Control of Particulate Matter Dr. Wesam Al Madhoun
What is Particulate Matter?
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Particulate matter (PM)
describes a wide variety of airborne material.
PM pollution consists of materials (including dust, smoke, and soot), thatare directly emitted into the air or result from the transformation of gaseous pollutants.
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Particles come from natural sources (e.g., volcanic eruptions) and human
activities such as burning fossil fuels, incinerating wastes, and smeltingmetals.
haracteristics of Particles
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The most important characteristic of particulate matter (PM) isthe
particle size
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This property has the greatest impact on the behavior of particulate matter in control equipment, the atmosphere, andthe respiratory tract.
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Particles of importance in air pollution control span a broadsize range from extremely small (0.01 micrometer) to morethan 1,000 micrometers.
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As a frame of reference, a human hair has a diameter of approximately 50 micrometers.
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The chemical composition of the particulate matter is alsoimportant.
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Absorption and heterogeneous nucleation of vapor phasepollutants onto existing particles can create toxic particulatematter.
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Other characteristics besides size and chemical compositionshould be considered when selecting an appropriateparticulate control device for a gas stream.
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Other important characteristics of particulate matter in gasstreams include stickiness and explosiveness.