UPSC Prelims 2019 Question:

In the context of which one of the following are the terms ‘pyrolysis and plasma gasification’ mentioned?

Explanation: 

• Pyrolysis and plasma gasification are waste-to-energy technologies that heat waste materials to high temperature. Like incineration, pyrolysis and plasma gasification are Advanced Thermal Technologies that use  high temperatures to break down waste. The main difference is that they use less oxygen than traditional mass-burn incineration. 
  • The pyrolysis process thermally degrades waste in the absence of air (and oxygen).
  • Gasification is a process in which materials are exposed to some oxygen, but not enough to allow combustion to occur.
    
    
• These processes rely on carbon-based waste such as paper, petroleum-based wastes like plastics, and organic materials such as agricultural residues. The main product of gasification and pyrolysis is syngas (Carbon Monoxide and Hydrogen). Syngas has a calorific value, so it can be used as a fuel to generate electricity or steam i.e. Energy. 
   

Therefore, option (4) is the correct answer.

Subject: Environment | Waste Management