In the context of which one of the following are the terms 'pyrolysis and plasma gasification' mentioned?
- A.Extraction of rare earth elements
- B.Natural gas extraction technologies
- C.Hydrogen fuel-based automobiles
- D.Waste-to-energy technologies
Correct answer
Explanation
The correct answer is D, Waste-to-energy technologies. Pyrolysis and plasma gasification are two thermal methods of turning solid waste into fuel gas, oil or power.
Pyrolysis heats waste such as plastic, tyres or biomass to a high temperature in the absence of oxygen, so it breaks down into pyrolysis oil, a fuel gas called syngas and a solid char instead of burning. Plasma gasification uses an electric arc that creates plasma at several thousand degrees Celsius; it breaks organic waste into syngas (mainly hydrogen and carbon monoxide) and melts the rest into a glassy slag that can be used in construction. Both cut the volume of waste sent to landfills and recover energy from it.
A is wrong: rare earth elements are obtained by mining and chemical separation of ores such as monazite.
B is wrong: natural gas is extracted by drilling, and from shale by hydraulic fracturing.
C is wrong: hydrogen vehicles use fuel cells; they do not depend on these waste processes.
Exam tip: pyrolysis = heat without oxygen; plasma gasification = plasma arc to syngas + slag; both = waste to energy.
Practice Questions
View allOne carbon credit is accepted as equivalent to
- A.100 kg of carbon
- B.100 kg of carbon dioxide
- C.1000 kg of carbon
- D.1000 kg of carbon dioxide
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One carbon credit stands for one tonne of carbon dioxide, or its equivalent in other greenhouse gases, kept out of the atmosphere.
Read the full explanation →Which one among the following reports defines Sustainable Development as development that meets the needs of the present generation without compromising the ability of future generations to meet their own needs?
- A.Brundtland Report
- B.United Nations Human Development Report
- C.Agenda-21 of the Rio Earth Summit
- D.OECD Policy Brief (2006)
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This 1987 report gave the world the standard definition of sustainable development quoted in the question. The report, titled Our Common Future, was prepared by the World Commission on Environment and Development, set up by the United Nations in 1983.
Read the full explanation →The 'Ramsar Convention' relates to which one of the following areas ?
- A.Wetland preservation
- B.Promote afforestation
- C.Action plan on climate change
- D.Combat desertification
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The Ramsar Convention is the international treaty for the conservation and wise use of wetlands. It was signed on 2 February 1971 at Ramsar, a town in Iran on the Caspian Sea, and came into force in 1975.
Read the full explanation →A new species of pit-viper was discovered in 2019 and named after the State in which it was found. Identify the State from among the following :
- A.Kerala
- B.Arunachal Pradesh
- C.Andaman and Nicobar Islands
- D.Assam
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The species was named Trimeresurus arunachalensis, the Arunachal pit viper, after the state where it was found. Pit vipers are venomous snakes with a heat-sensing pit between each eye and nostril, which lets them detect warm-blooded prey in the dark.
Read the full explanation →Cheetahs were recently re-introduced to India from Africa. From which language is the name 'Cheetah' derived ?
- A.Swahili
- B.Afrikaans
- C.Somali
- D.Sanskrit
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The word comes from the Sanskrit 'chitraka', meaning the spotted or speckled one, and reached English through the Hindi 'cheeta'.
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