment• Always use eye and hand protection when working with anhydrous ammonia• Use full-body protection when working with large tanks Agrochemicals and Security: Security and Anhydrous Ammonia Anhyd-08
  13. 13. ResponseWater, water, water!Carry a squirt bottle on your person and in your vehicle for immediate first aid to eyes.Have a water hose installed near all storage tanks.Know the location of showers and eye wash stations. Agrochemicals and Security: Security and Anhydrous Ammonia Anhyd-09
  14. 14. Fritz Haber – a man with many faces
  15. 15. Laboratoryapparatus designed by Fritz Haber in 1909 for producing NH3 from H2 and N2. The catalytic process took placein the large cylinder on the left.
  16. 16. Part IDiscuss Sir William Crookes doomsday speech to the British Academy of Science in 1898. What washe concerned about?What happened in Germany 10 years after Crookes speech?What is Dr. Vaclav Smil’s explanation for why China decided to increase its diplomatic relations withthe US during the Nixon administration?Discuss the N budget on Bob Fry’s farm in Maryland. How much N is coming in and where is it going?The end of part I includes some comments by Dr. James Galloway who is a leading investigator of theecological impacts of N pollution. Identify 4 problems that can occur when N leaks out of agriculturalsystems into the surrounding environment.Part 2The phrase “paradox” of science is used midway through the second audio file about Fritz Haber.What is meant by this phrase? Why is Haber considered a prime example of the “paradox of science”?Briefly discuss Haber’s role in the weaponization of some of his scientific discoveries. Was he activelyinvolved? Why?What happened to Haber’s first wife?Why was Haber’s memorial service only attended by women?Why was Zyklon B developed and how was it used during WWII?
  17. 17. If you want to learn more about Fritz Haber…
  18. 18. Founded in 1865, BASF is the worlds largest chemicalcompany, ahead of Dow and DuPont, ~ 100,000 employees,> $80 billion in sales in 2007.Karl Bosch worked for BASF and designed the technologyfor upscaling Haber’s method of NH3 production.Nitrates and ammonia made up 59 percent of BASF sales in1919.
  19. 19. Haber – Bosch process development• Haber and Bosch tested > 6500 catalysts beforediscovering the high activity of iron basedcatalysts.• Modern catalysts are still closely related tooriginal ones• High pressure and temperature are needed• At temperatures lower than 400C, the reactionrate is very slow→ minimum temperature required to reach theequilibrium sufficiently fast• Typical reaction conditions:– 402C at inlet; 447 – 497C at outlet– 100 – 250 bar
  20. 20. Catalysts lower the activation energy required to react N2 with H2
  21. 21. Industrial N fixation is very energy intensive> 700 GDF/ton NH3 Large improvements in energy efficiency were made during the 20th century. ~ 300 GDF/ton NH3 ~ 185 GDF/ton NH3130 GDF/ton NH3 Theoretical minimum GDF = gal. diesel fuel Diesel fuel is not actually equivalent used to make NH3 Fig. 6.12 in Smil (2001)
  22. 22. Energy required to produce NH3 1 GJ = 6.8 gal. diesel
  23. 23. CH4 Haber-BoschN fixation Industrial process Where doesthe hydrogencome from?? http://4.bp.blogspot.com/_7RVwVtep2vE/SmrKGGhX4JI/AAAAAAAAAHI/iJUdqNU-ROg/s1600-h/haber2.gif
  24. 24. Can be usedto make urea
  25. 25. Recent
  26. 26. Nitrogen imported by the US
  27. 27. 23 facilities
  28. 28. Domestic NH3 Production in 2010Ammonia was produced by 12 companies at 24 plants in 16 States in the United States during 2010; 4 additional plants were idle for the entire year.Sixty percent of total U.S. ammonia production capacity was centered in Louisiana, Oklahoma, and Texas because of their large reserves of natural gas, the dominant domestic feedstock. In 2010, U.S. producers operated at about 85% of their rated capacity. http://minerals.usgs.gov/minerals/pubs/commodity/nitrogen/mcs-2011-nitro.pdf
  29. 29. http://minerals.usgs.gov/minerals/pubs/commodity/nitrogen/mcs-2011-nitro.pdf
  30. 30. http://minerals.usgs.gov/minerals/pubs/commodity/nitrogen/mcs-2011-nitro.pdf
  31. 31. CF Industries ** = IL terminal * * * *
  32. 32. Ammonia Distribution Network 1005 ApplicationManufactureDistribution Storage Delivery Agrochemicals and Security: Security and Anhydrous Ammonia Anhyd-04
  33. 33. Ammonia pipelines in the USThe pipelines are 8-10 inch diameter, constructed of plain carbon steel, with a total length of approximately 3000 miles.
  34. 34. Ammonia pipelinesThree companies served 11 States with 5,090 kilometers (km) of pipelines and4,800 km of river barge transport; rail and truck were used primarily for interstateor local delivery.NuStar Energy L.P. continues to operate the Gulf Central ammonia pipeline. The3,200-km ammonia pipeline originated in the Louisiana Delta area, where it hadaccess to three marine terminals and three anhydrous ammonia plants on theMississippi River. The capacity of this pipeline was about 2 million metric tons peryear (Mt/yr) of ammonia, with a storage capacity of more than 1 Mt. In 2008,about 1.5 Mt of ammonia was shipped through the Gulf Central ammoniapipeline.On June 1 2010, Magellan Midstream Partners, L.P. assumed operations of itsammonia pipeline from a third-party pipeline company. The 1,750-km pipelinesystem, which transported and distributed ammonia from production facilities inOklahoma and Texas to various distribution plants in the Midwest, had a deliverycapacity of about 820,000 t/yr. In 2008, 746,000 t of ammonia was shippedthrough Magellan’s pipeline compared with 650,000 t in 2007. http://minerals.usgs.gov/minerals/pubs/commodity/nitrogen/mcs-2011-nitro.pdf
  35. 35. Main concepts in the article 12 anhydrous terminals in Illinois Most are supplied by barge or pipeline Only one terminal is supplied by rail The pipeline is currently at capacity Terminals were built in the late 60s and early 70s. Rail carriers have petitioned for indemnificationRetailers have expressed interest in receiving NH3 directly by rail Fall applications are necessary
  36. 36. N fertilizer materials (tons) purchased in IL Material fall06 spring07MAP 11-52-0 6,955 4,017 10.5%DAP 18-46-0 56,653 42,147 10-34-0* 766 1,567 28-0-0 19,173 127,447UAN 22.5% 32-0-0 12,616 75,737Urea 46-0-0 10,136 23,480 3.2%AA 82-0-0 293,375 277,952 55 % 82.5-0-0 17,906 4830 98.8 % of material grade 1,043,307 94.6% of total N * (10-30-0, 10-32-0, 10-34-0, 11-33-0, 11-37-0)
  37. 37. Shift toward greater use of urea and UAN in the Midwest
  38. 38. Reasons for the decline in use of AA Concerns about human safety Concerns about impacts on soil (little research evidence) Rail companies are raising rates and limiting transport of NH3 Weather/soil conditions limit NH3 application window UAN application is faster and more flexible(1-2 thousand acre/day for UAN vs. a few hundred acres for NH3) UAN can be applied with other crop inputs
  39. 39. What do farmers think about anhydrous? Anyone know this guy?
  40. 40. Tom Oswald wrote:It is our preferred source of N for a number of reasons. My Dad remembersgoing to ammonia meetings back in the late 1950s-1960s and the optimumsdiscussed at those meetings are still the same though we stretch into fallapplication as part of strip till and earlier corn planting than in years past.1- N is at depth. In the sometimes dry western corn belt, this is a good thing.In 2007, my sidedress liquid N plots were 20 bu/ac less than fall+ planter 20#.Rain stopped right after sidedressing. and the corn suffered.2- N is banded..... a good thing.... concentrated in less soil volume. Unlikesprayed on 28% or broadcast urea which is a horizontal band.3- Concentrated form of N, less gallons handled.4- Some suggest ammonium form better for corn. (Charles Tai, Purdue,1980s I think)5 "Here" pipelines and tankers handle most of it.6- Have my own toolbars and controllers (can be used for both liquid orammonia, strip or sidedress).7- Manly way to farm (big tractors, lots of iron, dangerous)8- Believe that compaction (runway construction etc) is mostly a myth. Tillageis harder on the soil than ammonia.9- liming behind ammonia not that much worse. Ammonium sulfate is worse Ibelieve. Talk to a soil chemist.
  41. 41. Cons:1- Manly way to farm (big tractors, lots of iron, dangerous)2- Theft3- Environmentalists target ammonia tanks in their advertising4- requires soil incorporation (tillage via knife)5- control equipment is expensive6- gassing can burn emerged crop if done improperlyIn summary, we (Dad and I) like AA and hope to keep using it as the primaryN source on our farm. I think the benefits outweigh the negatives andbelieve that our yields would be somewhat lower (on average over theyears) and our costs would be higher if we had to switch to urea or liquids.We hope that the regulators and nitrogen production companies dont take itaway.Tom-----Thomas E. OswaldOswald Family FarmCleghorn Iowa
  42. 42. Unusually high
  43. 43. http://www.ipm.iastate.edu/ipm/icm/node/181/print
  44. 44. Maximum soil temps under bare soils at 4”http://www.isws.illinois.edu/warm/ DOof I anhydrous U NOT APPLY application guidelines are basedYOUR WHEN on daily maximumIS RED! AREA temp at 4”Fall N application south of IL HWY 16 is never recommended by the U of I
  45. 45. “If the industry is tocontinue the practice of fall N application, wemust police ourselves orrisk being regulated by federal government agencies and lose the ability to apply fall nitrogen.”
  46. 46. Being smart about the timing of anhydrous application canpay large dividends!Wait until soil temperatures at the 4-inch depth are below50 degrees Fahrenheit.The rate of nitrification is significantly reduced when soiltemperature is below 50 degrees F, but microbial activitycontinues until temperatures are below freezing.In order to minimize risk, don’t apply nitrogen before the thirdweek of October in central Illinois, or the second week innorthern Illinois, even if air temperatures are getting cooler.In addition, do not use nitrogen or nitrogen with a nitrificationinhibitor if you live south of Illinois Route 16 or if soils areprone to leaching.
  47. 47. Nitrification inhibitors are not 100% effectiveand are only cost-effective in some situations Sample Date Dec. 8 Apr. 2 May 3 Application N-serve % NH4-N Remaining No 39 19 3 Nov. 7 (>50°F) Yes 63 28 17 No 40 33 7 Nov. 18 (<50°F) Yes 67 58 26 http://www.ipm.iastate.edu/ipm/icm/2001/10-22-2001/why50.html
  48. 48. It is normally more efficient to apply N in the spring even if a nitrification inhibitor is used Spring w/o N serve Fall with N serve Fall without N serve
  49. 49. Impact of pH and N-serve on % nitrification Inhibitor = N-Serve w/o N serve w/ N serve% Nitrification High ph inhibits nitrification as Low ph can override N-serve much or more than N-serve Soil pH http://soil.scijournals.org/cgi/content/full/68/2/545/FIG4
  50. 50. Soil pH should be considered an important factor affecting the risks and benefits associated with fall applications of anhydrousammonia under climatic conditions found in the Corn Belt.Relatively rapid nitrification in higher-pH soils increases the potential for early season losses of fertilizer N byleaching and denitrification of NO–3 before plants begin rapid growth and uptake of N.N-Serve is probably a waste of money on low pH soils!
  51. 51. So what do you think of the rule of thumb – 10 lbs of NH3-N per unit of CEC? This may be one of the worst and misguided soil fertility concepts that I have heard (OK, ranks up there). I am not going to do the CEC math, but I think Joel has a decimal point or unit charge off somewhere. What is missing from his explanation is the fact that ammonia interacts with the soil organic matter and soil clays (beyond negative charges). Soil moisture helps retain and limit ammonia movement at injection time, but it is all of the soil properties that result in a small retention zone. Take a look at Joe Touchtons publications (and go way back in time to McIntosh and Frederick -- 1950s) and you will see the small size of an ammonia retention zone, even in "low" organic matter and "low" CEC soils. So, it is much more than CEC alone that influences ammonia retention.
  52. 52. What rate is this in lbs/ac? 8.4 g N/m in Kahola siltloam Izaurralde et al. (1987)
  53. 53. If uniformly distributed in a 2 million lb/ac plow layer, 1000 ppm N = 2000 lbs of N/acSoils can clearly retain a lot more N than 10 lbs * CEC!
  54. 54. In the retention zone, 33% of the CEC is saturated with NH4+
  55. 55. Many anhydrous ammonia applicators give uneven applications, particularly applicators with older manifolds. Manifold outlets across from the intake usually put out higher rates than outlets near the intake.When an older manifold is used, the most importantmanagement practice is to randomize the hoses. Thismeans that a row getting a low rate is more likely to be next to a row getting a high rate, which will minimize yield loss.
  56. 56. http://www.extension.iastate.edu/Publications/PM1875.pdf
  57. 57. How Equaply® WorksAccurate control of mixed gas and liquid phases is difficult toachieve. Conventional application systems do an excellentjob of applying consistent amounts of anhydrous ammoniaover a field. But they dont provide equal flow to each injectorknife. Heat exchangers cool the ammonia below its boilingpoint before entering a flow meter and control valve. Withonly liquid present, the valve can exert near perfect control.However, when the anhydrous goes through the control valveit loses pressure and boils, creating a mixture of liquid andgas. This mixture is difficult to be split evenly in a manifold.So distribution among the knives is random and variable. http://www.anh3.com/about%20anh3.html
  58. 58. http://www.bcsclients.com/email/jd/20080807/08/index.html
  59. 59. Shallow placement of anhydrousTraditional thinking is that anhydrous ammonia must be placed 8 in. deep inthe soil. The 2510H High Speed Applicator places anhydrous at 4.5-in. depth,which is quite a difference from traditional thinking.John Deere has tested this placement across the Corn Belt in real-world fieldapplications and plot-size treatments. More than 10,000 acres of spring pre-plant anhydrous ammonia application yielded no reports of seedling damage.To further evaluate shallow placement, plot-scale studies were initiated withthree university cooperators that put the concept to the test by planting rightover the anhydrous application track seven days after application.To avoid seedling damage with the 2510H, the same recommendations applyas when using a conventional shank applicator: * Allow a window of opportunity * Apply to the rows at an angle * Soil moisture conditions http://salesmanual.deere.com/sales/salesmanual/en_NA/primary_tillage/2010/feature/nutrient_applicator/2510h_shallow_placement.html
  60. 60. Retention at a shallow depth What about retention at a shallow depth? John Deere has gone to great lengths to verify the anhydrous retention provided by a 2510H is equal to that of a shank. Three methods were used to measure retention. The brick soil sampling method entailed extracting a brick of soil in the injection zone 24 hours after application and send it off to a lab for analysis. A side-by-side comparison of the 2510H with a conventional shank revealed equal retention. The other two methods were the litmus paper test and the chamber technique to collect emissions. All three methods revealed equal retention with a shank applicator.http://salesmanual.deere.com/sales/salesmanual/en_NA/primary_tillage/2010/feature/nutrient_applicator/2510h_shallow_placement.html
  61. 61. http://www.youtube.com/watch?v=8xpBd1cI_6Y
  62. 62. http://nebraskafarmer.com/story.aspx/anhydrous/hookup/offers/no/hands/convenience/30914
  63. 63. http://www.youtube.com/watch?v=L4FsvwKT70g
  64. 64. Standard (24 steps) PitStop Pro (10 steps) 1) NH3 Application 1) NH3 Application 2) Tank goes empty 2) Tank goes empty3) Operator moves tractor, applicator, and empty tank to end 3) Operator moves tractor, applicator, and empty tank to end of of field or full tank location field or full tank location 4) Operator exits tractor 4) Operator presses Detach Hose button in cab 5) Operator outfits PPE while approaching rear of applicator 5) Operator presses Detach Hitch button in cab 6) Operator closes tank supply valve 6) Operator moves tractor/applicator to full tank 7) Operator closes supply hose valve 7) Operator backs applicator up for attachment to full tank 8) Operator opens bleeder on supply hose 8) After contacting full tank with implement hitch, operator pulls forward to confirm attachment9) Operator waits while NH3 bleeds out between tank shutoff 9) Operator presses “Attach Hose” button in cab valve and supply hose shutoff valve 10) Operator removes supply hose from tank 10) Operator returns to location and begins to apply NH3 11) Operator climbs down from tank with supply hose and places on rear of applicator 12) Operator pulls out drawbar pin 13) Operator returns to tractor cab 14) Operator removes PPE while walking to tractor 15) Operator moves tractor/applicator to full tank 16) Operator backs applicator up for attachment to full tank17) Operator exits tractor and returns to rear of applicator to attach drawbar of tank to applicator 18) Operator pulls out applicator adjustable rear hitch, lifts tank drawbar and attaches with pin 19) Operator outfits with PPE20) Operator places supply hose on tank then climbs up tank 21) Operator attaches NH3 supply hose to tank 22) Operator opens both supply hose valve and tank valve 23) Operator returns to tractor 24) Operator returns to location and begins to apply NH3 Green = tractor in motion
  65. 65. Does NH3 really have potential as a fuel? • Ammonia (NH3) can be produced from any raw energy source, including all fossil, renewable and nuclear sources. • Ammonia is cost competitive with gasoline as a transportation fuel (need to check on this) • Ammonia has extensive, worldwide transportation and storage infrastructure already in place • Ammonia is very environmentally friendly when used as a transportation fuel and produces only N2 and H20 at the tailpipe with low-cost emissions controls. • Ammonia has been successfully demonstrated in SI engines, CI engines, and fuel cells.