Transcript Rural Development - Great Lakes Water Conservation Conference

Life Cycle Assessment for
Cheese Plants
FX Milani
UW-Madison
Wisconsin Dairy Products Association
September 28, 2010
FIL/IDF, UN-FAO dairy report
World dairy
contributes 4% of
all manmade green
house gases
Nat’l Project Cheese & Whey LCA
Wisconsin cheese and whey
Who: Rural development is VERY interested
in the contribution of cheese/dairy
manufacturing
 What: Concern about sustainability issues,
want to find “hot spots” and new potential
returns
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Wisconsin cheese and whey
Where: Wisconsin based manufacturing
 When: This year and next spring, beyond?
 Why: Ultimately, dairy manufacturing is
vital
 How: Survey work to get baseline
concerns and data, model potential ideas,
investigate best ideas
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The projects: 3 this year
◦ Sustain Metrics:
 UW Food Science, CDR,UW Biological Systems Engineering
 F. Milani, D. Reinemann, D. Sommer, students
 Modeling, Survey audits, Outreach program, Reports
◦ Whey Disposal:
 UW Food Science, CDR, Industrial Partners
 F. Milani, M. Molitor, D. Sommer, Contractors
 Survey audits, Whey/permeate data, Waste water data,
Reports/potential
◦ Sustainability Outreach:
 UW Food Science, Biological Systems Engineering
 F. Milani, A. Newenhouse
 Short course, Involvement with 2011 WCMA LaCrosse,
Outreach materials, Bus trips
Specific information to collect
Energy use: gas, electric, wood, LP, etc
 Transportation use
 Refrigerant use
 Raw material, chemical use
 Packaging use
 Water use, wastewater generated
 Pounds and types of cheese produced

Milk composition
Water
Fat (emulsion)
Protein
(colloidal suspension) Casein
(true solution)
Lactoglobulin
“
Lactalbumin
“
Others
Lactose
Minerals (ash)
87.8%
3.7
3.1
(2.5)
(0.3)
(0.07)
(0.22)
4.7
0.7
Cheese Yield 10%, ~50% solids loss
to whey
Percent milk constituents
Milk is high in phosphorous
Food item
mg of P / Liter
Milk
930
Cream
710
Eggs
USDA Handbook 8
1800
Cheese P loss to whey (50-90%)
Cheese Type
mg of P / Liter
Cheddar
546
Colby
526
Jack
575
Mozzarella
519
Swiss
447
Brick
465
(Wendorff & Matzke, 1993)
The 4 F’s of whey
High
Value
$
FOOD
Feed
$
Low
Value
Fuel
Fertilizer
Options for whey
Sell to aggregate processor
 Land spread
 Concentrate and sell (wet or dry)
 UF concentrate, sell wet protein
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◦ Permeate: sell wet or land spread
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UF concentrate, sell dry protein
◦ Permeate: sell dry lactose, dry/landspd wet DLP
◦ (note: lactose market is very volatile)

UF concentrate, sell wet protein
◦ Permeate: biogas, dump minerals
Average Wisconsin cheese plant
44.7 M pound cheddar cheese annually
 28.8 M pounds sweet whey equivalent
 447 M pounds milk (1.2 M pounds per day)
 116 k gal per day water use, high vary
 230 k gal per day wastewater flow, med vary
 14,355 kWhr per day electric
 6568 therms per day natural gas
 459,801 pounds of caustic annual use

Citations listed at end of presentation
Wastewater and Carbon Footprint
Short Courses, November 9-11
http://www.foodsci.wisc.edu
http://www.cdr.wisc.edu
Citations for average cheese plant
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Cheese production:
http:www.nass.usda.gov/Statistics_by_State/Wisconsin/
Publications/Annual_Statistical_Bulletin/annbull_2008.pd
f
Whey conversion: USDA Handbook 8
Milk Input: Van Slyke equation for cheddar cheese
Water use: Fietz et al. Int. J. LCA 12(2) 109-17, 2007
Wastewater output: Danalewich, et al. Wat. Res. 32(12)
3555-68, 1998
Electric and natural gas use: C. Ling et al. USDA report,
2004
Sodium Hydroxide use: Fernadez, et al. J. Food Eng 97,
319-28, 2010
How much energy is in permeate?
Yield of pure carbohydrate is 0.38 cubic
meter methane per kg lactose
 1 kg lactose is 13,300 BTU, or 0.133 therm
 1 therm is $0.475
 1 kg lactose is $0.063, or $0.029 per pound
 Current market lactose is $0.29-0.35, less
drying cost at about $0.19, plus operational
3-12 cents, profitable now, but…
 Wet permeate is 4.5% lactose

Carbon credits with lactose
1 kg lactose produces 0.38 cubic meters
methane, and 0.74 kg CO2
 2685 kg of lactose produces mton CO2
 Assume EU trading at $15 per mton, get
additional $0.0055 per kg lactose ($0.0025
per pound)
 $50,287 per year new revenue
 Consumer milk is burdened with1.2 CO2
per kg milk. Milk contains 45 g lactose,
potential 0.033 kg CO2 / kg milk carbon
credit from lactose
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Whey processing steps
Drained Whey
Fines Saver
Cheese Fines
Separator
Whey Cream
Clarified whey
Pasteurization
RO
Evaporator
Condensed
Whey
To Processor
Whey Processing steps
Condensed Whey
Crystallizer
Spray Dryer
Dry Sweet Whey
Whey Protein Concentrate
Permeate processing
Important nutrients in whey
Nutrient
N
P
K
Ca
Mg
Na
Whole whey
12.2
4.0
14.6
2.9
0.55
4.2
Whey permeate
2.0
3.8
8.2
2.7
0.59
3.4
Benefits to landspreading
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Nutrient recycling
Residual fertility
Soil physical properties
Cost effectiveness
Pollution reduction
Land spreading, Chloride, WI
Ave. Cl (mg/L) Gal/A/yr.
1183
16,000
Salty whey
56,900
500
Used brines
187,000
89
Whey/permeate
Issues with landspreading
Nitrogen content
 Salt concentration
 Soil oxygen levels
 Odors
 Soil limitations
 Seasonal limitations (injection)
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