The quartz sand filter mainly uses quartz sand as the filter medium. Under pressure, the water with high turbidity is filtered through the granular or non-granular quartz sand of the corresponding thickness, and the suspended solids, organic matter and glue in the water are well intercepted and removed. It is a kind of filter equipment that can reduce the turbidity of water. However, some customers found that the water output of the quartz sand filter is not very good during use. What is the reason for this phenomenon? The specific influencing factors are as follows:
1. Uniformity of water flow
Whether it is running or backwashing, the water flow distribution of each section is required to be uniform. To make the water flow evenly, the main thing is that the drainage system should be prominent. As long as the water flow is uniform, the filtering effect can be outstanding.
2. Filtration speed
The filtration rate of the quartz sand filter should not be too slow. Because the filtration rate is too slow, the amount of treated water per unit filtration area is small. In order to achieve a fixed water output, to increase the filtration area, it is necessary to increase investment. However, if the filtration speed is too fast, it will not only increase the loss of water head, but also shorten the filtration cycle and reduce the quality and quantity of the effluent. The filtration rate is generally selected from 10 to 12m/h.
3. Backwash
Backwashing is used to remove the sludge in the filter layer to restore the filtration capacity of the filter material. In order to wash the sludge clean, there must be a corresponding backwash speed and time. This is related to the size and relative density of the filter material, expansion rate and water temperature. During backwashing, the expansion rate of the filter layer is 25%~50%, and the backwashing time is 5~6min. As long as the backwashing effect is good, the sand filter can work well.
Daily management of quartz sand filter:
1. After the system has been shut down for a long time, when it is reopened, the filter material should be washed for about 5-30 minutes until the water is clear and stopped.
2. When the system is running for the first time or after a long-term shutdown, the equipment should be exhausted.
3. For large filters, it can be wiped with air to enhance the backwashing effect. Generally, compressed air is introduced, and then the corresponding air-water backwashing is performed.
4. When the equipment is backwashed, the backwashing strength should be well controlled, and the quartz sand should be prevented from leaking out of the system.
