1. General introduction:
"Steel Gravity Valveless Filter Tank" is manufactured by the manufacturer, with non-toxic paint for anti-corrosion, and the filtered water volume is 20M 3 /h to 175M 3 /h , all of which are transported to the site as a whole; the filtered water volume is 200M 3 /h to 500M 3 /h and 300M 3 /h to 750M 3 /h are prefabricated and assembled into several parts by the manufacturer in the factory. After transporting to the site , the manufacturer's personnel continue to weld them . After mutual anti-corrosion , the small size of the filter tank series uses a square, flat top cover, and the large size uses a round, vaulted top cover, which has good sanitary protection conditions and can be installed in the open air, compared with reinforced concrete filter tanks., Small self-weight, tar sand flexible foundation can be used.
2. Process introduction:
This filter tank series adopts a small resistance drainage system, positive and gravity filtration, and backwashes under the action of the siphon head with the amount of water in its own clean water area. Therefore, it is not necessary to set up a backwashing pump or a backwashing water tower like the High-speed filter, Medium-speed filter, mechanical filter and ordinary fast filter tank. In the filter tank, a large number of flushing and clean water pipes are used, and they are arranged at the centroid axes of the respective area figures, so the backwashing water is evenly distributed. The filtered water is collected by a polygonal water collecting tank in the clear water area. Therefore, after the filter tank is in place, it has a strong adaptability to the level of the weir roof of the water collecting tank, so that the water can be collected evenly.
In the larger specification products of this series of filter tanks, compared with the reinforced concrete gravity type valveless filter tank of the national standard diagram, each group of three-seat series is added (that is, when a filter tank is backwashed, the same group of three The amount of backwash water supplied by the filter tank), the maximum control value of the final head loss is also increased by 1.50 meters and 1.90 meters from the national standard map of 1.70 meters , providing a convenient product for the elevation layout of the water purification plant design. 3. Description of process characteristics:
When the filter tank is running, filtration -- putting into backwashing - terminating backwashing - resuming the next cycle of filtration are all carried out automatically. This kind of automatic, belongs to hydraulic automatic, and does not require personnel to take care of it. 

Description :
Steel gravity valveless filter series products are widely used in surface water purification, iron and manganese removal from groundwater, bypass flow of circulating water, removal of suspended impurities from production wastewater, and subsequent filtration of organic sewage after biochemical treatment and secondary sedimentation tank treatment. As well as the filtration of indoor swimming pool water, it is an ideal water treatment equipment.
At present, the Valveless filter produced by our factory has two series: one is the square CBL -Ⅱ type filter, the filtered water volume is 20m3 /h to 175m3 /h ; the other type is the circular DLB- Ⅱ, DLB- Type III, the amount of filtered water is 20m3 /h to 80m3 /h , 200m3 /h to 750m3 /h . Among them, those with a filtered water volume of 20m3 /h and 175m3 /h are transported to the site as a whole, and those with a filtered water volume of 200m3 /h to 750m3 /h are prefabricated by our three parts, transported to the site to assemble, and then anti-corrosion. Delivered to the construction unit, it can be debugged and run after filling the filter material.

4. Design parameters
1. Average filtration speed: 10 m / h2 . Average backwash intensity:  15 liters / m2 . Seconds3 . Backwash duration: 5 minutes4  . Final head loss: 1.50 m , 1.70 m, 1.90m ( 3rd gear optional) 5. Backwash expansion height: 700 × 40% plus 100mm safety height 6. Filter material layer height: 700mm , supporting layer thickness 270mm Water purification) 8. Turbidity of effluent: no more than 3 degrees (for surface water purification)
Specifications and parameters: The water treatment capacity of this equipment is 20m³ /h-900m³ /h
20M³ /hto 175M³ /h

200M 3 /h to 750M 3 /h