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)

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

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.

Microorganisms

• Bacteria-.

• Actinomycetes-

• Fungi-

• Protozoa-

• Rotifers-

• Earth worms

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)

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

Composting systems

• One bin systems

• Two bin and three bin systems

• Sheet/ Trench composting system

• Commercially available bin systems