Envites - Continuous open
PRODUCTS > Sand filters > Continuous open

Fields of use
Filtration process using the sand filter
Offered models


  • Continuous operation
  • Attendance-free operation
  • Performance maintained even at uneven loading
  • High operating reliability
  • Minimum requirements for maintenance

For more information about the benefits click here (link to sand filtration)

Main fields of use of the continuous sand filters:

Designed for pre-treatment and secondary treatment of water during filtration:

  • Surface water
  • Industrial water
  • River water
  • Cooling water
  • Coagulating filtration
  • Secondary water treatment

For more information about the filed of use click here (link to sand filtration)

Description of the continuous filters:

ENVITES produces continuous counterflow sand filter in seven size classes with diameters of 600 - 3000 mm (filtration surface area from 0.28 m2 to 7,05 m2). Each of these types is produced in three height designs: low "L", medium "M" and high "H". The tank jacket is made of stainless steel, polypropylene or fibreglass. The built-in pat is made of stainless steel or polypropylene.

Basic parts:

1. Tank
2. Washing column
3. Support
4. Air pump
5. Sand bed
6. Inlet
7. Filtrate outlet
8. Washing water outlet
9. Distributing channel - distributor





Filtration process in a continuous filter

The liquid is cleaned when passing through a sand layer. The liquid is fed through the inlet in the central part of the tank into the distributor, which evenly distributes the liquid over the filtration layer. By passing the liquid through the filtration layer, the suspended solids get separated. The filtered liquid rises to the top of the tank and overflows out of the system. Polluted sand is extracted from the bottom of the tank and is lifted by the central pipe to the washing room in the upper part of the tank. The sand enters a vertical counterflow column and it is washed by a part of the filtered liquid stream. It is cleaned by means of the different settling speeds of the suspended solids. Polluted washing water is discharged by the overflow over the column. Sand circulation ensures continuous regeneration of the filtration layer without a necessity to interrupt the filtration process.

Offered models:

filtration area (m2)
Ø (m)
high (m)

0,28 - 7,05
0,6 - 3,0
2,38 - 5,55