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Air Pollution Control Devices

After the Clean Air Act was passed in 1971, businesses in America awakened to the need for reduced air pollution in plants and factories. New technologies led to the development of devices that work to reduce the size, weight and amount of solid particles and chemical gases in the air, the speed at which these particles and gases move, their density and their solubility. The goal of these devices is to purify the air by separating pollutants from oxygen to create better quality air.

  1. Electrostatic Precipitator

    • This is an air purifier that lets you clean the air circulating within your home or office using electronic cells that can be washed. The electronic cells come in magnetically charged strips of metal that collect airborne particles. When the air enters the electrostatic precipitator, the particles it carries pass through an electrical field that charges the particles. The charged particles then pass through a set of alternately charged aluminum collector plates and are attracted to the plates that have an opposing polarity to the type of particle being filtered. In dual-stage electrostatic precipitators, the positively charged contaminants are collected on the negatively charged plates. This removes smoke, grease, mist and other polluting particles from the air stream.

    Cyclone Dust Collectors

    • Cyclone dust collectors are the most commonly used type of inertial separators -- machines that use gravity and inertia to separate particles from the air stream. Inertial separators slow the speed of dust-filled airflow, so the heavier dust particles settle and fall into a hopper. Taking its name from the cyclone weather phenomenon, cyclone dust collectors have enclosed funnel-shaped tubes made of sheet metal with a cyclone-like vortex that travels down the tube. These tubes are attached to ducts that are often found in manufacturing plants, processing plants and woodshops. The dust- and debris-filled air is sucked in at the top. The purified air is expelled from the other side of the top while the dust and debris falls out into a bin where it is collected. Cyclone dust collectors come in a range of sizes for home or industrial use.

    Catalytic Oxidizers

    • Use at manufacturing plants and sites that consistently emit volatile organic compounds, catalytic oxidizers draw VOC-laden air into a system fan and discharge it into the equipment's heat exchanger. The air is preheated as it travels through the tube side of the heat exchanger. It then passes through a burner where the temperature of the air is raised. The heat converts the VOCs in the air into carbon dioxide and water vapor. The heated, purified air is then expelled on the shell side of the heat exchanger and released into the atmosphere. Catalytic oxidizers are not ideal for purifying air that contain solid particulates, as these may coat the inside of the equipment, rendering it less efficient in breaking down VOCs.

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