Composting is the controlled decomposition of organic materials through microbial activity under aerobic conditions, producing a stable end product called compost. The process requires a balance of carbon and nitrogen, as well as sufficient oxygen, water, and temperature between 40-55°C. Organic materials like leaves and straw provide carbon, while materials like food scraps and grass clippings supply nitrogen. Microorganisms like bacteria, fungi, and earthworms drive the breakdown of materials. Composting can be aerobic, anaerobic, or use earthworms, and has advantages like waste diversion, pathogen removal, and soil conditioning.

1. Composting
• “The Biological Decomposition and stabilization
of organic substrates under aerobic conditions ,
with a final product sufficiently stable for storage
and application to land without adverse
environmental effects”.
• Controlled Decomposition of Organic Materials
• Slow, Exothermic & Microbial Process
• End Product Stable Residue (Compost)

3. Factors Effecting Composting
• Carbon
• Nitrogen - C/N ratio is 30:1
• Oxygen
• Water – 40-60%
• Size – 3 feet wide, deep & tall
• Temperature – 40-55°C

4. Types of Material
• 'Browns' are dry and dead plant materials such as
straw, dry brown weeds, leaves and twigs.
• Browns are a source of carbon and energy for
compost microbes.
• 'Greens' are fresh plant materials such as green leaves
and garden clippings, kitchen, fruit and vegetable
scraps, coffee grounds, tea bags, etc.
• Compared to browns, greens contain more nitrogen
which is a critical element in amino acids and proteins.
• So greens can be thought of as a protein source for
the billions of multiplying microbes.

5. Microorganisms
• Bacteria-.
• Actinomycetes-
• Fungi-
• Protozoa-
• Rotifers-
• Earth worms

6. Types of Composting
1. Aerobic composting (composting with air – in
the presence of oxygen)
Organic materials + oxygen + water = carbon
dioxide + water + energy
2. Anaerobic composting (composting without air
– in sealed spaces)
Organic materials + water = carbon dioxide +
methane + hydrogen sulfide + energy
3. Vermicomposting (composting that is speeded
up by earthworms)

7. Advantages of Compost
• Destroying pathogens, seeds, or unwanted
plants
• Helps in diverting waste from landfills, water
ways ,water treatment plants & Environment
• No waste production
• Compost can be used as Soil Conditioner
• Economical

8. Composting systems
• One bin systems
• Two bin and three bin systems
• Sheet/ Trench composting system
• Commercially available bin systems