SSC Stenographer 2026 – 10 September 2026 Shift 1 · Waste management and biodegradable substances
Q1. Which of the following best explains why pyrolysis is considered a more sustainable method for managing plastic waste compared to traditional incineration or landfilling?
- (a) Pyrolysis requires higher oxygen levels and generates more CO2 than incineration, thus enabling faster decomposition.
- (b) Pyrolysis transforms plastic waste into reusable gases, oils, and char without combustion, thereby reducing greenhouse gas emissions.
- (c) Pyrolysis converts plastic into biodegradable polymers that can be reused directly in agriculture.
- (d) Pyrolysis reduces plastic volume by 90% through combustion, producing energy-intensive ash used in road construction.
Answer & solution
Answer: (b) Pyrolysis transforms plastic waste into reusable gases, oils, and char without combustion, thereby reducing greenhouse gas emissions.
Answer: Option 2 — Pyrolysis transforms plastic waste into reusable gases, oils, and char without combustion, thereby reducing greenhouse gas emissions.
Pyrolysis heats plastic in the absence of oxygen, so the waste breaks down instead of burning.
The products — syngas, pyrolysis oil and char — are recovered as fuel and feedstock, which is why the route emits far less than open burning.
Revision note — Pyrolysis and plastic waste management
• Pyrolysis is the thermal decomposition of organic matter at about 300–900 degree C in the absence of oxygen — no flame, no combustion.
• Its three products are pyrolysis oil, syngas and solid char; plastic-to-fuel plants run on exactly this process.
• Incineration burns waste with excess oxygen and releases CO2, dioxins and furans.
• Gasification sits between the two — a limited, controlled supply of oxygen or steam converts the waste to syngas.
• Plastic is the commonest non-biodegradable waste because microorganisms cannot break the synthetic polymer down; no heat treatment turns it into a biodegradable polymer.
• India's Plastic Waste Management Rules, 2016 brought in Extended Producer Responsibility (EPR), and identified single-use plastic items were banned from 1 July 2022.
• The theme of World Environment Day 2025 was Ending Plastic Pollution, marked by the campaign One Nation, One Mission: End Plastic Pollution.
• In the 3Rs, reduce means using less, reuse means using an item again, and recycle means reprocessing waste into new products.
Do not mix these up
• Pyrolysis vs incineration — pyrolysis needs no oxygen and recovers fuel; incineration burns the waste in excess oxygen.
• Pyrolysis vs gasification — gasification admits a small, measured amount of oxygen or steam; pyrolysis admits none.
Also asked from this topic: the commonest non-biodegradable waste (plastic); the 2025 plastic campaign (One Nation, One Mission: End Plastic Pollution).
Pyrolysis heats plastic in the absence of oxygen, so the waste breaks down instead of burning.
The products — syngas, pyrolysis oil and char — are recovered as fuel and feedstock, which is why the route emits far less than open burning.
Revision note — Pyrolysis and plastic waste management
• Pyrolysis is the thermal decomposition of organic matter at about 300–900 degree C in the absence of oxygen — no flame, no combustion.
• Its three products are pyrolysis oil, syngas and solid char; plastic-to-fuel plants run on exactly this process.
• Incineration burns waste with excess oxygen and releases CO2, dioxins and furans.
• Gasification sits between the two — a limited, controlled supply of oxygen or steam converts the waste to syngas.
• Plastic is the commonest non-biodegradable waste because microorganisms cannot break the synthetic polymer down; no heat treatment turns it into a biodegradable polymer.
• India's Plastic Waste Management Rules, 2016 brought in Extended Producer Responsibility (EPR), and identified single-use plastic items were banned from 1 July 2022.
• The theme of World Environment Day 2025 was Ending Plastic Pollution, marked by the campaign One Nation, One Mission: End Plastic Pollution.
• In the 3Rs, reduce means using less, reuse means using an item again, and recycle means reprocessing waste into new products.
Do not mix these up
• Pyrolysis vs incineration — pyrolysis needs no oxygen and recovers fuel; incineration burns the waste in excess oxygen.
• Pyrolysis vs gasification — gasification admits a small, measured amount of oxygen or steam; pyrolysis admits none.
Also asked from this topic: the commonest non-biodegradable waste (plastic); the 2025 plastic campaign (One Nation, One Mission: End Plastic Pollution).