Quartz sand filter is to use quartz sand as the filtering medium, filtering high turbidity water through a certain thickness of granular or non-granular quartz sand under a certain pressure to retain and remove suspended matter and organic matter.

Filtration speed: The filtration speed of quartz sand filter media should not be too slow. As the filtration speed is too slow, the water volume per unit filtration area will become smaller. In order to achieve a certain amount of water, the filtration area must be increased, which also requires increased investment. But too fast filtration speed will not only increase the head loss, but also shorten the filtration cycle and reduce the quality of the water. Therefore, the filtration speed of quartz sand filter tank is generally 10-12m/h.

Backwashing: Backwashing is used to remove the sludge from the filter layer of the quartz sand filter tank, thus restoring the filtering capacity of the filter media. In order to clean the sludge, there must be a certain backwashing speed and time. This is related to the size, relative density, swelling rate and water temperature of the filter media. The backwashing strength of quartz sand is 15L/(M2-s), the swelling rate of the filter layer during backwashing is 25%~50%, and the backwashing time is 5~6min. only if the backwashing effect is good, the sand filtration can run well.

Uniformity of water flow: Both operation and backwashing require uniform distribution of water flow in each section. To make the water flow evenly, the drainage system should be good. Only the uniformity of water flow can make the filtration effect good.

When loading quartz sand filler into the filtration device, the following points should be noted:

(1) The number of people going down the pool when laying should be as small as possible to avoid trampling on the sand layer that has been laid. When feeding into the pool, should be carried out in the state of full water, to avoid damage to the paved filter layer due to the impact of the material sand.

(2) each layer of the filter layer according to the ratio of the number of cast enough, should be drained. Scrape and correct the height of the filter layer, and then backwash until the surface of the filter layer is clean. Later, then from the bottom up into the water, according to the above method to lay the small particle size filter layer.

(3) pavement filter layer to be strictly graded, to be layered clearly. In each layer of filter sand into the pool, are to be flushed, flushing should gradually reduce the intensity of flushing before stopping, in order to complete the effective hydraulic stratification, so that the light impurities concentrated in the surface of the filter layer, in order to scrape off.

4）After each rinse, can scrape the surface layer 0.5-1.0cm. scraping should master the proportion: that is, to scrape the impurities, but also to prevent scraping too much and affect the gradation.

5）After all the filter material is loaded, the water is fed from the bottom upwards, so that the water level is discharged to the top of the drainage tank, and the surface of the filter layer is clean.

Related Products

Shallow sand filter

Self-cleaning filter