Automatic Valveless Gravity Filters are atmospheric sand filters, often employed as side stream filters in cooling towers circuits for their characteristics:
No rotating equipment, no PLC, no ON/OFF valves are associated to the system
The capacity to handle high flowrate of water
The simple and robust design
The little maintenance required
The filter includes a filtration chamber, a backwash water hold-up reservoir overflowing to the treated water header and backwash siphon.
When the pressure drop through one filter reaches the break-through value the siphon is primed. Water contained in the internal reservoir backflows to the waste water channel, backwashing the filtering sand layer. Then the filter returns to normal service.
Unidro design include different options for each project optimization:
Multi-filter systems with distribution tower for flexible management of large flowrate with transportable size equipment
Double bed filters for minimum footprint
Site assembly of shop preformed sheets for filters larger than transportation limits
Concrete fabrication instead of steel shells for cost optimization
Multiple chamber combined filters for large capacity systems