Food Waste Diversion at Correctional Facilities Composting Technologies and Costs

1
Food Waste Diversion at Correctional
FacilitiesComposting Technologies and Costs

• Craig Coker
• Organics Recycling Coordinator
• DENR/ Div. Of Pollution Prevention
  Environmental Assistance

2
Overview

• Technology in Composting
• Materials Handling
• Biological Process Optimization
• Odor Control
• Capital Cost
• Increases with technology
• Operational Costs
• Decrease with technology
• Footprint (Area Required)
• Decreases with technology (usually)

3
Technology Classification

• Low - Tech
• Windrow
• Mid - Tech
• Aerated Static Pile
• Aerated Compost Bins
• High - Tech (In-Vessel)
• Rotary Drum Composters
• Box/Tunnel Composting Systems
• Mechanical Compost Bins

4
Windrow Composting

• Long, narrow piles agitated/turned regularly
• Aeration by natural/passive air movement
• Better suited to larger volumes
• Composting Time 3 - 6 Months

5
Windrow Composting, cont.

• Equipment Needed
• Grinder/Shredder
• Tractor/FEL
• Windrow Turner
• tractor-pulled
• self-propelled
• Screener
• Manual labor costs excessive without equipment

6
Windrow Composting, cont.

• Footprint
• One Acre Can Handle 4,000 - 7,000 CY Compost Mix
• Costs
• Site Prep -Site Specific
• Asphalt/Concrete Pad (12 - 27/square yard)
• Equipment
• Grinder/Shredder 3,500
• Tractor/Front End Loader 50K - 150K
• Windrow Turner 30K - 200K
• Screeners 50K - 180K

7
Aerated Compost Bins
8
Aerated Compost Bins

• Aeration Through Porous Floor Plates
• Composting Time 2 - 3 Weeks
• Curing Time 2 Months
• Durable Materials of Construction
• Equipment Needed Front End Loader
• Vector/Vermin Control Needed With Food Wastes
• Capacities 3 - 4 Days Food Waste Bulking Agent
  Per Bin

9
Aerated Compost Bins At Caledonia

• 12 Bins - Two Rows of 6 Bins
• Construction Cost - 40,000
• Footprint - 50 SF per Bin
• Capacity of Each Bin - 36 Barrels (35 - gal.) of
  Food Scraps
• Blowers - 980 CFM
• Aeration Plates - 2 x 2, 89 Each
• Filling/Emptying - With Bobcat

10
Aerated Static Pile

• Aeration Provided By Mechanical Blowers
• Can Shorten Composting time to 3 - 5 Weeks
  (followed by 30 days curing)

11
Aerated Static Pile

• Better Suited to Larger Volumes (landscape debris
  and food waste)
• May Not Be Suited to Wastes That Need Mixing
  During Composting, Like Food Wastes
• Difficult to Adjust Moisture Content During
  Composting If Needed
• Odor Control Difficult With Positive Aeration
• Less Land Area Than Windrows, Still Labor
  Intensive

12
In-Vessel SystemsRotary Drum Composters
13
Rotary Drum Composters

• Rotation Mixes, Aerates Compost Mix
• Second - Stage Curing/Composting Needed
• Food Waste Grinding and Mixing With Bulking Agent
  Needed Prior to Feeding Drum
• Recipe For Drum Composting Food Wastes
• 2 Parts Wood Chips
• 1 Part Sawdust
• 2 Parts Food Waste

14
Rotary Drum Composting at Brown Creek

• Type 616 Greendrum Composter with Patz 9427
  Chopper
• Mounted on Tandem Axle Frame - moveable
• Footprint - 200-300 SF
• Daily Loading Rate - 2,000 - 5,000 Lbs/Day
• Operating Capacity - 11 CY
• Retention Time - 1 Week, Curing Time - 2 Months
• Cost - Approx. 45,000

15
Box/Tunnel Composting Systems
16
Box/Tunnel Composting Systems
17
Auburn Correctional Facility, NY

• Wright Environmental Model 1500 (Model 750 shown)

18
Auburn Correctional Composting

• Capacity 1500 lbs/day
• Composting Time 4 Weeks
• Curing Time 1 Month
• Labor - 2 Inmates
• Cost 123,000
• Disposal Savings 33,000 / yr. (4-yr. Payback)
• Footprint 50 Long x 10 Wide

19
Mechanical Compost Bins

• Green Mountain Technologies Earth Tub
• Modular Design, Batch Operation
• Capacity 200 lbs/day
• Composting Time 4 Weeks Curing 1 Month
• Footprint 1 Parking Space
• Cost 6,000
• Labor 1 Operator

20
GMT Earth Tub Installations

• UNC - Asheville (Spring, 1999)
• Univ. of Georgia
• Hyatt Regency, Chicago
• Vermont DEC
• Univ. of South Carolina
• Connecticut DEP
• Flushing Hospital, NY
• Texas AM University

21
For More Information

• Greendrum Rotary Drum Composter
• Bob Broom, RKB Enterprises [phone]
• Wright Environmental Tunnel System
• Paul Roth, Innovative Environmental Systems
• [phone]
• Green Mountain Technologies Earth Tub
• John DeRham, [phone]

22
Summary

• Factors To Consider In Selecting Technology
• Available Space
• Available Labor (Inmate or Staff)
• Vendor Previous Experience With Same Feedstocks
• Control of Odors, Vermin, and Vectors
• Life - Cycle Costs
• Capital Costs And All OM Costs Over Expected
  Life Of System
• Low - Tech Lower Capital Higher Operating Costs
• High - Tech Higher Capital Lower Operating Costs