Which of the following are some important pollutants released by steel industry in India? 1. Oxides of sulphur 2. Oxides of nitrogen 3. Carbon monoxide 4. Carbon dioxide Select the correct answer using the code given below.
- (a) 1, 3 and 4 only
- (b) 2 and 3 only
- (c) 1 and 4 only
- (d) 1, 2, 3 and 4 ✓ UPSC's answer
Why the answer is (d)
• Steel-making burns coke and uses sulphur-bearing coal and ore, releasing sulphur oxides (1); high-temperature furnaces produce nitrogen oxides (2); coke ovens and blast furnaces emit carbon monoxide (3); and the whole process is a major source of carbon dioxide (4) — steel accounts for about 7–9% of global CO2.
• Particulate matter and dust are also significant.
• Hence 1, 2, 3 and 4, option (d).
Why the other options are wrong
- (a) 1, 3 and 4 only
- Nitrogen oxides are also released.
- (b) 2 and 3 only
- Sulphur oxides and CO2 are also released.
- (c) 1 and 4 only
- NOx and CO are also released.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2014, held on 24 August 2014. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.