Food Waste Diversion atFood Waste Diversion at Correctional Facilities Correctional Facilities

Composting Technologies and CostsComposting Technologies and Costs

Craig CokerCraig Coker

Organics Recycling CoordinatorOrganics Recycling Coordinator

DENR/ Div. Of Pollution Prevention & DENR/ Div. Of Pollution Prevention & Environmental AssistanceEnvironmental Assistance

OverviewOverview

Technology in Composting Technology in Composting • Materials HandlingMaterials Handling• Biological Process OptimizationBiological Process Optimization• Odor ControlOdor Control

Capital CostCapital Cost• Increases with technologyIncreases with technology

Operational CostsOperational Costs• Decrease with technologyDecrease with technology

Footprint (Area Required)Footprint (Area Required)• Decreases with technology (usually)Decreases with technology (usually)

Technology ClassificationTechnology Classification

Low - TechLow - Tech• WindrowWindrow

Mid - TechMid - Tech• Aerated Static PileAerated Static Pile• Aerated Compost BinsAerated Compost Bins

High - Tech (In-Vessel)High - Tech (In-Vessel)• Rotary Drum CompostersRotary Drum Composters• Box/Tunnel Composting SystemsBox/Tunnel Composting Systems• Mechanical Compost BinsMechanical Compost Bins

Windrow CompostingWindrow Composting

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

Windrow Composting, cont.Windrow Composting, cont.

Equipment NeededEquipment Needed• Grinder/ShredderGrinder/Shredder• Tractor/FELTractor/FEL• Windrow TurnerWindrow Turner

– tractor-pulledtractor-pulled– self-propelledself-propelled

• ScreenerScreener Manual labor costs Manual labor costs

excessive without excessive without equipmentequipment

Windrow Composting, cont.Windrow Composting, cont.

FootprintFootprint• One Acre Can Handle 4,000 - 7,000 CY One Acre Can Handle 4,000 - 7,000 CY

Compost MixCompost Mix CostsCosts

• Site Prep -Site SpecificSite Prep -Site Specific• Asphalt/Concrete Pad ($12 - $27/square yard)Asphalt/Concrete Pad ($12 - $27/square yard)• EquipmentEquipment

– Grinder/Shredder : $3,500Grinder/Shredder : $3,500– Tractor/Front End Loader : $50K - $150KTractor/Front End Loader : $50K - $150K– Windrow Turner : $30K - $200KWindrow Turner : $30K - $200K– Screeners : $50K - $180KScreeners : $50K - $180K

Aerated Compost BinsAerated Compost Bins

Aerated Compost BinsAerated Compost Bins

Aeration Through Porous Floor PlatesAeration Through Porous Floor Plates Composting Time: 2 - 3 WeeksComposting Time: 2 - 3 Weeks Curing Time: 2 MonthsCuring Time: 2 Months Durable Materials of ConstructionDurable Materials of Construction Equipment Needed: Front End LoaderEquipment Needed: Front End Loader Vector/Vermin Control Needed With Food Vector/Vermin Control Needed With Food

WastesWastes Capacities: 3 - 4 Days Food Waste + Capacities: 3 - 4 Days Food Waste +

Bulking Agent Per BinBulking Agent Per Bin

Aerated Compost Bins At Aerated Compost Bins At CaledoniaCaledonia

12 Bins - Two Rows of 6 Bins12 Bins - Two Rows of 6 Bins Construction Cost - $40,000Construction Cost - $40,000 Footprint - 50 SF per BinFootprint - 50 SF per Bin Capacity of Each Bin - 36 Barrels (35 - Capacity of Each Bin - 36 Barrels (35 -

gal.) of Food Scrapsgal.) of Food Scraps Blowers - 980 CFMBlowers - 980 CFM Aeration Plates - 2’ x 2’, $89 EachAeration Plates - 2’ x 2’, $89 Each Filling/Emptying - With BobcatFilling/Emptying - With Bobcat

Aerated Static PileAerated Static Pile

Aeration Provided By Mechanical BlowersAeration Provided By Mechanical Blowers Can Shorten Composting time to 3 - 5 Weeks Can Shorten Composting time to 3 - 5 Weeks

(followed by 30 days curing)(followed by 30 days curing)

Aerated Static PileAerated Static Pile

Better Suited to Larger Volumes (landscape Better Suited to Larger Volumes (landscape debris and food waste) debris and food waste)

May Not Be Suited to Wastes That Need May Not Be Suited to Wastes That Need Mixing During Composting, Like Food WastesMixing During Composting, Like Food Wastes

Difficult to Adjust Moisture Content During Difficult to Adjust Moisture Content During Composting If NeededComposting If Needed

Odor Control Difficult With Positive AerationOdor Control Difficult With Positive Aeration Less Land Area Than Windrows, Still Labor Less Land Area Than Windrows, Still Labor

IntensiveIntensive

In-Vessel SystemsIn-Vessel SystemsRotary Drum CompostersRotary Drum Composters

Rotary Drum CompostersRotary Drum Composters

Rotation Mixes, Aerates Compost MixRotation Mixes, Aerates Compost Mix Second - Stage Curing/Composting NeededSecond - Stage Curing/Composting Needed Food Waste Grinding and Mixing With Food Waste Grinding and Mixing With

Bulking Agent Needed Prior to Feeding DrumBulking Agent Needed Prior to Feeding Drum Recipe For Drum Composting Food Wastes:Recipe For Drum Composting Food Wastes:

• 2 Parts Wood Chips2 Parts Wood Chips• 1 Part Sawdust1 Part Sawdust• 2 Parts Food Waste2 Parts Food Waste

Rotary Drum Composting Rotary Drum Composting at Brown Creekat Brown Creek

Type 616 Greendrum Composter with Patz Type 616 Greendrum Composter with Patz 9427 Chopper9427 Chopper

Mounted on Tandem Axle Frame - moveableMounted on Tandem Axle Frame - moveable Footprint - 200-300 SFFootprint - 200-300 SF Daily Loading Rate - 2,000 - 5,000 Lbs/DayDaily Loading Rate - 2,000 - 5,000 Lbs/Day Operating Capacity - 11 CYOperating Capacity - 11 CY Retention Time - 1 Week, Curing Time - 2 Retention Time - 1 Week, Curing Time - 2

MonthsMonths Cost - Approx. $45,000 Cost - Approx. $45,000

Box/Tunnel Composting Box/Tunnel Composting SystemsSystems

Box/Tunnel Composting Box/Tunnel Composting SystemsSystems

Auburn Correctional Facility, Auburn Correctional Facility, NYNY

Wright Environmental Model 1500 Wright Environmental Model 1500 (Model 750 (Model 750 shown)shown)

Auburn Correctional Auburn Correctional CompostingComposting

Capacity: 1500 lbs/dayCapacity: 1500 lbs/day Composting Time: 4 WeeksComposting Time: 4 Weeks Curing Time: 1 MonthCuring Time: 1 Month Labor - 2 InmatesLabor - 2 Inmates Cost: $123,000Cost: $123,000 Disposal Savings: $33,000 / yr. (4-yr. Disposal Savings: $33,000 / yr. (4-yr.

Payback)Payback) Footprint: 50’ Long x 10’ WideFootprint: 50’ Long x 10’ Wide

Mechanical Compost BinsMechanical Compost Bins

Green Mountain Green Mountain Technologies “Earth Technologies “Earth Tub”Tub”

Modular Design, Batch Modular Design, Batch OperationOperation

Capacity: 200 lbs/dayCapacity: 200 lbs/day Composting Time: 4 Composting Time: 4

Weeks; Curing: 1 MonthWeeks; Curing: 1 Month Footprint: 1 Parking Footprint: 1 Parking

SpaceSpace Cost: $6,000Cost: $6,000 Labor: 1 OperatorLabor: 1 Operator

GMT “Earth Tub” InstallationsGMT “Earth Tub” Installations

UNC - Asheville UNC - Asheville (Spring, 1999)(Spring, 1999)

Univ. of GeorgiaUniv. of Georgia Hyatt Regency, Hyatt Regency,

ChicagoChicago Vermont DECVermont DEC Univ. of South CarolinaUniv. of South Carolina Connecticut DEPConnecticut DEP Flushing Hospital, NYFlushing Hospital, NY Texas A&M UniversityTexas A&M University

For More Information:For More Information:

Greendrum Rotary Drum ComposterGreendrum Rotary Drum Composter• Bob Broom, RKB Enterprises (888) 475-Bob Broom, RKB Enterprises (888) 475-

23682368 Wright Environmental Tunnel SystemWright Environmental Tunnel System

• Paul Roth, Innovative Environmental Paul Roth, Innovative Environmental Systems Systems

(757)890-1354(757)890-1354 Green Mountain Technologies Earth TubGreen Mountain Technologies Earth Tub

• John DeRham, (802) 368-7291John DeRham, (802) 368-7291

SummarySummary

Factors To Consider In Selecting TechnologyFactors To Consider In Selecting Technology• Available SpaceAvailable Space• Available Labor (Inmate or Staff)Available Labor (Inmate or Staff)• Vendor Previous Experience With Same Vendor Previous Experience With Same

FeedstocksFeedstocks• Control of Odors, Vermin, and VectorsControl of Odors, Vermin, and Vectors• Life - Cycle CostsLife - Cycle Costs

– Capital Costs And All O&M Costs Over Expected Life Of Capital Costs And All O&M Costs Over Expected Life Of SystemSystem

– Low - Tech: Lower Capital; Higher Operating CostsLow - Tech: Lower Capital; Higher Operating Costs– High - Tech: Higher Capital; Lower Operating CostsHigh - Tech: Higher Capital; Lower Operating Costs