Atmospheric particulate matter
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This document discusses particulate matter (PM), which includes a mixture of solid and liquid particles suspended in the air, highlighting its sources, types, and impacts on human health and the environment. It categorizes PM sources into mechanical, chemical, and biological origins, detailing both natural and human activity contributions. It also outlines health symptoms associated with PM exposure and enumerates methods for controlling particulate emissions.
Atmospheric particulate matter
- 1. RABIA AZIZ BS-III CHEMISTRY 5/31/2017 1RABIA AZIZ
- 2. CONTENTS Introduction Sources Of Particulate Matter Industrial Sources of Particulate Emissions Types Of Particulate Matter Important Terms Describing Atmospheric Particles Particulate Matter And Health General Methods For Control Of Particulate Emissions Particulate Collection Mechanism 5/31/2017 2RABIA AZIZ
- 3. Introduction Particulate matter is a mixture of solid, liquid or solid and liquid particles suspended in the air. These suspended particles vary in size, composition and origin. This complex mixture includes both organic and inorganic particles, such as dust, pollen, soot, smoke, and liquid droplets. Sources of particulate matter can be man-made or natural. They have impacts on climate and precipitation that adversely affect human health. Particulate matter makes up the most visible and obvious form of air pollution. Pollutant particles in the 0.001–10 mm range are commonly suspended in the air near sources of pollution such as the urban atmosphere, industrial plants, highways, and power plants. 5/31/2017 3RABIA AZIZ
- 5. Particles Differ In Their Chemical Composition Depending On Origin. They Are Usually Made Up Of: salts in the form of nitrates, sulphates, carbonates, chlorides, etc., organic carbon compounds (PAHs, oxides, condensable organic compounds, etc.) (called "organic carbon" and written as OC). trace elements such as heavy metals, etc., black carbon (BC). 5/31/2017 5RABIA AZIZ
- 7. Particles are distinguished by size: Total Suspended Particles include all particles, of whatever size, PM10 are particles less than 10 µm (10 microns) in diameter, PM2.5 are particles less than 2.5 µm in diameter, Black Carbon emissions are based on a chemical speciation of PM2,5 emissions PM1.0 are particles less than 1 µm in diameter, Particles which are 2.5 to 10 in diameter are called coarse particles. Particles less than 2.5 in diameter are called fine particles and include ultra-fine particles of less than 0.1 µm (PM0.1). 5/31/2017 7RABIA AZIZ
- 8. coarse particles Fine particles Ultra-fine particles 5/31/2017 8RABIA AZIZ
- 9. Sources of Particulate matter Particulate matter emissions are generated from different sources: Mechanical: powdering, crushing, cracking, transport of non- cohesive materials, soil erosion (by wind for example), etc. These particles are usually a few microns to a few hundred microns in diameter. Chemical or thermal: These particles form when chemical reactions or high-temperature evaporation followed by condensation change the state of the material. These particles range in size from a few nanometres to under 1 . Biological: pollen, fungi, bacteria. 5/31/2017 9RABIA AZIZ
- 10. Emissions of particulate matter can therefore be from natural sources or from human activities: Particulate matter emissions from human activities are closely dependent on dust removal equipment, processes and operating conditions. The main sources of emissions are: ploughing, construction sites, public works and civil engineering, quarrying, combustion of solid mineral fuels, liquid fuels and biomass. The order of importance of emissions from these different sources depends on the size distribution of the particles considered. Particulate matter emissions from natural sources are closely related to climate and natural conditions (wind erosion, forest fires, volcanic eruptions, pollen, wind-blown soil and sand, sea salt etc.) 5/31/2017 RABIA AZIZ 10
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- 13. Industrial Sources of Particulate Emissions Iron & Steel Mills, the blast furnaces, steel making furnaces. Petroleum Refineries, the catalyst regenerators, air-blown asphalt stills, and sludge burners. Portland cement industry Asphalt batching plants Production of sulfuric acid Production of phosphoric acid Soap and Synthetic detergent manufacturing Glass & glass fiber industry Instant coffee plants 5/31/2017 RABIA AZIZ 13
- 14. Types Of Particulate Matter The different types of particulate matter may be divided into three categories: primary particulate matter: directly released into the atmosphere by a large number of human and natural sources (see list above). secondary particulate matter: formed by physical and chemical reactions from other pollutants, called precursors. re-suspended particulate matter: after it has been deposited, particulate matter can then return into the air through wind action or road traffic disturbance in urban areas, 5/31/2017 14RABIA AZIZ
- 15. Important Terms Describing Atmospheric Particles Term Meaning Aerosol: Colloidal-sized atmospheric particle Condensation aerosol: Formed by condensation of vapors or reactions of gases Dispersion aerosol: Formed by grinding of solids, atomization of liquids, or dispersion of dusts Fog: Term denoting high level of water droplets Haze: Denotes decreased visibility due to the presence of particles Mists: Liquid particles Smoke: Particles formed by incomplete combustion of fuel 5/31/2017 15RABIA AZIZ
- 17. PARTICULATE MATTER AND HEALTH 5/31/2017 17RABIA AZIZ
- 19. Symptoms of exposure to particulate matter: People with heart conditions may experience: Chest pain Irregular heartbeat Shortness of breath Fatigue Heart attacks Coronary artery disease (CAD) is the most common heart problem related to long term exposure to PM2.5 5/31/2017 19RABIA AZIZ
- 20. People with lung conditions may experience: Coughing Shortness of breath Decreased ability to breathe deeply or vigorously Increased susceptibility to respiratory infections Aggravation of existing lung conditions like asthma and chronic bronchitis Healthy people may experience temporary symptoms like: Eye, nose, and throat irritation Coughing Chest tightness Shortness of breath 5/31/2017 20RABIA AZIZ
- 21. General Methods For Control Of Particulate Emissions Five Basic Types of Dust Collectors: Gravity and Momentum collectors Settling chambers, louvers, baffle chambers Centrifugal Collectors Cyclones Mechanical centrifugal collectors Fabric Filters Baghouses Fabric collectors 5/31/2017 RABIA AZIZ 21
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- 23. Electrostatic Precipitators Tubular Plate Wet Dry Wet Collectors Spray towers Impingement scrubbers Wet cyclones Peaked towers Mobile bed scrubbers 5/31/2017 RABIA AZIZ 23
- 24. Particulate Collection Mechanism Gravity Settling Centrifugal Impaction Inertial Impaction Direct Interception Diffusion Electrostatic Effects 5/31/2017 RABIA AZIZ 24
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