If the swimming pool pump is the heart of the swimming pool water treatment system and provides continuous power, then the swimming pool sand tank is the lung of the swimming pool water treatment system, filtering impurities and returning you clean! Based on the kiyea company's 25 years of experience, some experience in the selection and use of swimming pool sand tanks will be shared with everyone.
1. Selection of sand tanks for swimming pools. We often encounter customer consultations. What size sand tanks should I use for my swimming pool? Generally speaking, the size and number of sand tanks used in the swimming pool are determined by the swimming pool size and cycle time. The specific calculation method is as follows:
Pool water capacity V = length X width X average depth
Circulation flow Q=pool water capacity X1.05÷circulation period 4h
Note: The swimming pool cycle is 4 hours.
For example, if a swimming pool is 25m long, 16m wide, and an average depth of 1.4m, the water volume of the pool is 25mX16mX1.4m=560m³, and the filtration cycle is once every 4 hours, and the circulating flow rate is 560m³X1.05÷4h=147m³/h.
The circulating flow rate of the swimming pool is 147m³/h, then the medium-speed filtration (25m/h) is calculated. According to the actual needs, four sand tanks with a diameter of 1400 can be selected for filtration (unit: mm).
(AQUA side swimming pool filter sand tank ↑) Note: The filtration rate is the amount of water filtered per unit of filtration area in a unit of time. In order to standardize the filtration speed of the filter and facilitate the design and selection, when the filtration speed v≤10m/h, it is called low-speed filtration; when the filtration speed is 11-30m/h, it is called medium-speed filtration; the filtration speed is 31-50m/h When it is called high-speed filtration.
Practice has proved that: the filtering speed is within the range of 10-25m/h, and the filtering effect and the pressure loss of the filter are proportional to the filtering speed. If the filtration speed exceeds 25m/h, the filtration efficiency will decrease quickly, that is, as the filtration speed increases, the quality of the effluent after filtration will continue to deteriorate. Therefore, in order to ensure that the filtered water quality meets the requirements of sanitation, health and clarity, the filtration speed of public swimming pools should be ≤25m/h.
2. Sand cylinder head and multi-function valve. The Chinese translation or usage of the function of AQUA Exa cylinder head and six-position valve has always been one of the hottest questions. How to install the several interfaces on the sand tank head? There is a simple and easy-to-understand slogan: top in and bottom out side drainage, the meaning is very straightforward, the icon:
The function and operation method of the six positions of the filter multi-directional valve:
1. FILTER:
Press down the handle on the cylinder head controller and push it to (FILTER) for normal filtration, then start the swimming pool pump, and filter normally.
2. BACKWASH:
The sand in the sand tank constitutes thousands of water passages, and various impurities are filtered and left in the filter. As the impurities increase, the water passages gradually decrease. This is why the pressure can reach more than 30 kilopascals (kpa). Under this pressure, the sand tank cannot play any filtering function. It must be cleaned as follows: turn off the water pump, open the multi-directional valve to the "backwash" position, and open the bottom discharge and loop valves. Start the water pump for about 3 minutes. When the operation is completed, the agglomerated impurities will be removed.
3. RECIRCULATE:
In this position, multiple valves control the water flow from the pool pump directly to the pool water without passing the water flow through the filter.
4. WASTE:
If the pool water needs to be drained, a filter water pump can be used. To this end, the multi-valve must be placed in the WAST drain position. When the motor is running, the drain valve must be fully opened so that the water pump can fully absorb water.
5. RINSE rinse
After the filter is backwashed by BACKWASH, if the multiple valves are returned to the normal filtering position of the FILTER, the water flow will be turbid for a few seconds. To prevent muddy water from entering the pool, the multiple valves must be placed in RINSE for rinsing s position.
6. CLOSED
This position is used to close the water flow from the filter to the swimming pool water pump and is used when opening the hair collector of the water pump.
Precautions for the use of sand tanks in swimming pools:
1. When turning the handle of the cylinder head control valve, the control valve handle must be pressed down to prevent damage to the seal of the control valve!
2. When turning the control valve, the water pump must be turned off!
3. Avoid letting the sand filter tank work pressure higher than 35 kilopascals (kpa)!
4. Clean the hair collector regularly!
5. Prevent water leakage and confirm that all pipe connections are firm and reliable!
3. How often does it take to backwash? There is no fixed formula for the backwash cycle of the filter. Just like eating, you can eat as long as you are hungry. Moreover, the filter has a wide range of uses, used in different industries, the amount of impurities and other factors are different, and the cycle of backwashing is also different. The following analyzes several factors that affect the backwash cycle:
1. Different application places. For example, some customers use the filter sand tank to filter impurities in mountain spring water. In this case, the mountain spring water is generally clear, so it is possible to backwash once every ten days and a half. However, some customers are used to filter impurities in urban sewage. In this case, it may be backwashed once a day.
2. The filter selection is different. The flow rate of the sand filter tank will vary with factors such as the flow rate of the water pump, the thickness of the sand layer, the size of the sand material, and the filter area. In the case of the same suspended solids content and the same flow rate, theoretically speaking, the larger the sand tank, the larger the filter area, and the smaller the resistance to the water flow. The higher the filtering accuracy. The cycle of backwash is also shorter.
3. The customer's subjective judgment is different. Because some customers have subjective differences in the judgment of the sewage after backwashing. Therefore, the backwash cycle is also different according to his judgment.
Solution: A cycle can be determined according to the turbidity of the previous backwash sewage and the reading of the pressure gauge. For example, during normal filtration, the count of the pressure gauge is 0.1MPa. When the reading of the pressure gauge reaches 0.2MPa, we backwash once and find that the discharged sewage is not so dirty. Then we understand that the next backwash time can be extended. Repeated several times, and each time we recorded this time interval. An optimal backwash cycle will be obtained.
4. When should the pool filter be replaced with sand? It is best to replace the quartz sand in the sand tank of the swimming pool once every 1-2 years for the following reasons:
1. When backwashing, the filter layer will expand up by 1.2 to 1.3 times the volume. The upward water flow will drive the filter layer to flow up and down, causing the filter material particles to collide with each other. Because the material is the same, the hardness is the same. Therefore, the filter material has some parts. It will break into fine particles and be lost with the backwash water;
2. Due to insufficient purity of some quartz sand, welding will occur when the acid-base changes;
3. After long-term use, the inside of the filter layer will be partially surrounded by colloid due to the uneven distribution of water flow, and lose its effect;
Therefore, the longer the time, the worse the filtering effect of the filter. Since backwashing will consume and take away some sand, we need to replace the sand in the filter tank within the specified time limit.
For more questions about pool filter selection, use and maintenance, please continue to pay attention to kiyea company, or call us directly at 020-36683503.