In pollution control technology, an electrostatic precipitator installed in an industrial plant is primarily used to control which type of environmental pollution?

Introduction / Context:
This question tests your understanding of a common device used to control industrial pollution: the electrostatic precipitator. Large power plants, cement factories, steel plants and similar industries often release fine particulate matter in their flue gases. If not controlled, these particles cause serious air pollution and health problems. Knowing which type of pollution electrostatic precipitators target helps you link basic physics of electrostatics with real world environmental protection measures.

Given Data / Assumptions:

• An electrostatic precipitator is installed in an industrial setting.
• It uses electric fields to remove particles from gas streams.
• The options include water, noise, air pollution and solid waste.
• We assume a typical flue gas cleaning application in chimneys or exhaust ducts.

Concept / Approach:
An electrostatic precipitator works by charging fine dust and smoke particles as they pass through a region of strong electric field between high voltage electrodes and collecting plates. The charged particles are attracted to oppositely charged plates and get deposited on them, leaving the cleaned gas to exit the chimney. This process directly targets airborne particulate pollutants such as ash, soot and smoke in exhaust gases and significantly reduces air pollution. It does not treat water, reduce noise or manage solid waste on land, although it indirectly reduces solid particulate emissions into the atmosphere.

Step-by-Step Solution:
Step 1: Recall that electrostatic precipitators are usually mounted in the exhaust system of power plants and industrial furnaces. Step 2: Recognise that hot flue gases leaving a boiler contain fine solid particles like fly ash and dust. Step 3: Understand that in an electrostatic precipitator, these particles are electrically charged and then attracted to collecting plates, effectively removing them from the gas stream. Step 4: The cleaned gas, with most of the particulates removed, is then released into the atmosphere through the chimney, reducing air pollution. Step 5: Since the device acts on gases and suspended particles, it directly addresses air pollution rather than water, noise or land based solid waste.

Verification / Alternative check:
To verify, think about what types of pollution the other options refer to. Water pollution control uses treatment plants, filters, sedimentation tanks and chemical treatments, not electrostatic precipitators. Noise pollution is managed by silencers, acoustic barriers and insulation. Solid waste on land is handled by landfills, recycling and incinerators. Electrostatic precipitators specifically appear in diagrams of thermal power plant chimneys and are always mentioned in the context of reducing smoke and dust emissions into the air, confirming that they are air pollution control devices.

Why Other Options Are Wrong:
Water pollution is not treated by electrostatic precipitators; these devices are designed for gases, not liquids. Noise pollution is unrelated to charged dust removal; electrostatic precipitators do not significantly reduce sound levels. Solid waste on land is handled by different methods such as landfills and recycling facilities, not by passing waste through electric fields in chimneys.

Common Pitfalls:
Students sometimes confuse the term precipitator with precipitation in water treatment and incorrectly link it to water pollution. Others may not recall the exact positioning of the device in power plant diagrams. To avoid confusion, remember that electrostatic precipitators are located in the path of exhaust gases and rely on electrostatics to pull out suspended particles, which clearly identifies them as instruments for controlling air pollution.

Final Answer:
An electrostatic precipitator is primarily used to control air pollution by removing particulate matter from exhaust gases.