Question

Which of the following is a common aerobic process for the stabilization of solid wastes?

• A. Incineration
• B. Composting
• C. Landfilling
• D. Pyrolysis

Hint:

• Composting Aerobic decomposition of organic waste by microorganisms.
• Anaerobic Digestion Decomposition of organic waste by microorganisms in the absence of oxygen (produces biogas).
• Incineration High-temperature combustion (thermal, requires oxygen).
• Pyrolysis Thermal decomposition in the absence of oxygen.
• Landfilling Disposal method, primarily anaerobic decomposition occurs over time.

Answer 1

The Correct Option is B

Stabilization of solid wastes refers to processes that reduce the volume, toxicity, or reactivity of the waste, often by decomposing organic matter.

• (a) Incineration: A thermal process involving combustion of waste at high temperatures. It significantly reduces volume and can generate energy, but it is a combustion process, not primarily a biological stabilization method focused on decomposition by microbes. It can be aerobic in terms of combustion.
• (b) Composting: A biological process where organic solid wastes (e.g., food scraps, yard waste) are decomposed by aerobic microorganisms (bacteria, fungi, actinomycetes) under controlled conditions of moisture, aeration, and temperature. The end product is compost, a stable, humus-like material beneficial for soil. This is a common aerobic stabilization process.
• (c) Landfilling: Disposal of solid waste by burying it in land. Decomposition in landfills is largely anaerobic (especially in deeper layers), leading to methane production. It is a disposal method, and some stabilization occurs, but it's not primarily a controlled aerobic stabilization process.
• (d) Pyrolysis: A thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen (or with very limited oxygen). It produces gas, liquid (bio-oil), and solid (char) products. It is an anaerobic thermal process.

Among the options, composting is the most common aerobic biological process specifically designed for the stabilization of organic solid wastes. \[ \boxed{\text{Composting}} \]