With its unique shallow - layer filtration structure and efficient backwashing technology, it achieves rapid interception of impurities and continuous and stable water purification, making it an optimal solution for water treatment in industrial and civil fields.

I. Product Introduction

The shallow sand filter is a high - efficiency water treatment device developed based on the principle of shallow - layer media filtration. High - quality quartz sand is filled inside the device as the filtration medium. Through the optimized design of the shallow - layer filter bed, the water flow is evenly distributed in the filter layer, greatly improving the filtration efficiency. It can effectively remove impurities such as suspended solids, sediment, and colloids in water, reduce water turbidity, and ensure the safe and stable operation of subsequent water - using equipment. The device is equipped with a full - automatic control system, which can realize the intelligent switching of processes such as filtration and backwashing. It is easy to operate and has a low maintenance cost, and is widely used in many fields such as industrial circulating water, municipal water supply, and sewage treatment.

II. Working Process

1. Filtration Stage:

• Raw Water Inflow: The raw water to be treated enters the device from the top inlet of the filter under the pressure of the water pump and spreads evenly to the shallow - layer quartz sand filter bed.

• Impurity Interception: The water flows through the quartz sand filter layer from top to bottom, and impurities such as suspended solids, sediment, and colloids are intercepted by the pores between the filter media particles. The purified water flows out from the bottom outlet of the filter and enters the subsequent water - using links.

2. Backwashing Stage:

• Trigger Conditions: When the pressure difference between the inlet and outlet of the filter reaches the set value (generally 0.05 - 0.1MPa), or the running time reaches the preset duration (such as 8 - 12 hours), the system automatically starts the backwashing program.

• Water Flow Reversal: After the backwashing starts, the drain valve opens, and the water flow direction is reversed, entering from the bottom of the filter and flushing the filter layer at high speed. At the same time, the water distributor rotates to make the backwashing water flow act more evenly on the filter media, and the intercepted impurities are discharged from the top sewage outlet.

• Filter Media Cleaning: The high - speed water flow makes the quartz sand filter media in a fluidized state, rubbing and colliding with each other, thoroughly removing the impurities attached to the surface and restoring the filtration performance of the filter media.

• Resuming Operation: After the backwashing is completed, the system automatically closes the drain valve and enters a short forward flushing stage. After the effluent water quality meets the standard, it switches back to the filtration mode.

III. Product Features

IV. Technical Parameters

V. Application Fields

1. Industrial Circulating Water Systems：

• Cooling Circulating Water：In the cooling circulating water systems of enterprises such as power plants, chemical plants, and steel plants, it filters impurities such as suspended solids and microbial slime in the water, prevents pipeline blockages and equipment corrosion, improves cooling efficiency, and reduces energy consumption.

• Process Circulating Water：It ensures the stable water quality of process circulating water in industries such as papermaking, printing and dyeing, and food processing, removes impurities such as fibers, pigment particles, and food residues generated during the production process, and improves product quality.

2. Municipal Water Projects：

• Pretreatment in Waterworks：As a primary filtration device for raw water in waterworks, it removes large - particle pollutants such as sediment and algae in the water, reduces the burden on subsequent treatment processes, and improves the quality of the treated water.

• Advanced Sewage Treatment：After the secondary treatment in sewage treatment plants, it further filters the residual suspended solids in the water, making the effluent meet the reuse standards for municipal miscellaneous water, landscape water replenishment, etc.

3. Agricultural Irrigation Field：

• Sprinkler and Drip Irrigation Systems：It filters sediment, weed debris, etc. in irrigation water, prevents the blockage of sprinkler heads and drip irrigation tapes, ensures uniform irrigation, improves irrigation efficiency, and protects crop growth.

• Aquaculture：It purifies the circulating water in aquaculture ponds, removes impurities such as feces and uneaten bait in the water, improves water quality, creates a good environment for aquaculture, and reduces the occurrence of diseases.

4. Commercial and Civil Buildings：

• Central Air - Conditioning Circulating Water：It filters the impurities in the chilled water and cooling water systems of central air - conditioners, prevents the scaling and blockage of heat exchangers, extends the service life of equipment, and reduces operating costs.

• Domestic Water Purification：In places such as residential areas and hotels, it conducts preliminary filtration of domestic water, improves water quality, and ensures the safety of residents' water use.

VI. FAQ

1. Is the backwashing water consumption of the shallow sand filter large?No. The shallow sand filter adopts an efficient backwashing design, and the backwashing water consumption is only 1 - 3% of the treated water volume. Compared with traditional filters, its unique water distribution and backwashing technology enable the water flow to precisely flush the filter layer, effectively removing impurities while greatly reducing water waste.

2. What should be done if the effluent turbidity of the device exceeds the standard?First, check whether the backwashing trigger conditions are met. If the filter layer is blocked due to untimely backwashing, the backwashing program can be manually started. If the effluent turbidity still does not meet the standard after backwashing, check whether the filter media has been lost or damaged, or whether the water distribution system is abnormal. In addition, sudden changes in raw water quality may also affect the effluent turbidity, so the raw water condition needs to be investigated simultaneously.

3. Can the device operate outdoors for a long time?Yes. The device materials of the shallow sand filter can be carbon steel lined with rubber or stainless steel, which have good weather resistance and corrosion resistance. However, when used in extremely cold areas, anti - freezing measures should be taken for pipes and valves to avoid equipment damage caused by low temperatures and ensure normal operation.

VII. Conclusion

The shallow sand filter provides reliable water purification solutions for various industries with its efficient and fast filtration performance, intelligent and energy - saving operation mode, and wide application adaptability. Whether it is for the stable water supply in industrial production or the water guarantee in municipal and civil fields, it can complete the task excellently. Choosing our shallow sand filter means choosing an efficient, intelligent, and economical water treatment solution, helping users achieve the dual goals of water quality improvement and cost optimization.

VIII. Related Products

Basket filter

https://www.le-filter.com/wastewater-treatment/basket-filter/

High flow filter element

https://www.le-filter.com/water-filter-element/high-flow-filter/