MANURE HANDLING AND STORAGE TO MINIMIZE N LOADING OF THE ENVIRONMENT

1
MANURE HANDLING AND STORAGE TO MINIMIZE N LOADING
OF THE ENVIRONMENT

• Reason to store manure
• Preserve and contain manure nutrients until it
  can be spread onto the land at a time compatible
  with climate and cropping system
• Goals
• Maintain excreted N in non-volatile organic forms
• Undigested protein
• Microbial N
• Urea
• Minimize volatilization of NH3
• If N is volatilized, it should be in the form of
  N2
• Prevent losses of N into surface and ground water
  sources
• Provide adequate storage until it can be safely
  spread

2
N TRANSFORMATIONS IN LIVESTOCK PRODUCTION AND
MANURE STORAGE FACILITIES

• Manure N
• Anerobic microbial
  C skeletons H2S
• degradation (slow)
  
  VOCs
• Fecal N
• (20-40 of N)
• 
  
  Microbial N
• 
  
  
• 
  NH4 Slow
• Urine N
  aerobic
  Anerobic
• (60-80 of N) Microbial
  NH3 NO2
  N2
• O
  urease (rapid) pH (volatile)
• H2N C NH2 H H2O
  2NH4
• 
  2HCO3-

• In poultry
• Urinary N is secreted as uric acid with the feces

3

• NH3 volatilization increased by
• Increasing rumen pH
• Increased by increased HCO3 and NH3
• Increasing moisture
• Increasing temperature
• From outside of confinement buildings
• Greater ventilation
• Concentrations of NH3 greater inside confinement
  buildings in cold weather
• From outside lots
• Greater surface area

4
METHODS TO LIMIT AMMONIA VOLATILIZATION FROM
MANURE

• Dietary approaches
• Reduce N excretion
• Feed acidic Ca and P sources to decrease manure
  pH
• Examples
• Calcium chloride
• Phosphoric acid
• Limitations
• Unpalatable
• May cause ulcers in mouth
• Feed Yucca extract
• May inhibit microbial urease

5

• Technological approaches
• Frequent removal of manure from facilities
• Ne feedlot
• One-time cleaning, 68 N loss by volatilization
• Monthly cleaning, 55.5 N loss by volatilization
• Increase carbon in manure
• Increases CN ratio to increase microbial growth
• Approaches
• Feed more fiber
• Use more bedding
• Separate liquid and solids
• Separates urea in urine from urease in feces
• Methods
• Gravity (Inclined floors, sedimentation pits)
• Mechanical (Screens, centrifuges, presses)
• Separated solids
• Land applied
• Composted
• Liquids

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COMMON MANURE STORAGE

• Solid
• Systems
• Poultry
• Litter
• Swine and Dairy
• Separated solids
• Bedded manure
• Beef
• Scraped
• Facilities
• Concrete pad with sides
• Settling basins
• Advantages
• Low volume
• Low odor
• Moderate nutrient retention
• Disadvantages
• More labor
• Must prevent precipitation run-off

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BEEF FEEDLOT WITH SETTLING BASIN
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• Composting
• Treatment to stabilize N
• Requirements
• Appropriate CN ratio
• 
  CN
• Optimum
  gt301
• Manures
• Dairy cow
  101
• Beef cow
  101
• Beef feedlot
  131
• Swine
  7-81
• Poultry
  7-91
• Horse
  191
• Temperature
• 140o F
• Requires frequent turning
• Moisture level
• 40-60
• Adequate porosity

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• Slurry
• For livestock and poultry confinements
• Facilities
• Pit under slatted floor
• Needs access ports for pumping and agitation at
  40 foot intervals
• Ventilation is necessary
• Manure is either applied directly or after
  storage
• Fabricated storage tank
• Manure is either scraped or pumped into structure
• Easily covered
• Earthen basin
• Provides a large volume at low cost
• Soil materials must seal basin
• Vegetation must be maintained on berms
• Advantages
• Less volume than liquid storage
• Possible to cover to reduce volatilization
• High nutrient retention, if covered
• Disadvantages

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SLURRY SYSTEMS
11

• Covers to limit NH3 and odor release

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• Liquid systems
• Anerobic lagoons
• Most common liquid system
• Usually treats liquid fraction separated from
  solids
• Requires warm temperatures for microbial activity
• Advantages
• Large storage volume
• Can use conventional pumping equipment
• Disadvantages
• Very high NH3 volatilization
• Requires appropriate soil materials to seal
  lagoon
• Requires solids separation
• Manure additions must be slow and uniform
• High odor in spring when microbial activity
  increases under Midwest conditions
• Requires periodic sludge removal

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• Alternate treatments to limit NH3 loss from
  liquid systems
• Aeration
• Converts NH3 to NO3
• Requirements
• Second lagoon with aerator
• Surface pump
• Compressed air
• Aerobic biofilters
• One lagoon with 2 compartments
• Aerobic top and Anerobic bottom
• Disadvantages
• Expense
• Limited effectiveness
• Production of NOx gases
• Methane production
• Enclosed anerobic fermentation
• Can supply energy for farm or for sale
• Requires additional structure for storage of
  effluent
• Good N retention if additional storage is covered

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• Constructed wetlands
• For processing liquid fraction after solids
  separation
• N trapped in plants growing in or on wetland
• Types
• Surface
• Most common
• Subsurface
• Water treatment in a gravel bed
• Works better in winter than surface wetland
• May plug
• Reciprocating
• Recurrently fill and empty
• Causes aerobic and anerobic zones

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N LOSSES FROM DIFFERENT MANURE HANDLING AND
STORAGE SYSTEMS

• 
  N loss, N retention,
• Daily scrape and haul from barn
  20-35 65-80
• Open lot
  40-70 30-60
• Pile (Cattle/Swine)
  10-40 60-90
• Pile (Poultry)
  5-15 85-95
• Compost 20- 50
  50-80
• Deep pit (Poultry)
  25-50 50-75
• Litter
  25-50 50-75
• Pit under floor (Swine)
  15-30 70-85
• Tank above ground top loaded
  20-35 65-80
• Tank above ground bottom loaded
  5-10 90-95
• Tank above ground with cover
  2-30 70-98
• Holding basin
  20-40 60-80
• Anerobic lagoon w/ no cover
  70-80 15-30
• Constructed wetlands
  15 85

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FACTORS AFFECTING SIZE OF MANURE STORAGE

• Volume of manure and wastewater produced
• Include wash water, run-off from open lots and
  feed storage, and water for flushing
• Limitations for spreading
• Amounts of land available for spreading
• Crop nutrient requirements
• Length of storage period
• Climatic limitations
• Length of application windows
• Needs
• A minimum of 6 months storage
• Equipment capabilities
• Discharge regulations
• All beef and dairy CAFOs
• No discharge except for a 25-year, 24-hour storm
• All new or renewed swine, poultry, and veal CAFOs
• No discharge except for a 100-year, 24-hour storm

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MANURE APPLICATION TO MINIMIZE N LOADING

• Considerations
• Manure N concentration
• Needs laboratory analysis to adjust for factors
  like diet, volatilization, water dilution, and
  bedding
• If developing a CNMP, need to consider total N
  production
• 
  Manure N (lb N/lb animal
  wt/yr)
• Swine
• Nursery
  .22
• Growing
  .15
• Finishing
  .15
• Sows and litter
  .17
• Sow gestation
  .07
• Gilts
  .088
• Boars
  .055
• Beef
• 450-750 lb
  .11
• High energy finish
  .11
• Cows
  .12
• Dairy
• 50 lb milk/d
  .18

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• Availability of N to plants (PAN)
• PAN Organic N x mineralization rate NH4-N x
  volatilization factor
• NO3-N
• Mineralization rate of organic N
• Generally slow
• Increases with
• Lower soil moisture
• Increased soil temperature
• Increased soil pH
• Nutrients for soil microbes
• Average rates
• Soil moisture OM-N
  available
• lt 18 35
• gt 18 25

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• Volatilization of NH3
• Very rapid with surface application
• Rate dependent on
• Application method
• Lower with injection or incorporation
• Temperature
• Greater from surface applied at higher
  temperature
• Plant uptake
• Losses lower when plants actively growing
• Average factors
• Application method
  NH4-N available
• Injected or side-dressed during growing
  100
• season
• Injected or incorporated in spring
  65
• (Reduce by 12 for each day delay in
  incorporation)
• All other conditions
  0

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• Plant Available Nitrogen (PAN)
• After storage loss
• Storage type Proportion of manure N
  available after storage
• Feedlot
  .60
• Manure pack under roof .70
• Bedded swine
  .50
• Liquid/slurry, covered
  .90
• Liquid/slurry, uncovered
  .75
• Storage pit under slats
  .85
• Poultry manure on shavings
  .70
• Compost
  .70
• Anerobic lagoon
  .20

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• After application
• 
  ___________Application method______________
• 
  Soil incorporation Broadcast
  Irrigation
• 
  Proportion of manure N available after
  application
• Scraped manure
• Livestock
  .6 .5
  -
• Poultry litter
  .6
  .5 -
• Liquid slurry
• Dairy or Beef
  .7 .5
  .4
• Swine
  .7
  .4 .3
• Layers
  .7
  .5 .4
• Anerobic lagoon
• Dairy or Beef
  .8 .5
  .5
• Swine
  .9
  .5 .5
• Layer
  .9
  .5 .5
• Total PAN Total N x ( PAN after storage x PAN
  after application)
• Examples
• PAN of Feedlot manure applied with incorporation

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• Other N sources
• N-fixation by legume plants
• Supplies enough N to meet legume plant needs for
  growing year
• N-fixed by legume plants for following year
• 
  lb plant available N/acre/year
• Soybeans
  30-45
• Alfalfa
  50-125
• N fertilizer
• Rates should be calculated as the difference
  between plant N needs and PAN from manure and
  legumes
• Crop N needs
• Nutrients should be applied to achieve Realistic
  Yield Expectations of the crop
• The Agronomic rate
• Realistic yield expectations
• Factors
• Soil fertility
• Soil management
• Climate
• Plant populations
• Pest control

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• Plant N requirement for yield
• N
  removal in Efficiency of
• 
  harvested crop, N use, N
  required
• Crop wet
  basis ____ for crop
• Corn
• Grain .81
  lb/bu 83 .97
  lb/bu
• Stover (Baled) 17.80 lb/ton
  100 17.80 lb/ton
• Soybeans
• Grain 3.54
  lb/bu 166 2.13
  lb/bu
• Stover (Baled) 13.60 lb/ton
  100 13.60 lb/ton
• Alfalfa (Baled) 46.10 lb/ton
  200 23.05 lb/ton
• Bromegrass (Baled) 39.20 lb/ton
  100 39.20 lb/ton
• Reed canarygrass (Baled) 28.00 lb/ton
  100 28.00 lb/ton
• Switchgrass (Baled) 21.80 lb/ton
  100 21.80 lb/ton
• Alfalfa haylage 25.90 lb/ton
  200 12.95 lb/ton
• Corn silage 9.00
  lb/ton 100 9.00
  lb/ton

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• Calculating manure application rate based on N
• Plant available N Realistic yield expectation x
  Crop N reqt.
• needs
  
• Manure application Plant available N reqt / PAN
  conc in manure
• rate
• Example
• Say Corn yield 180 bu/acre
• PAN needed, lb/acre 180 bu/acre x .97 lb
  N/bu 174.6 lb PAN/acre
• Say Swine lagoon manure containing 50 lb
  PAN/1000 gal which will be injected
• Manure applied, gal/ac 174.6 lb PAN/ac / 50
  lb N/1000 gal
• 
  3,492 gal/ac

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USING CROPS TO MINE MANURE N

• Some CAFOs look at harvested crop as method to
  remove manure N from operation
• Potential amounts of N removed
• Crop RYE
  N removed/unit lb total N removed/acre
• Corn grain 180 bu
  .81 lb/bu 146
• Corn stover (Baled) 4 ton 17.80
  lb/ton 71
• Soybeans 55 bu
  3.54 lb/bu 195
• Alfalfa (Baled) 5 ton
  46.10 lb/ton 230
• Bromegrass (Baled) 4 ton 39.20
  lb/ton 156
• Reed canarygrass 5 ton 28.00
  lb/ton 140
• (Baled)
• Corn silage 20 ton
  9.00 lb/ton 180
• Considerations
• To mine N, crop must either be sold or used in
  the diet to reduce purchase of protein
  supplements on farm
• Grazing is effective at recycling N
• Therefore, grazing is ineffective for mining
  nutrients
• If N is applied at the agronomic rate, Phosphorus
  will accumulate
• N rate is 2 to 3 times greater than the P rate

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CONSIDERATIONS IN MANURE APPLICATION

• Application rate
• Method
• Surface application
  Injection or incorporation
• Greater N volatilization
  Less N volatilization
• Greater potential for N loss in run-off
  Less run-off potential
• Nutrients further from crop roots
  Nutrients near roots
• Site
• In Iowa, manure application can not occur within
  200 feet of a surface water source if no
  vegetative buffer
• In Iowa, manure application may occur up to 50 ft
  if vegetative buffer and manure is incorporated
• Timing
• Manure should be applied shortly before nutrients
  will be used for growth
• 30 days