Untreated water enters via the inlet which is located at the top of the vessel and is passed through the patented DVF vortex generator. This pipe has a dual outlet configuration inside the vessel which generates a double vortex. This allows for the solids to be suspended above the filter bed. This leaves the water being cleaned free to pass through the specially constructed media bed with less resistance whilst giving the filter bed longer life before backwashing is needed. The filter bed is constructed of 4 different grades of Active Glass media of which the coarse layer is used at the bottom, followed by 2 additional layers of support media and the special blend top layer. The cleaning process is achieved by backwashing the media.
Backwashing the filter bed is achieved by either a set time or, if backwashing is needed sooner, a pressure differential gauge which senses the Delta P when it reaches the pre-set value. Once this has been triggered either by time or pressure differential, then the self-cleaning process begins. The inlet valve shuts followed by the process water out valve.
The backwash valve then opens followed by the drain valve. This forces the water being used for backwashing up through the nozzles at the bottom of the vessel, through the filter bed which lifts the solids from the top layer of the media.
Once lifted off the bed it is discharged through the drain which is located at the top of the vessel. When the backwash is finished at a pre-determined time, the valves shut in reverse and filter process is resumed.
An AC controller allows for the backwash timings to be altered to suit the specific site requirements. It also allows for pumps to be added to the system to aid with process and/or backwash flow. There is also a manual backwash facility which will work in conjunction with the set time and differential pressure settings for the filters.
The self-cleaning cycle is initiated as a result of any of the following:
Receiving a signal from the pressure differential gauge
Time interval parameter set at the controller
Manual start
Remote access
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