Overview: Introduction to Filtration
Filtration is a process of separating particles from a suspension in water or wastewater treatment. Filtration is a type of mechanical separation that is primarily based on physical principles. Filtration, filtering, and draining are all phrases that are used interchangeably.
What is the Principle behind filtration in WWTP?
Filtrate is the liquid that has been filtered. The filter cake/residue stays in the filter. The pressure decrease that occurs during filtering, also known as filter resistance, is referred to as loss of pressure. Solids create an increasingly thick layer on the filter media as the filter is filtered off.
Working process of filtration
The combination to be separated goes through a filter made up of filter materials such as filter sand and filter gravel in water or wastewater treatment. All of the particles in the mixture to be separated are resistant to the filter material. The deposition of the trapped chemicals gradually reduces the pores of the filter material.
Backwashing of filter cake
A full separation of the particles would be achieved after building up a sufficiently thick filter cake, but the flow resistance of the filter would grow dramatically, necessitating an intervention in technical applications much sooner. It's also conceivable that the particles that need to be eliminated won't be held any longer. In this situation, the term "filter break" or "crash" is used.Backwashing the filter cake or residues on a regular basis is required to avoid both. Backwashing involves reversing the filtering process and rinsing the filter's contaminants.
Principles of filtration and cleaning in wastewater treatment process
1: The dirty raw water is supplied into the filter, where the filth particles settle on the filter sand, gradually increasing pressure loss (they "clog" the filter"). The pressure drop is routinely measured in technological setups. Backwashing is started when a (specified) value is achieved beyond which the filter can no longer perform a useful function.
2: Fresh water and/or air pulses are carried out from the bottom of the filter while backwashing. Individual grains 'float apart' (technically = it 'fluidizes,' 'the process called fluidization') as a result of pressure that builds up from the bottom up. It's also known as a filter bed expansion.
3: The lighter filter carbon in the multilayer filter is situated above the lighter filter carbon in the multilayer filter. At the same flow rate, the filter carbon filters the coarsest particles and has a substantially higher expansion (therefore coarser particles are better to rinse).
Two things happen in the filter bed as a result of the expansion process!
4: On the one hand, the pore volume rises in the filter bed between the "floating" particles. As a result, dirt particles bonded in the interstices float freely with the flow. Dirt particles are released with wastewater and externally deposited or treated using various removal equipment.
5: The grains, on the other hand, categories during the sinking period. The grains are sorted by weight after a series of flushing operations (big lie down - small lie above).Under a layer of filter coal, different sized filter sand and gravel are put in a multilayer filter.
Technical assistance and guidance
Netsol Water collaborates with a wide range of international organizations to tackle complicated problems by strategically integrating modern treatment technology with practical solutions. We can also provide a good framework of WWT plant, among other services.