Shallow Sand Media Filter

Natural sea sand serves as the filter material in the shallow medium filter. A high-efficiency filtration device that lowers water turbidity and improves water quality is eventually achieved by passing water with high turbidity through a certain thickness of granular or non-granular natural sea sand, which effectively intercepts and removes suspended solids, organic matter, colloidal particles, microorganisms, chlorine, smell, and some heavy metal ions, etc.

The completely automated shallow sand filter features a spherical shell and an original internal structure design to guarantee high filtration performance and smooth water flow during filtration. Internal circulations are formed during backwashing, which has a significant backwashing impact. Its benefits over the conventional sand filter include automated filtering, automatic backwashing, using less sand, and using less water.

Working Principle

When the system is filtering, unfiltered water moves via the upper water distributor, works with the spherical shell, and moves nearly advectively until it reaches the packing layer in the filter. Impurities are held in the packing layer and are trapped when water passes through it. The filtered water is uniformly collected and discharged via the collector at the bottom of the filter. Advection filtration establishes that even with a high flow rate, the filter can still produce a good filtration effect.

The head loss (i.e., the differential pressure) will continue to rise as long as contaminants are allowed to build up in the packing layer. when the difference in pressure approaches.

The system automatically switches to the backwash mode to clean the packing layer and eliminate the collected contaminants when a specific set limit is reached or the filtration duration exceeds the specified value. The system has to be backwashed often to get rid of the accumulated pollutants. Purities are required.

Through PLC control, the three-way valve's on-off position is modified when the system enters the backwash condition (the intake is closed, the discharge

A portion of the filtered water from other filter tanks flows into the filter tank to be backwashed when the sewage port is opened. The water flow washes up the packing layer of the filter unit that has been backwashed by the system pressure, and the contaminants are then expelled through the three-way valve's sewage outlet.

The BTSL system's specifically created water collector causes the packing layer to develop an inner circulation while it is being backwashed, and the packings are cleaned alongside one another. This increases the effectiveness of the backwashing process and lowers the amount of backwashing water needed. run the content. The next filter unit enters the backwash state when the backwash is finished, and the valve returns to the filter state. In order to assure continuous flow during backwashing, a system typically comprises of many filter tanks (units), which are backwashed one after the other.

Features

1) The filter contains two viewing and inspection openings; the top is for feeding and observation, and the bottom is for emptying and upkeep. Each port features an entirely leak-proof construction. The system uses the secure and dependable hydraulic sealing concept.

2) Each component of the system's 55 distinct mushroom-shaped differential pressure compensation filter water collectors measures the water pressure level while it is filtering.

In the backwashing condition, an internal circulation forms and the backwashing efficiency is high and does not run off sand. It is balanced, has a high filter flow rate, and is highly effective.

3) The water distributor maintains a flat water surface on the packing layer and ensures that the unfiltered water flows uniformly through the packing layer even when there is a high flow.

4) The filter housing has a high efficiency, high pressure-to-weight ratio, and corrosion resistance. It is constructed of stainless steel, steel lined with rubber, or all plastic. The integrated spherical shell has a 0.59Mpa pressure tolerance.

5) The inner layer of the filter is constructed of black polyethylene, which is resistant to chemical attacks, embrittlement, and environmental pressure.

6) In order to maintain a constant pressure from each water collector to the outlet, the pressure-compensated water collector has tiny openings near the middle and wide openings towards the tail.

7) Power savings: The system features a special automated backwash valve that prevents the backwash of the sand filter tank from occurring simultaneously. Instead, under normal system operation, backwashing is carried out one at a time, negating the need to set up a backwashing pump. The filtration pump's necessary lift is also 6-7 meters lower than that of other sand filtration apparatus.

8) Water conservation: Because the system includes a single specification tank and a special water replenisher and water collector, the medium layer may be evenly extended for efficient backwashing without the need of compressed air. The amount of water required for backwashing is minimal because it is pure, filtered water. A single tank's backwash water flow is just 1.3m/min, and the backwash duration is 60S.

9) Lower maintenance costs: Only the one special multi-function valve is utilized to regulate the system's backwashing; the entire system is devoid of any mechanical or electric valves. Due to the special multi-function valve's extended lifespan, lack of damage records within ten years, and cheap administration expenses, it has no wear.

Application Range

Applications for inlet water filtration, cooling circulating water, seawater filtration, reuse water, sewage filtration

Technical Parameter

The BTSL shallow sand filter can be used with a variety of common filter media, but mainly natural sea sand is used and, depending on the filtration requirements, two types of natural sea sand are recommended for accuracy.

Design water inlet pressure: 0.2-0.4Mpa

Backwash water flow: 35-55m³/h

Working pressure: ≤0.6Mpa

Backwashing water consumption: <1% of filtration volume

Inlet and outlet water quality: SS=15-30mg/L

Backwashing method: internal source backwashing (except single continuous body)

Discharge water quality: SS≤5mg/L

Control mode: time and differential pressure dual control

Pressure loss: ≤0.1Mpa