Gravity Filter

Usage functions

The gravity filters produced by DEPURMAC come as individual filters or as a “monoblock” filtration station to limit costly masonry work. The monoblock feature allows for easy installation and quick commissioning compared to conventional systems. This system is generally used in tertiary filtration treatments of primary water and discharge for residential and industrial use, where the goal is to obtain a very clear effluent with reduced presence of organic substances and suspended solids for reuse.



Construction Features

The plant is constructed based on the flow to be treated.

The filtration station consists of an above-ground unit that includes the filters (usually activated carbon) and the associated filtration and backwashing circuits. The station is complemented by a raw water collection and re-pumping basin, a clean water storage and pump tank for filter washing, and a saturator for generating an air-water mixture used in backwashing.

The filtration and backwashing circuits are constructed using flanged pipes and fittings to channel the water. The two circuits are connected to the supply pipe of the raw water feed pump and the clean water pipe and are equipped with shut-off valves that determine the following operating modes:

a) Sequential filtration

b) Backwashing.

The filter doesn’t necessarily require a collection basin; it can be installed downstream of other treatment systems (e.g., chemical-physical, biological, etc.). The treated water can be discharged either by gravity or through pumping.


  • High efficiency in removing suspended solids.
  • Low operating costs.
  • No need for backwash pumps.
  • No installed control system.
  • No need for a dedicated tank for backwash water.


Available in painted carbon steel or hot-dip galvanized carbon steel / AISI 304 stainless steel according to customer specifications.


The filtration plant essentially consists of:

  • A cylindrical tank
  • Fittings
  • An automatic backwashing system
  • A raw water feed and recirculation tank
  • Filter nozzles
  • A filter bed
  • Pneumatic valves
  • Water/air flowmeters
  • Corresponding safety valves.

Purchase request

You will be contacted by one of our technicians to study the best solution together.
Purchase request