Media (Sand) Filters
Media (Sand) Filters
The HEI low profile gravity flow sand filter continuously filters, by gravity, liquid suspensions producing excellent filtrate while simultaneously and continuously cleaning the filtration bed.
HEI’s low profile filter backwashing is a unique process. A slip stream of the most contaminated media, is taken from the bottom, cleaned and automatically redeposited on the top of the filter bed. The filter bed media slowly moves downward as the filtered water moves upward through the bed.
Since the HEI gravity flow sand filter continuously cleans a small portion of the media bed, the dirty backwash water, comprising approximately 5% of the total flow, may be continuously returned to the primary clarification device without stopping or surging the system.
A conventional pressure sand filter backflushes on a batch basis producing large intermittent flows of wastewater. In addition, the large volume of backflush water must be accumulated and held in reserve until it can slowly be treated. The HEI low profile continuous backflush sand filter eliminates the requirement of tanks and pumps to store, pump and process the backflush water.
HEI gravity flow sand filter is a low profile designed unit enabling direct flow of the influent from standard clarifiers. A conventional clarifier does not need to be raised to provide the required water column for HEIs sand filter operation. And, as well, pumping or lift station from standard clarifiers are not required with HEI’s low profile media filter.
Advantages of HEI’s Low Profile Media Filter
Low Profile Gravity Sand Filter VS. Pressure Sand Filter
Filtration Equipment Required:
- One (1) HEI Gravity Sand Filter
Filtration Equipment Required:
- Influent Surge Tank
- Influent Pressurization Pump
- High Pressure Vessel
- Pressure Sand Filter
- Backflush Pump
- Backflush Reservoir
- Waste Backflush Surge Reservoir
- Waste Backflush Return Pump
- Pressure Sand Filter Controls
- Pressure Switch
- Pressure Guage
- Air Vent
- Compressed Air Media Scrubber
- Pressure Relief Valve
- Automatic Valves With Operators
- Valve Positioners
- Valve Position Indicators
- Central Control System
- Motor Starters
- Disconnect
- PLC
- Switches