Title: Environmental Systems and Facilities Planning
1Environmental Systemsand Facilities Planning
Doug Overhults Larry Turner University of
Kentucky Biosystems Agricultural Engineering
2Topic Outline
- Psychrometrics Review
- Energy Balances/Loads
- Latent heat
- Sensible heat
- Solar loads
- Insulation Requirements
3Topic Outline
- Ventilation Systems
- Rate requirements
- System requirements
- Moisture Control Standards
- Air Quality Standards
- Humans
- Animals
- Plants and Produce
4Psychrometrics
- Variables
- Using the Psychrometric Chart
- Psychrometric Processes
5Psychrometric Chart
Humidity Scale or axis
State Point
Dry Bulb Temperature Scale (axis)
6Psychrometric Chart(temperatures relative
humidity)
Example 70 oF dry bulb 55 oF dew-point 61 oF
wet-bulb 60 rh
relative humidity
Humidity Scale
dew-point
wet bulb
dry bulb
Dry Bulb Temperature Scale
7Psychrometric Processes
- Heating, cooling, humidifying, dehumidifying
air-water vapor mixtures - Five basic processes to know
- Heat or Cool (horizontal line)
- Humidify or De-humidify (vertical line)
- Evaporative cooling (constant wet-bulb line)
8Heating dry bulb increase
Humidity Scale
Horizontal line means no change in dew-point or
humidity ratio
ending state point
starting state point
Dry Bulb Temperature Scale
9Humidification dew-point increase
Humidity Scale
end state
Vertical line means no change in dry bulb
temperature RH goes up!
start state
Dry Bulb Temperature Scale
10Evaporation wet bulb increase
Humidity Scale
Increase in vertical scale humidified Decrease
in horizontal line cooled
end state
Constant wet bulb line
start state
Dry Bulb Temperature Scale
Adiabatic process no heat gained or lost
(evaporative cooling)
11Review
- Name three temperature variables
- Name three measures of humidity
- Name the two main axes of the psychrometric chart
- Name the line between fog and moist air
- Heating or Cooling follow constant line of ?
- Humidify/Dehumidify follow constant line of ?
12Energy and Mass Balances
- Heat Gain and Loss
- Latent and Sensible Heat Production
- Energy Loads
- Solar Load
- Moisture Balance
13Heat Gain and Loss
- Occupants
- Lighting
- Equipment
- Ventilation
- Building Envelope
- Roof, walls, floor, windows
- Infiltration (consider under ventilation)
14Heat Loads
- Occupant (animals, people)
- Sensible load (e.g. Btuh/person)
- Latent load ()
- Lighting, W/m2
- Appliance W/m2
- Ventilation air (cfm/person or animal)
- Equipment (e.g. Btuh for given items)
15Ventilation
- Temperature control
- Moisture control
- Contaminants (CO2) control
- Energy use
- Pressure, velocity calculations
16Latent and Sensible Heat Production
- Example from ASAE Standard EP270.5
Table 1. Moisture Production, Sensible Heat
Loss, and Total Heat Loss Cattle
Bldg. T MP SHL THL 500 kg 21C
1.3 gH2O/kg-h 1.1 W/kg 2.0 W/kg
17Sensible Energy Balance
- Leads to Ventilation for Temperature Control
qs qso qm qh SUA(ti-to) FP(ti-to)
cp?V (ti-to)
Heat inputs envelope floor
ventilation
18Sensible Energy Balance
- Leads to Ventilation for Temperature Control.
Rearranging
V qs - ( S UA FP)(ti-to) / 0.24 ? (ti-to)60
V cfm (equation for English units)
19Mass Balance
Moisture, CO2, and other materials use balance
equations.
mp Material produced
mvi Material input rate
mvo material output rate
20Moisture Balance
Example balance for moisture control removal rate.
/
mair Ventilation rate
Mwater Moisture to be removed
(Wi-Wo) Humidity ratio difference
Q (V / 60) x Wr / (Wi-Wo)
Q - cfm V ft3/lb da
21Find the minimum winter ventilation rate to
maintain 70 relative humidity inside a swine
nursery that has a capacity of 500 pigs weighing
20 pounds. Inside temperature is 75 degrees.
- Find moisture production data
- ASABE Standards (EP270.5)
- W 0.044 lb/hr/pig
- Get psychrometric data from chart
- W0 0.0005
- Wi 0.0130
- V 13.75
- Plug into equation solve
- Q 403 cfm
22Moisture Balance
Find the minimum winter ventilation rate to
maintain 60 relative humidity inside a swine
nursery that has a capacity of 800 pigs weighing
10 pounds. Inside temperature is 85 degrees.
23Find the minimum winter ventilation rate to
maintain 60 relative humidity inside a swine
nursery that has a capacity of 800 pigs weighing
10 pounds. Inside temperature is 85 degrees.
- Find moisture production data
- ASABE Standards (EP270.5)
- W 0.017 lb/hr/pig
- Get psychrometric data from chart
- W0 0.0005
- Wi 0.0154
- V 14.1
- Plug into equation solve
- Q (14.1/60) x (.017 x 800) / (.0154 - .0005)
- Q 214 cfm
24Energy Balance
What is the ventilation rate for a swine
finishing barn that will limit the design
temperature rise inside the house to 4 degrees
(F) above the ambient temperature? The barn
capacity is 1000 pigs at 220 pounds and the
inside temperature is approximately 85 F. The
overall heat transfer coefficient for the barn is
1200 Btu/hr F.
25What is the ventilation rate for a swine
finishing barn that will limit the design
temperature rise inside the house to 4 degrees
(F) above the ambient temperature? The barn
capacity is 1000 pigs at 220 pounds and the
inside temperature is approximately 85 F. The
overall heat transfer coefficient is 1200 Btu/hr
F.
- Find heat production data
- ASABE Standards (EP270.5)
- q 0.49 W/kg (sensible heat)
- Convert units calculate total heat load
- q 0.49 W/kg x 100 kg/pig x 1000 pigs
- 49,000 W x 3.412 Btu/hr W
- 167,188 Btu/hr
- Density of Air 0.075 lb/ft3
- Specific heat of air 0.24 Btu/lb F
- ti to 4 F
- Plug into equation solve
- V 167,188 - (1200 x 4) / (0.24 x 0.075) x 4
x 60 - V 37,590 cfm
26Fan Operating Cost
Electrical Power Cost
V Ventilation volumetric flow rate
W Power input, Watts
cfm / Watt Fan Test Efficiency
27Calculate Operating Costs
- Design Ventilation Rate 169,700 cfm
- Fan Choices
- Brand A 21,300 cfm _at_ 19.8 cfm/watt
- Brand B 22, 100 cfm _at_ 16.2 cfm/watt
- Fans operate 5200 hours per year
- Electricity cost - 0.08 per kWh
- Calculate annual operating cost difference
28Calculate Operating Costs
- 8 fans required for brand A or B
- Use EP 566, Section 6.2
- Annual cost is for all 8 fans
29Reference
MWPS - 32
Contains ASABE heat moisture production data
example problems
Midwest Plan Service Iowa State University Ames,
IA
30References Env. Systems
- Albright, L.D. 1990. Environment Control for
Animals and Plants. ASAE - Hellickson, M.A. and J.N. Walker. 1983.
Ventilation of Agricultural Structures. ASAE - ASHRAE Handbook of Fundamentals. 2001.
- ASHRAE 4-Volume Handbook CD 1998-2001
31Reference
MWPS - 1
STRUCTURES and ENVIRONMENT HANDBOOK
Contains ASABE heat moisture production data
example problems
Midwest Plan Service Iowa State University Ames,
IA
32Useful References Env Sys
- MidWest Plan Service. 1990. MWPS-32, Mechanical
Ventilation Systems for Livestock Housing. - Greenhouse Engineering ISBN 0-935817-57-3
http//www.nraes.org/publications/greenhouse.html
33References ASAE Standards
- EP270.5 Ventilation systems for poultry and
livestock - (X 567 Mechanical Ventilation Systems for
Livestock) - EP282.2 Emergency ventilation and care of
animals - EP406.4 Heating, ventilating cooling
greenhouses - EP475.1 Storages for bulk, fall-crop, irish
potatoes - EP566 Selection of energy efficient ventilation
fans
34Facilities Planning
- Functional and space requirements
- Electrical wiring/lighting devices
- Construction materials (concrete, steel, wood,
etc.) - Hazardous materials storage
35Space Function Requirements
- Human, animal, machinery and vehicle traffic
- Building footprints, separation distances
- Planning zones, circles
- Functional planning (manure, young stock, mature
animals, machinery) - Hazardous storage, pesticides
- Wind patterns and air flow, solar loads, traffic
patterns - Utility systems and access
- Codes, zoning, and setback distances
36Electrical Wiring / Lighting
- Electrical loads
- Service Branch Circuits
- Motor sizes, loads
- Wire sizing
- Lighting selection, requirements
- Codes
37Construction Materials, Hazardous Material Storage
- Concrete mixtures, surface treatments, lumber
grades, steel selection - Pesticide containment
- Fertilizer storage
- Safety considerations, OSHA, codes
38Manure Management Facilities
- Animal Manure Production
- Nutrient Production
- Design Storage Volumes
- Lagoon Minimum Design Volume
- References
- ASAE EP 384.2, 393.3, 403.3, 470
- NRCS Ag. Waste Field Handbook
39Size a Manure Storage
- 1 year storage
- Above ground 90 dia. tank uncovered
- 2500 hd capacity grow/finish pigs
- Building turns over 2.7 times/yr
- Manure production 20 ft3/finished animal
- Net annual rainfall 14 inches
- 25 yr. 24 hr storm 5.8 inches
40Size a Manure Storage
- Use EP 393, sections 5.1 5.3
- Total volume has 5 components
- Manure, Net rainfall, 25 yr-24 hr storm
- Incomplete removal, Freeboard for agitation
41Size a Manure Storage
- Manure Depth 21.22 ft.
- Net rain 1.17 ft
- 25 yr-24 hr storm 0.48 ft
- Incomplete removal 0.67 ft
- Freeboard 1 ft
- Total Tank Depth 24.54 ft.
42References - Facilties
- Agricultural Wiring Handbook, 14th edition,
National Food and Energy Council - Farm Buildings Wiring Handbook, MWPS-28 (now
updated to 2005 code) - Equipotential Plane in Livestock Containment
Areas ASAE, EP473.2 - Designing Facilities for Pesticide and Fertilizer
Containment, MWPS-37 - On-Farm Agrichemical Handling Facilities,
NRAES-78 - Farm and Home Concrete Handbook, MWPS-35
- Farmstead Planning Handbook, MWPS-2
(availability?)
43Thank YouandGood Luck on Your PE Exam ! !