Technical data: Gravity-type valveless filter

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This post was last edited by hesonchang214 on 2009-7-11 20:09. Working principle: Tap water enters the filter through the distribution tank and is filtered from top to bottom. As the filter layer continuously traps the suspended solids in the incoming water, its head loss gradually increases, causing a siphonic rise and an increase in the water level in the pipe. When the water level rises and enters the ejector within the siphon assist pipe, the hydraulic force carries away the air from within the siphon tube, creating a negative pressure. When the negative pressure reaches the designed value, siphoning occurs, and at this point the water in the tank is backwashed from bottom to top to be \"regenerated\". Due to the continuous backwashing of the filter layer, when the water level in the tank drops to the specified value, the siphon effect is disrupted, the backwashing comes to an end, and the filtration unit resumes its operation. Features: 1. This device is one of the first of its kind in China to operate automatically without the use of valves or control instruments; it makes use of the siphon principle to achieve automatic operation. Compared to other filtering devices, it offers advantages such as no need for manual operation, low energy consumption, reduced operating costs, high safety and reliability, and easy maintenance. 　　2. The equipment is assembled from a water supply tank, filter, U-shaped water inlet pipe, drainage tank, etc., featuring a compact structure. Users only need to prepare the appropriate foundation for the equipment and connect the inlet and outlet pipes before it can be put into operation. 　　3. The equipment is made of carbon steel (or as per the customer’s requirements), features excellent corrosion resistance, high manufacturing precision, and is easy to install. Uses: 1. Used for the secondary filtration treatment of circulating cooling water in industries such as petroleum, chemicals, metallurgy, power generation, oil refining, light industry, and textiles ； 2. Used for surface water purification, and for removing iron and manganese from groundwater ； 3. Used for filtration in urban and rural water treatment plants ； 4. Pretreatment for softening and desalination ； 5. Used for the purification of swimming pools and fountain landscapes ； 6. Used for removing suspended solids from wastewater; subsequent filtration after biochemical treatment and secondary sedimentation of organic wastewater ； Scope of application: 1. When used for filtration in water treatment plants, the suspended solids in the inlet water should be less than 15 mg/l, while those in the outlet water should be less than 3 mg/l ； 2. When used for the side filtration treatment of circulating cooling water, the suspended solids in the inlet water are generally between 15 and 30 mg/l, while those in the outlet water are usually less than 5 mg/l ； 3. When using \"chemical coagulant treatment,\" the suspended solids in the influent range from 50 to 100 mg/l, while those in the effluent are generally less than 5 mg/l ； Schematic diagram of the equipment: http://www.lssg.com.cn/images/jsjs/zlswfglqjt.gif
Table of installation dimensions:
Model specifications: DLB20406080100120150200
Water production capacity (tons/hour): 20, 40, 60, 80, 100, 120, 150, 200
Overall dimensions:
Length (L): 3900, 4700, 5600, 6200, 7200, 7600, 8000, 9400
Width (B): 1800, 2200, 2600, 3000, 3600, 3600, 3800, 4400
Height of inlet tank weir H: 56, 61, 106, 63, 65, 80, 67, 50, 67, 50
Height of outlet weir H4/H5 – Final head loss (three options available: 1.5m, 1.7m, 1.9m)
Pipe dimensions:
Inlet pipe diameter: DN2100, 150, 200, 200, 250, 250, 300
Pipe elevation H2: 4710, 4810, 4810, 4810, 4810, 4810, 4810
Outlet pipe diameter: DN1100, 150, 200, 200, 250, 250, 300
Pipe elevation H1: 2000, 2000, 2000, 2000, 4000, 4500, 500
Drain pipe diameter: DN3300, 300, 400, 400, 500, 500, 600
Pipe elevation H3: 3270, 2700, 3000, 3000, 3600, 3600, 460
Plan dimensions of pipe openings:
Φ11400, 1800, 2240, 2460, 2990, 3210, 3430, 3640
Φ2900, 1000, 1000, 1200, 1200, 1400
C1134, 1350, 1540, 1636, 2000, 2100, 2200, 2445
E655, 780, 890, 945, 1155, 1213, 1270, 1412
F755, 950, 1125, 1225, 8288, 9910, 2712, 275
G970, 1200, 1450, 1580, 1880, 1990, 2110, 2280
Weight:
Net weight of equipment (tons): 6.6, 19.6, 11.88, 13.43, 20.8, 22.9, 25.6, 30.8
Total loaded weight (tons): 203, 246, 587, 896, 1081, 58
Note: The elevations of the pipes listed in the table are calculated based on a reference level of 0.000 at the foundation surface. Equipment foundation: http://www.lssg.com.cn/images/jsjs/zlswfglqzct.gif
Model dimensions: LBHΦacDDLB-2039001800100013009001134816, DLB-404700220010001700110013501000, DLB-605600260010002100130015401264, DLB-806200300010002300150016361464, DLB-1007200360010002700180020001600, DLB-1207600360010002900180021001700, DLB-1508000380010003300190022001800, DLB-2009400400010003600220025002200

Selection guidelines:
1. All elevations listed in the table are calculated with the foundation level set at ±0.00. 　　2. When a valveless filter is used for the side filtration of circulating cooling water, the amount of water to be filtered can be calculated using the following formula: 　　　　Q＝W×N/24 　　　　Q – Amount of water filtered per hour (m3/h) ； 　　　　Volume of the W-cycle cooling water system, including the bottom tank volume and pipeline system volume ； 　　　　N: The number of filtration cycles, usually 2 to 4 times; choose the higher value for water of poor quality. When system volume W is insufficient, it can also be estimated at 2–5% of the circulating cooling water volume (volume per cycle). 　　3. The forced flushing pipe indicated in the plan (DN25) can be connected to a water supply pipe or another water supply pipeline with a pressure greater than 0.25 Mpa. When the water supply pipe is laid underground, a valve (DN25) should be installed about 0.5 m above the ground surface at the connection point, for use during testing. 　　4. From the outlet of the valveless filter to the next structure, the height difference corresponding to the highest designed water level should take into full account the unobstructed flow of water from the filter; it should generally be H4 minus 2 meters, minus the pressure loss in the connection pipes. The water pressure at the inlet of this filter should be greater than 8 m. 　　5. The drainage pipes in the table are connected above ±0.00; as per the user’s requirements, they can also be connected below ±0.00: that is, the elevation of the DLB-100, 120, 150, and 200 models of drainage pipes can be changed to -0.45m. Skip the two elbows and connect directly to the inspection well; users should specify this requirement in the contract when placing the order. 　　6. To meet the requirements of large-scale circulating cooling systems for side filtration, our factory has designed a modular gravity-type valveless filtration unit. The capacities are 300 m3/h, 360 m3/h, 400 m3/h, 540 m3/h, 600 m3/h, 720 m3/h, 800 m3/h, and 1200 m3/h. Each specification comes with two layout options. Users can request relevant information from our factory according to their usage requirements. Our factory will provide detailed drawings of various layout options to help users accelerate construction progress and save space. 　　7. If users need to monitor the operating condition of the filter from a distance, please specify this when making the selection. Amount of filter media:
Model | Quartz sand particle size | Gravel layer particle size
0.5–1.0 mm | 2–4 mm | 4–8 mm | 8–16 mm
DLB-20 | 2.7 | 0.24 | 0.24 | 0.35
DLB-40 | 4.7 | 0.42 | 0.42 | 0.60
DLB-60 | 7.3 | 0.63 | 0.63 | 0.95
DLB-80 | 9.0 | 0.80 | 0.80 | 1.15
DLB-100 | 12.4 | 1.10 | 1.10 | 1.60
DLB-120 | 15.0 | 1.30 | 1.30 | 1.80
DLB-150 | 17.0 | 1.50 | 1.50 | 2.10
DLB-200 | 24.5 | 2.15 | 2.15 | 3.10

Note: The figures in the table represent the calculated weights; when placing an order, an additional 5–10% should be added to account for consumption losses.
Technical requirements for filter media: The filter media must comply with the standards specified in GJ24.1-88 issued by the Ministry of Construction. 　　1. The sum of the crushing rate and wear rate of quartz sand filter media should not exceed 1.5%, and its density should not be less than 2.55 g/cm3 ； 　　2. The quartz sand filter media should be free of visible soil, mica, and organic impurities, and the water extract of the filter media should not contain any toxic substances. The silt content should not exceed 1%, and the content of light materials with a density of less than 2 g/cm3 should not be more than 0.2% ； 　　3. The loss on ignition of the quartz filter media should not be greater than 0.7%, and its solubility in hydrochloric acid should not be greater than 3.5% ； 　　4. The effective particle size and coefficient of variation of the quartz filter media are determined by the user; alternatively, conditions can be specified for the manufacturer to provide them. Methods for laying the filter media and supporting material: 1. After the filter is installed, remove all debris first, then draw horizontal lines on the inner wall of the filter at the desired heights for each layer of supporting material and filter media, using these as markers for the laying height. Carefully inspect the backing materials of different particle size ranges, and clean them in descending order of particle size for use in paving. 　　2. When working on the layers of material, one should stand or walk on the bottommost layer of support material; it is advisable to work on wooden planks. The upper layer can be laid only after the line has been completed on the current layer. The thickness of each layer of backing material should be accurate and uniform, leveled using a scraper. The height should align with the horizontal line of the paving height. 　　3. After all the backing materials have been laid in layers, the filter material is then laid. The laying height of the filter media layer should also be level with the top surface of the filter media layer, and it should be leveled using a scraper. Technical requirements for gravel backing material: 1. Most of the particles in the gravel should be nearly spherical in shape ； 　　2. The gravel backing material shall be free of visible soil, shale, and organic impurities. The water leachate of the backing material shall not contain toxic substances. The mud content should not exceed 1%, and the solubility in hydrochloric acid should not be more than 5%. Operating instructions: 1. When the filter is started up for the first time, use a rubber hose to inject clean water into the water tank, allowing the water to flow through the filter from bottom to top via the connecting pipes, in order to remove any air from within the filter. 　　2. Before the initial backwashing of the filter, the flushing intensity regulator should be set to an opening degree of about one-quarter of the diameter of the siphon downpipe for the backwashing process; thereafter, the opening degree should be increased gradually until the specified flushing intensity is reached. 　　3. After the filter starts operating, it is necessary to regularly check whether the filter media are level and free from contamination; especially when used as a side filter for circulating cooling water, algae growth on the surface of the filter media can occur easily. If contamination is detected, the contaminated filter media on the surface (about 100 millimeters thick) should be removed and replaced with new filter media. Equipment Installation Instructions 　　1. The construction level of the equipment foundation is required to be accurate; level checking should be carried out again once the equipment is in place to ensure stable installation. The equipment is welded to the pre-installed steel plates in the foundation. 　　2. The water distribution tank and the top beam of the filter are connected by bolts, so as to adjust the two weirs to the same elevation level and ensure uniform water distribution. 　　3. The flange connections and threaded connections of the siphon system must be leak-proof, and strict attention must be paid to the control elevation at the tops of the siphon pipes and auxiliary pipes. 　　4. In addition to applying special anti-corrosion treatment to the interior of the equipment, the outer surface of the equipment should also be treated against corrosion after it has been installed; the color of this external anti-corrosion coating can be chosen by the user. Scope of the complete set supply: Serial Number, Name, Unit, Quantity, Remarks. 1. Water inlet distribution box: 1 piece. 2. U-shaped water inlet pipe fittings: 2 pieces. 3. Filters: 2 pieces, including a flushing tank and connecting pipes. 4. Siphon pipe fittings: 2 pieces, including a siphon auxiliary pipe and a drainage tank. 5. Fixing accessories for the water inlet tank and filters: 1 set. 6. Miscellaneous accessories: 1 set, including bolts, nuts, and gaskets required for the equipment. 7. Rubber flexible joint fittings: 1 piece, including connection flanges