Question

Cottrell precipitator acts on which of the following principles?
A. Hardy-Schulze rule
B. Distribution law
C. Le Chatelier’s principle
D. Neutralization of charge on colloidal particles

Answer 1

Hint: Cottrell precipitator is a type of electrostatic precipitator. It is used for the purification of gas. Cottrell precipitator works on the principle of neutralization. It neutralizes the charge on the carbon particles.

Complete step by step solution:
Cottrell precipitator is an electrostatic device used for treating cement mill dust, sulfuric acid mist, power-plant fly ash, metallurgical fumes etc. This precipitator is also called Cottrell smoke precipitator. Smoke is an example of a colloidal solution of solid in gas. It is a mixture of dust, carbon, and arsenic compounds in air. Precipitation of smoke takes place in the Cottrell precipitator. In this precipitator, the charge of the dust particles or carbon is neutralized. This is an electrostatic precipitator.
Principles of electrostatic precipitator are:
Uses electrostatic forces.
Consists of discharge wires and collecting plates.
High voltage is applied to discharge wires to form an electric field between the discharge wires and collecting plates.
When dust particles in smoke flow between the discharge wires and collecting plates, dust particles in the gas are charged by the ions.
Electric field causes a coulomb force which leads the charged particles to collect on the collecting plates and thus the gas is purified.

Additional information:
The major components of electrostatic precipitators are collection electrodes, discharge electrodes, high voltage power supply, precipitator controls, rapping or spray washing systems, purge air systems. Electrostatic precipitators can be designed as either single or two-stage configurations.

Note: Electrostatic precipitators are designed to meet the needs of industries. Some of them are abrasives, oil mist, explosive media, fine powder, welding fumes, etc. The main steps involved in this process are ionization, migration, collection, charge dissipation, particle dislodging, and particle removal.