Composting is an age old practice of waste management whereby the organic components of the waste streams are biologically decomposed under controlled conditions to a stabilized state that can be safely handled, stored or applied to land as a soil amendment.
Composting can occur in the presence of oxygen referred to as aerobic composting, or in the absence of oxygen referred to as anaerobic composting. Most modern compost systems are aerobic for important reasons.
There are three methods of aerobic composting with the windrow method being the most cost effective.
Methods of Aerobic Composting
The raw materials for composting can be split into two categories: Carbon sources and Nitrogen sources.
| Characteristics of Nitrogen Sources: | Examples of Nitrogen Sources: | |
| Wet | Livestock manure | |
| Decompose quickly | Food waste | |
| High in nitrogen | Grass | |
| High bulk density | ||
| Not very rigid |
| Characteristics of Carbon Sources: | Examples of Carbon Sources: | |
| Dryer | Corn Stalks | |
| Decompose slowly | Leaves | |
| Low in nitrogen | Sawdust | |
| Low bulk density | Wood chips | |
| Somewhat rigid |
Fresh Compost: Has undergone partial decomposition, but it is not stabilized and continues to breakdown.
Mature Compost: Generally suitable as an organic soil conditioner, but is only partially stabilized and may temporarily arrest plant growth if it comes in direct contact with the roots.
Cured Compost: Highly stabilized product, excellent organic soil conditioner
Class A: Includes cured compost, suitable for lawn and garden application, referred to as designer compost
Class B: Includes fresh and mature compost, used as an agronomic soil amendment
| ITEM | %DM | %C | %N |
| Wood chips | 83.08 | 35.84 | 1.27 |
| Grass | 58.39 | 43.99 | 3.79 |
| Leaves | 77.75 | 48.02 | 1.37 |
| Solid Manure | 49.10 | 25.75 | 1.38 |
| Liquid Manure | .5072 |
| pH | %DM | Ash | %N | %C | C:N |
| 7.6 | 64.43 | 67.31 | 1.75 | 18.16 | 11:17 |
Solid Livestock Waste
1.59 lbs. manure: 1 lb. landscape waste
652.0 lbs manure: 1 cu. yd. landscape waste
1.96 tons of raw material to make 1 ton compost
Swine Liquor-Grass
.20 lbs. liquid manure: 1 lb grass
135.59 lbs. liquid manure: 1 cu. yd. grass
1.82 tons raw material to make 1 ton of compost
Compost Process
No. of turns - 11
Days between turns - 5.2
Days from first to last turn - 53
Days to compost - 75
Swine Liquor - Wood Chips
3.19 lbs. liquid manure: 1 lb. wood chips
1592.59 lbs. liquid manure: 1 cu. yd. wood chips
5.78 tons of raw material to make 1 ton of compost
Compost Process
No. of turns - 16
Days between turns - 2.2
Days from first to last turn - 33
Days to compost - 151
Moisture content
Carbon to Nitrogen Ratio
Aeration
Windrows should be turned to accomplish this.
Windrow Turning Frequency:
First 3 - 5 Days: Turn Daily
Next 3 - 4 Weeks: Turn 2 - 3 Times/Week
Week 5 to End: Turn Once/Week
The Illinois EPA, Bureau of Land and Bureau of Water regulates composting and in some instances permits are required.
Permits are not required if:
Permits are required: