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TRANSCRIPT
Creating Designer Manure: Technology to Control Phosphorus
Jactone Arogo Ogejo Midwest Manure Summit
March 24-25, 2009March 24 25, 2009Lambeau Field,
Green Bay, Wisconsin
Outline
• Acknowledgementso Disclaimer
• What we know about P
• Methods to remove P
• Case studies
• Discussion
Acknowledgements
Sources of information:1. Vic Johnson; Sales Manager, Agricultural and Environmental
Services; Kemira Water Solutions; [email protected]. Tim Rensch; Vice President, Integrity Agricultural Systems;
trensch@integrityagsystems [email protected]. AWS Final Report to Farm Pilot Project Coordination,
Inc
Some pictures used in this presentation are from these sources and may not be acknowledged directly on the image
Disclaimer
Use of names of companies, organizations, equipment, chemicals e.t.c. is not an endorsement or advertisement endorsement or advertisement
We know that ….
Dairy cows need P for:Growth (bone mineralization)Milk production
Energy and maintenance
We know that ….• Livestock use P in feed inefficiently
60 to 80% - Excreted
• Dairy cows are generally fed 20 to 25 % more P than recommended
Majority of P brought on farm as feed stays on Majority of P brought on farm as feed stays on the farm
• Improved feed management can reduce manure P and N without negatively impacting herd health, reproduction, or milk
We know that ….
• Manure is a good source of (N, P, & K) and that …
►Nutrients N and P do a good job growing plants in both land and water
• Manure managed properly minimizes negative impacts to the quality of the environment
► Water , Air, Soil
We know that ….Manure is typically land applied to supply nutrients (N, P, K) for crop growth
► N and P not in right proportions relative to crop needs
► Manure application based on crop N needsMay result in over-application of P
► Manure application based on crop P needsMay result in over-application of PLarger land area for manure application
We know that ….
For sustainable agriculture and continued use of manure as a fertilizer, there is a NEED to balance manure N and P to match crop needsmatch crop needs
…… and so, Designer Manure!
What is Designer Manures?The art of removing and/or distributing manure nutrients in the liquid, sludge, and solid phases in compositions to meet compositions to meet the intended needs e.g. crop fertilizer(Knowlton, Arogo, et al.)
Methods to manage manure P ….• Feed
• Physical: Separators (Screens, Mechanical, Centrifuges)
• Chemical: Metal salts – Aluminum, Iron, C l i P lCalcium; Polymers
• Biological: Enhanced biological P removal or Luxury uptake of P; Aquatic plants – algae
• Combination: Physical and Chemical; Biological and Chemical
Managing manure P: Forms of P
Total P
Ortho-P Organic-P Polyphosphates
• Ortho P: is the inorganic soluble component; takes part in most chemical reactions; biologically available
• Organic P: can be converted to ortho-P or polyphosphate
• Polyphosphates: Condensed forms or ortho-P and can be used in chemical and biological reactions
Methods to Remove P ….• Physical
Separators (Screens, Mechanical, Centrifuges)
• ChemicalMetal salts – Aluminum, Iron, CalciumPolymersPolymers
• BiologicalEnhanced biological P removal or Luxury uptake of P
• CombinationPhysical and ChemicalBiological and Chemical
Creating Designer Manure: Chem 101 ….
Aluminum Calcium
Phosphate
Chemical P removal: Based on the principle of “OPPOSITES ATTRACT”
Iron Polymers
p
Creating Designer Manure: Chem 101 ….
Chemical Formula Molecular Weight(g/mole)
Aluminum sulfate (alum) Al2(SO4)3.14H2O 594Aluminum chloride AlCl3 133 5
Commonly used chemicals (Coagulants)
Aluminum chloride AlCl3 133.5Ferric chloride FeCl3 162.2Ferric sulfate Fe2(SO4)3.9H2O 562Calcium hydroxide (lime) Ca(OH)2 74.1
Reaction: Metal Salt Ortho-P Metal Phosphate
Creating Designer Manure: Chem 101 ….
• Charge (positive or cationic, negative or anionic) • Molecular Weight (high, medium, low)
Polymers (Flocculants)
B id iBridging
Chem 101: How much Chemical?
• Depends on nutrient reduction required
Step 1
A little bit science … a little bit art
q• Depends on what else is in
manure that puts demand on the chemical
• Conduct a bench scale test to determine the chemical dose
Collect sample of manure to treat
Chem 101: How much Chemical?
Step 2:Apply different chemical doses
Step 3:Select desired chemical combination for the desired removal
Where to add Chemical and Polymers• Before solids separation• After solids separation• After anaerobic digestion
Barn
Separator
Treatment(anaerobic aerobic)
Chemical Polymer
(anaerobic, aerobic)
Separator/ Clarifier
Storage
Separate Chemically Bound Phosphorus
Screening
Band Press Separators
g
Screw Press
Case Study I: Kemira 812
• On dairy farms in Pennsylvania and Idaho
• Uses a combination of chemicals (alum, ferric chloride; ferric sulfate) and polymer
• Separator – Belt Filter and Screw Press
Case Study I: Kemira 812 – The Process Flow
1. Chopper 4. Mixer 7. Stirrer 10 & 11. Liquid manure2. Feed pump 5. Polymer 8. Belt Filter 12. Screw press3. Coagulant 6. Polymer blender 9. Pump 13. Solids
Case Study I: Kemira 812 – The Process
• Manure < 8% total solids• Separate 10,000 tons slurry
per year @ 15-17 hrs/weekS it bl f f > 500• Suitable for farms > 500 cows
• Mobile or stationary
Case Study I: Kemira 812 – The Process
• 0.7 kwh/265 gal liquid treated• Polymer and chemical quantity
based on nutrient reduction required
• 50 99% P in solid stream• 50 – 99% P in solid stream• 1 – 50% P in liquid stream• Not very efficient in sand systems• Economics may make more sense
with > 1,000 cows (Tim Rensch –Integrity Ag Systems)
Case Study II: AWS Belt Press
• On dairy farms in Georgia, New York, and Vermont
• Used belt press with polymer and polymer + Iron chloride
• GA and VT: Raw scrapped manuremanure
• NY: Anaerobic digester effluent
• Single belt press: NY & VT• Two stage belt press: GA
Case Study II: AWS Belt Press
Parameter Scraped Raw Digested ManureTS (%) 15.5 7.3
TP (mg/L) 480 580
Manure Characteristics
TKN (mg/L) 3,940 4,120TAN (mg/L) 1,900 2,420
Case Study II: AWS Belt Press
Parameter Scraped Raw Digested Manure1-Stage no
polymer1-Stage + polymer
2-stage no polymer
1-Stage no polymer
1-Stage + polymer
Solids 60 80 99 7 36 75
Solids and nutrient capture (%)
Solids 60 80 99.7 36 75
Total P 25 79 - 28 93
N (TKN) 25 71 - 13 61
Case Study III: Batch Chem Application - VT
11
2 34
5
6 7
89
urce
: Dr.
M. B
arne
s
1. Flush Tanks 2. Reception pit3. Separator
4. Storage shed for separated solids and composting
5. Settling basin
6. Tank 17. Tank 28. Tank 39. Pump house
3
Sou
Case Study III: Batch Chem Application - VT
Determined the quantity of chemical needed for 600,000 gal
Before Chemical Treatment
• Mixed for about 30 min. before chemicals applied
Chemical and Polymer Delivery
• Full strength Superfloc 4512 in tote
• Quantity – Total 275 gal.
• Bulk aluminum chloride (AlCl3) solution
• Quantity – 1,200 gal.• Strength – 28%
Quantity Total 275 gal.
• Discharged directly into manure tank
• 1,200 gal discharged in
Applying Aluminum Chloride (AlCl3)
approximately 10 min.• Mixing continued as aluminum
chloride was applied
Applying Polymer – Superfloc 4512
• About 85 gal applied after AlCl3• Used a P-6100T variable speed chemical
metering pump for about 30 min. but delivery was too slow
Tried mixing polymer with water and then dumping into tank but method was too slow and messy
Applying Polymer – Superfloc 4512
Applying Polymer – Superfloc 4512
Finally – resorted to dumping directly into tank using buckets
Mixing during AlCl3 and Polymer addition
• Used PTO pump to mix from the surface and 6 ft. from the bottom of tank
Scum, sludge, flocculation during AlCl3 addition Scum, sludge, flocculation at the end of Polymer addition
Sampling before and during treatment Sampling after treatment
After settling for 24 hrs• Sludge depth was determined (4.5 to 5 ft)• Samples – sludge and supernatant taken for
analysis
Sampling after treatment
Scum thickness (layer at top) – approx. 1.5 in.
After treatment (24 h settling)Before Treatment (lbs/1,000 gal.)
Ammonia N: 3.84Org N: 3.76P2O5 : 2.98K2O: 10.27
Ortho-P: 0.30
Sludge Supernatant
(lbs/1,000 gal.)Ammonia N: 3.92
Org N: 8.76P2O5 : 7.72K2O: 9.85
Ortho-P: 0.19
(lbs/1,000 gal.)Ammonia N: 3.50
Org N: 1.42P2O5 : 0.73K2O: 9.82
Ortho-P: 0.13
Land Application - Trucks
4,000 gal tank
6,000 gal tank
Land Application - Loading
4,000 gal tank(30 min to fill, transport
& land apply)
6,000 gal tank(35 min to fill, transport
& land apply)
Land Application – Transport Land Application
Application rate3 000 l3,000 gal per acre
Pasture: 30 acresAlfalfa: 27 acres
Land Application – Manure on land Empty Tank: 6 inches of residual sludge
Struvite Recovery from Dairy Manure
• Magnesium Ammonium Phosphate
• Currently under study• Washington State, Idaho,
Virginia Tech• Challenges: Calcium
interference; Suspended material; appropriate treatment
Enhanced Biological P Removal from Dairy Manure
How it works
• A group of bacteria (phosphorus accumulating organisms - PAOs) under the right environmental conditions and feeding will take more phosphorus than they need for growth – Luxury uptake
• Harvest the bacteria after taking up excess P
Enhanced Biological P Removal from Dairy Manure
• Not aware of full scale systems on dairy farms
• Virginia Tech: Testing pilot scale system for liquidVirginia Tech: Testing pilot scale system for liquid dairy manure in a sequencing batch reactor with prefermentation to enhance volatile acid production in manure fed to the reactor
EBPR from Dairy Manure
Waste tank
SBR 2 Fermenter 2 SBR 1 Fermenter 1 Feed tank
EBPR from Dairy Manure – emerging results
Ortho-P concentration in Feed, Effluent, and mixed liquor
EBPR from Dairy Manure – emerging results
Total P concentration in Feed, Effluent, and mixed liquor
Summary
• You can make designer manure using chemicals and polymers
o In a continuous flow systemo Batch Systems
• Amount of chemicals used will depend onAmount of chemicals used will depend on the extent of nutrient reduction required
• Biological methods are still under development but can be very effective just like the chemical methods
Thank You
Questions?
Source: Moffatt B., AgStar Conference 2007
Contact:Jactone Arogo OgejoBiological Systems EngineeringVirginia Tech(540) 231 [email protected]