Working principle of swimming pool sand filter
The sand filter of swimming pool is the main part of the circulation system, which is used to filter the water of swimming pool and purify the water quality.
Then what is the working principle of the sand filters?
Why the filters need to add the silicon sand inside?
As we known, water can infiltrate into the surface to become clear groundwater; when we do experiments, we can pour the turbid water into the deep sediment to filter, and then we can filter out the clean water. So, the sand tank is to use the principle of deep filtration to filter the water quality. When the pool water passes through the sand tank, the impurities in the water will be intercepted by the sand, and the clear water will flow back to the pool through the pipe.
The stone filled in the sand filter is quartz sand, which is the special filter sand to remove the tiny dirt in the pool water. Sand filtering is not required to fill the whole sand filter. It can be filled to about 2 / 3 of the position. When the control knob is turned to the "FILTER" position, the pool water containing suspended dirt particles is pumped into the filter pipeline, and then led to the water outlet of the filter by the control switch. The water in the pool is filtered by the sand tank, and the tiny dirt is intercepted and filtered by the sand bed. The filtered clear water will be returned to the swimming pool through the pipe by the control switch at the bottom of the filter. The whole program is continuous and automatic, and a complete circulation system is composed of the pool sand filter and the pipeline.
The circulating system is often used. After a long time, the surface of the sand filter will be covered with a large number of filtered impurities. The more these impurities accumulate, the weaker the filtration effect will be, and the weaker the filtration effect of the whole circulation system will be. Therefore, after a certain period of use, the filter needs to be cleaned, which is commonly referred to as backwash. Backwashing is an important part of sand tank maintenance in swimming pool. First, turn the control switch to the "BACKWASH" position to make the water flow in the opposite direction. The water flows upward from the bottom of the sand tank and flows up through the sand layer. The accumulated dirt and residue intercepted before will be washed away and sent out from the drain outlet to clean the inside of the sand tank. After backwashing, turn the control switch to "RINSE" position, turn on the water pump for 0.5 to 1 minute, then turn it off, and then turn it to "FILTER" position to restart normal filtration.
