Clean water treatment by gravity fast filter tank

Flowchart of clean water treatment technology by gravity fast filter tank

Figure 1: Flowchart of clean water treatment technology by gravity fast filtration tank

Technology Description:

–     The source water will be treated by a settling work to settle large particles, then filtered in by a gravity fast filter tank system to remove small particles, and finally added. Add disinfectants to disinfect bacteria.

–     Open gravity quick filter tank is built of reinforced concrete, The filter tank has a water distribution system and washing filter with filter floor. The filter tank can have 02 compartments or 01 filter compartment. The height of the water layer on the filter sand is greater than or equal to 1.2 m; Filtration speed from 6-10 m/h.

Figure 2: An example of a fast gravity tank.

1-Raw water pipes; 2-Hole drilling system distributes washing water and collects filtered water; 3-Condition of filtered water to the clean water tank; 4- Drain pipe for washing and filtering water; 5-Trough distributing raw water and collecting wash water; 6-Pipe for clean water to wash the filter tank; 7-Drainage ditch for washing water; 8 ditches to concentrate water for washing and filtering; 9-Wind ducting and distribution system.


–     Simple handling system.

–     Suitable for treatment systems with a large capacity of thousands of m3 of water per day.

–     Low investment cost.


–     The plan to use the construction treatment tank; assembled equipment, so the stability when operating is not high, it takes a lot of labor to operate,

–     As a traditional water treatment method, it takes up a lot of space,

–     Not suitable for systems with small capacity,

–      Using an open filter tank, there is a phenomenon of algae, moss, and insect corpses in the filter tank, affecting the quality of water treatment,

Scope of application:

–     This water treatment method is suitable for factories with a large capacity of thousands of m3/day with low water quality requirements after treatment.