Solid Waste Management MCQ with answer and solution

Concept

Energy is recovered from solid waste by thermal processes: combustion (with excess air) and pyrolysis (without oxygen).

Step-by-step solution

1. Energy recovery from solid waste uses thermal conversion. 2. Combustion (incineration) burns waste in excess air and gives heat to make steam or power. 3. Pyrolysis heats waste without oxygen and gives fuel gas, oil and char. 4. So the two processes are combustion and pyrolysis. Answer is (C).

Explanation

The two main energy recovery processes for solid waste are combustion and pyrolysis. Combustion burns the waste with oxygen and gives heat. Pyrolysis breaks the waste down by heat without oxygen and gives useful fuels.

Why the other options are wrong

A: Exothermic is a general type of reaction, not a separate recovery process (combustion is itself exothermic). B: Endothermic is a reaction type, not a recovery process. D: Exothermic is a reaction type, not a named recovery process.

Shortcut

With oxygen = combustion; without oxygen = pyrolysis. Both recover energy.

Common mistake

Confusing reaction types (exothermic/endothermic) with process names.