Previous Year Question

According to the Environmental Protection Agency, power plants burning fossil fuels are the largest source of sulphur-dioxide emissions.

In particular, sulphur present in coal and high-sulphur oil is oxidized during combustion to form sulphur dioxide.

Therefore, option (d) is the correct answer.

Industrial boilers and other fossil-fuel combustion facilities also emit sulphur dioxide.

Sulphur dioxide may be released from sulphur-bearing minerals during the extraction and smelting of metals from ores.

Ships and locomotives burning high-sulphur fuels also emit it, but among the given options they are not the largest source.

Sulphur dioxide is a colourless gas with a sharp odour and can affect the respiratory system.

It can react in the atmosphere to form sulphate particles, which become part of fine particulate matter or PM2.5.

Sulphur dioxide and its products contribute to the formation of acid rain.

Acid deposition can damage lakes, rivers, soils, forests and aquatic organisms.

It can also accelerate the deterioration of buildings, metals and historical monuments.

Low-sulphur fuels, fuel switching and renewable energy can be used to reduce sulphur-dioxide emissions.

Flue-gas desulphurization systems or scrubbers can remove sulphur dioxide from exhaust gases in power plants.

Emission standards and controls on the sulphur content of fuels are also major measures for reducing its emissions.