Thermal hyrolysis of biosolids & bnr digester lystek
Report in msa
1. Pig Housing Systems Designed to
Manage or Adapt to Climate Change
Presented at:
Minnkota Meeting
March 16, 2012
Larry D Jacobson, Professor & Extension Engineer
University of Minnesota
2. Introduction
• Generally accepted that climates in the
major pig production areas of the U.S.
(Midwest and Southeast) are becoming
warmer with higher moisture or dewpoint
temperatures.
• A warmer and wetter climate will only
increase the need to lower barn
temperatures in production facilities, which
is very limited in present building designs.
3. “Green Pig Barn” Project Objectives
• Develop a swine finishing building for
Midwestern U.S. based on building design
criteria that reduces the housing system’s
environmental footprint (lowers energy & water
usage and airborne emissions by 50%) while
maximizing utilization of manure/waste
products
• Provide guidance to retrofit existing finishing
barns to reduce energy use and emissions.
4. Key Design Criteria
• Integrated Design
– No add on technologies that do not benefit the
production system
• Replace current 2400 head “tunnel ventilated”
finishing barn in upper midwest (traditional deep
pit with curtain or power ventilation)
• Must account for total housing system
emissions (e.g. manure storage emissions
must be included)
5. Tunnel Ventilated Finishing Barn
• Double wide- 2 – 1200 rooms
or 2400 head total – approx.
max ventilation 120 cfm/pig
• Winter ventilation – mostly
pit fans but some end wall
fans using ceiling inlets
• Summer ventilation – both
pit and all end wall fans with
primary inlets from opposite
end wall curtain
6. Other Important Factors
• Design should optimize the barn
environment AND pig performance to offset
added capital investment or labor costs
Thermoneutral Zone
8. Other Factors to Consider
• Design should improve worker environment
and reduce safety hazards (foaming and H2S
hazards with agitation and pumping)
9. Other Important Factors
• Emissions, energy, and economics
calculated on per pound of pork produced
rather than on per area or animal number
– Emissions may be more per barn but if more
product (pork) is produced . . . we are getting
less emissions per unit of production
10. Energy Use in Pig Production
• Direct (Fossil Fuel) Energy
– Primarily L.P. Gas and electricity
– About 2 to 5% of pig production cost (UMN
Farm Financial Management)
• Indirect (Feed) Energy
– Feed efficiency, rate of gain
– Estimated to be 60 to 70 %
of pig production costs
11. Key Emission Control Factors
• Move manure out of the barn – avoid long-
term pit storage of manure under barn
– Reduces risks of pig losses during pumping
– Improves Indoor Air Quality
– Reduce ventilation requirements
– Reduce barn emissions
• Reduce ventilation
• Reduce temperature
13. Final Design Summary
• 2400 head, double wide, mechanically
ventilated barn
• Ceiling inlets for 100% of ventilation air
• Four barn versions (A,B,C,&D)
– Flooring (partial slats - A & B & full slats –C & D)
– Different Heating and cooling systems
14. Barn Design Options Matrix
Partially Slatted Version A: Geothermal
and heat pump for
heating and cooling (PEX
tubing) floor (40 T
heating and cooling) plus
direct fire for room heat.
(80 cfm/pig max)
Version B:
Geothermal only
heating and cooling of
floor and room (135 T
heating and cooling)
(40 cfm/pig max)
Fully Slatted Version C: Evaporative
Cooling only (twice
normal cooling capacity)
(100 cfm/pig)
Version D:
Geothermal heating
and cooling of room
air (135 T heating and
cooling) (40 cfm/pig
max)
NOTE: All barns include outdoor covered manure storage
17. Green grow-finish barn’s
inlets & air tempering
• Tempering halls at ends of barns for heat
exchangers or cool cells
• All air brought in through ceiling inlets
18. Energy and Emissions Estimates
(in comparison with existing tunnel ventilated barns)
Version of
Barn
Electric use LP use Emissions
Version A Slightly more Slightly less less
Version B Slightly less Slightly less Much less
Version C Equal Equal Slightly less
Version D Slightly less Slightly less less
19. Economic Evaluation1
Variables Considered
• Investment
• Feed efficiency
• Death loss
• Pig health cost
• Electric use
• LP use
• Market Price
• Other costs
Constants
• Start and end weight
• Weaned pig cost
• Days to end group
• Between Group Time
• Feed cost
• Facility life
1Done by Bill Lazarus and Bob Koehler
20. Key Input parameters that were
varied for the Economic Analysis
Item Baseline Version A Version B Version C Version D
Const. costs /
pig space1
$260 $400 $510 $350 $525
ADG2
lb/day
1.55 1.62 1.66 1.60 1.66
FE2
lb feed/lb gain
2.75 2.55 2.45 2.60 2.45
1Bids from SW MN field engineers to build barn & manure storage
2,3Based on 2009 Finbin records of 36 farms with adjustments for cooled facilities
21. Economic Summary - Results
Item Baseline Version A Version B Version C Version D
Profit/pig $3.73 $6.65 $4.95 $8.18 $5.30
NPV1/pig
space
$5.95 $2.43 $9.03 $3.12
Years to
Payback
additional to
baseline
1Net Present Value
9.1 12.8 6.0 12.5
22. Economic Analysis Discussion
• Many assumptions & crude sensitivity analysis
– Slight changes in animal performance (ADG
and FE) will have dramatic impact on results
– Feed costs will also have a large impact
• Not captured by Economic Analysis
– Worker health, regulations and permitting
benefits, death loss (pigs) with agitation and
pumping
24. Heat
Percent of air exhausted
to remove CO2
Makeup air added to replenish O2
Pigs
Add Heat, Moisture, and Gasses
to Air
Optional
Antimicrobial
Filter in makeup
air
Bacteria, Viruses, and
Dust Removal
Water to Air Heat
Exchanger
Heat Added
Combination of Biotrickling and
Biofilter
H2S, NH3, and other Gasses Removal
Water to Air Heat Exchanger
Heat Removed for
Dehumidification
Moisture removed from
air
Water
Heat StorageHeat A
B
C
D
E
F
G
24
25. • Develop a new barn design concept for
swine production that would reduce
emissions and improve feed efficiency.
25
Air
Cleaner
&
Conditioner
28. 28
Biotrickling Filter
Biofilter
Air Inlet
CO2 Exhaust Fan
Heat/Water
Storage Tank
Air Return to Swine Room
Heat Exchanger
to cool air and
Condense Moisture
Heat Exchanger
to Reheat Air
Ambient Air Inlet
Heat Pump
