Download to read offline
Uploaded byGARRE RAVI KUMAR
Monitoring of Particulate matter
The document discusses various methods for monitoring and collecting particulate matter from polluted air, including filtration, sedimentation, impingement, impaction, electrostatic precipitation, and thermal precipitation. Each method employs different techniques to capture particles of varying sizes, from fibrous filters for fine particles to gravitational sedimentation for larger particulates. The document also details the operational principles of devices used in these processes, such as impactors and electrostatic precipitators.
In this document
Powered by AI
Overview of monitoring techniques for SPM including filtration, sedimentation, and several collection methods.
Filtration removes particulate matter from air using fibrous filters, effectively capturing fine particles below 0.1 microns.
Sedimentation allows coarse particulates over 10 microns to settle due to gravity, commonly using a dust fall jar.
Impingement traps particulates via collision with obstacles in air streams, utilizing dry or wet impinger methods.
Impactors force air through small holes to separate particles, conveying progressively finer particles through stages.
Electrostatic precipitators efficiently collect dust and particulate matter ranging from 0.1 to 10 microns from exhaust gases.
Thermal precipitators use temperature gradients to deposit particles in air streams for morphological analysis.
Concludes the presentation.
More Related Content
Similar to Monitoring of Particulate matter
More from GARRE RAVI KUMAR
Monitoring of Particulate matter
- 1. Monitoring of SPM RaviKumar GARRE
- 2. Contents covered • Filtration •Sedimentation • Impingement • Impaction • Electrostatic precipitation • Thermal precipitation
- 3. Filtration • Filtration ofpolluted air is a convenient method to remove the particulate matter in it. • The filters used for this purpose are generally made up of fibrous substances. • They have the ability to remove larger particles to fine particles with high efficiency. • The instrument used to collect particulate matter of size less than 0.1 micron in size
- 4. Sedimentation • The coarsesettleable particulate matter of size greater than 10 microns in diameter can settle out under the influence of gravitational force. • The dust fall jar/ container is preferred device for collection of bigger particulates.
- 5. Impingement • In thismethod the particulates in the high velocity air stream is made to collide with an obstacle in an impinger so that the air stream is deflected after striking the obstacle. Dry impinger: • The particulates in the high velocity air stream strike the obstacle which is a solid with adhesive surface. Wet impinger: • In this type, the particulates in the high velocity air stream strike the obstacle placed in a liquid so that the particulates are trapped in the liquid medium.
- 6. Impaction • Impactors arethe devices in which air is forced to pass through small holes and strike against another solid surface plate with smaller holes. • A cascade impactor consists of several such plates with progressive decrease in the size of holes. • The air stream passing through each plate impinges at an increased velocity. • The coarse particulate matter is separated at the first stage and the finer particles are separated at a later stage. • The particulate matter deposited at each stage is collected and the total weight and chemical composition is determined.
- 7. Electrostatic precipitation • Electrostaticprecipitators (ESPs), also known as electrostatic air cleaners. • These are special devices used in general air cleaning system in industrial operations which produce exhaust gases containing dust, fly ash, fumes and mist. • They are so called because electrostatic forces separate the dust particles from the exhaust gases. • Such devices are efficient enough to collect particles in size range of 0.1 microns to 10 microns.
- 8. Thermal precipitation • Thisinvolves the use of thermal gradient to collect the particulate matter. • The device thermal precipitator consists of two adjacent surfaces with a strong temperature gradient. • The air stream is made to flow in between the two surfaces at slow rate of 10 to 25 ml/minute. • The particulate matter in air gets deposited on the colder region of the plates. • The accumulated particulates in the collection area is sent for further microscopic analysis for the number of particles and morphological characteristics.
- 9.