1. Composting Technologies and Costs
Minggu 7

2. Overview Technology in Composting Capital Cost Operational Costs
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: 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 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: Weeks
Curing Time: 2 Months
Durable Materials of Construction
Equipment Needed: Front End Loader
Vector/Vermin Control Needed With Food Wastes
Capacities: 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 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 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 Systems Rotary 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 SF
Daily Loading Rate - 2, ,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

21. 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 O&M Costs Over Expected Life Of System
Low - Tech: Lower Capital; Higher Operating Costs
High - Tech: Higher Capital; Lower Operating Costs