Organic Waste For Composting – Organic waste is a major global concern. Solutions to manage it can vary from landfills and incineration, yet the decomposition of organic waste with biological processes, such as composting, is viewed as more appropriate. Composting relies on microbial activity and physical-chemical parameters like temperature, aeration, and moisture content are essential to this process. It is a cost-effective form of solid waste management (SWM), allowing for the recycling of organic materials into useful products.

What is Composting?

Composting is a natural process that transforms organic waste into nutrient-rich soil amendment called compost. It involves the decomposition of various organic materials, such as food scraps, yard trimmings, leaves, and even paper products. Through the action of microorganisms like bacteria, fungi, and worms, these materials break down over time to create a dark and crumbly substance that is highly beneficial for plants.

Composting Process

Composting of agricultural and municipal solid waste is a longstanding practice for recycling organic matter back into the soil, thereby sustaining soil fertility. This activity has seen an increase in recent times due to its environmentally sound qualities. It is a biological process carried out aerobically by naturally occurring microorganisms and creates a humus-like product. Composting has numerous benefits; for example, it eliminates pathogens, converts N from unstable ammonia to sturdier organic forms, and reduces the volume of waste as well as its toxicity; furthermore, it renders waste more convenient to handle and transport while enabling higher application rates due to the slowly released N contained in compost. The efficacy of this process is dependent upon temperature, oxygen level, and humidity.

Types of composting

There are two fundamental types of composting.

1. Aerobic composting is a decomposition process of organic materials with oxygen present. It requires constituents like CO2, NH3, water, and heat to be effective. The right conditions in terms of moisture (60-70%) and Carbon to Nitrogen ratio (30/1) are necessary for optimal degradation. Wood and paper are sources of carbon while sewage sludge and food waste supply nitrogen; ventilation (either active or passive) of the waste is essential to maintain an adequate oxygen flow.

• Anaerobic composting: During anaerobic composting, organic wastes decompose in the absence of oxygen, resulting in methane (CH4), CO2, and NH3, as well as trace amounts of other gases and organic acids. In the past, anaerobic composting was used to compost animal manure and human sewage sludge, but it is now increasingly commonly used for municipal solid waste (MSW) and green waste as well.

Benefits of composting

1. Healthier plants.

2. Composting is practical and convenient.

3. Composting saves money.

4. Composting is a good alternative to landfilling