components for successful compost facility operations scap biosolids committee meeting august 2,...
TRANSCRIPT
COMPONENTS FOR SUCCESSFUL COMPOST FACILITY OPERATIONSSCAP Biosolids Committee Meeting
August 2, 2012
page 2
AGENDA
• Facility Siting Considerations• Composting Technologies• Permitting• Regulatory Compliance• Process Control• Compost Quality
page 3
FACILITY SITING CONSIDERATIONS
• Location, Location, Location!– Regulations– Nearby Compost Market– Sensitive Receptors
• Public Education/Politics– Education Begins Early– Keep it Simple– Remember the Benefits
• Diversion• Soil Enhancement• Erosion Control
– Don’t ignore the public/politics
page 4
COMPOSTING TECHNOLOGY
• Windrow• Negative Aerated Static Pile with
Biofiltration• In-vessel
page 5
COMPOSTING TECHNOLOGY: Negative Aerated Static Pile Composting
page 6
COMPOSTING TECHNOLOGY: Negative Aerated Static Pile Composting
page 7
PERMITTING
• Local Conditional Use Permit• CEQA• CA Solid Waste Facility Permit
– Report of Compost Site Information– Odor Impact Minimization Plan
• Regional Water Quality Control Board• Local Air District Permit• U.S. EPA Registration
page 8
REGULATORY
• Inbound Materials Monitoring– Biosolids– Carbon Feedstocks
• Process Water Management• Ground Water Monitoring• Special Occurrences• Source Testing
• Compost Sampling – C.C.R. Title 14, Chapter 3.1, Article 7
• Metals Concentrations (max)• Pathogen Reduction (PFRP) • Sampling Requirements
page 9
PROCESS CONTROL PARAMETERS
• Control Points– Feedstock Handling– Mix Ratios– Moisture– Aeration Rates– Temperature/PFRP
page 10
THE COMPOSTING PROCESS
Feedstocks
Microorganisms
Oxygen
Water
Compost
CO2Water
Odors?
Heat
page 11
COMPOST FACILITY FEEDSTOCK-PROCESS-MARKET
Identify and quantify
Feedstocks
Analyze Markets
Develop and adjust recipes
Collect or receive feedstocks
Process:Grind, Mix, Compost,
Cure, Screen, etc.
Market and distribute
AssessCompost Facility
Start here or
here
page 12
THE KEY PROCESS VARIABLES for Control of the Composting Process
1. Initial feedstock mix
2. Pile moisture
3. Pile aeration
4. Pile shape and size
5. Pile temperature
6. Composting retention time
page 13
FEEDSTOCKS: YOUR RAW MATERIAL
• Chemical Composition– Organic Matter, Nutrients, Degradability
• Physical Characteristics– Moisture, Bulk density, Heterogeneity
• Other– Contamination, Cost, Availability, Regulations
page 14
FEEDSTOCK SUMMARY
• Each feedstock has certain attributes• The RECIPE is how feedstocks are combined• Composting system designed for feedstocks• Regulations are always partly based on feedstock
page 15
OTHER CONSIDERATIONS
• Health & Safety• Initial Mix Ratios• Moisture• Aeration• Temperature• Time• Curing/Maturity• Testing
page 16
SUMMARY: Key Initial Parameters for Composting
Condition Reasonable range Preferred range Moisture % 40 — 65 50 — 60 C:N 20:1 — 60:1 25:1 — 40:1 Oxygen % Greater than 5 Greater than 10 Temperature oF oC
113 — 160 45 -- 71
120 — 150 49 -- 66
pH 5.5 — 9.0 6.5 — 8.0 Particle size 1/8 to 2 inches
.3-5 cm Depends on feedstocks
and use for compost
Porosity: Bulk density lbs/ yd3
(kg/l)
Free Air Space %
Less than 1200
(.7) 40-60
800-1000 (.45-.6) 50-60
