Automatic backwash muti tanks large sand filter for recirculating water system

Automatic backwash muti tanks large sand filter for recirculating water system

Principle descriptions

The Filtering Process

Filtering with media filters, also known as depth filtration, is done by filtering water through a thick layer of graded particles, called the filter bed. These particles can be sand, gravel or other granular materials. The filtration degree depends on the effective size of the bedding and the water velocity through the filter.

Raw water enters from the filter inlet (1) and percolates through the filter bed (2). Suspended materials come into contact and attach to the media particles. Clean water flows through the

filtration nozzles (3) and out of the filter via the outlet valve (4).

The gradual dirt buildup in the filter bed causes an increase in the pressure differential across the filter and when it reaches its maximum design value, a cleaning process should be performed. In automatic media filter installations a pressure differential switch senses the pressure differential and when it reaches a preset value, the self cleaning process begins.

The Cleaning Process

Cleaning is done by backwashing; pressurized water flows in reverse direction – from the nozzles upwards, causing suspension of the filter bed, thus releasing the suspended matter from the bedding. The dirt particles are then washed out of the filter through the back-flush valve. In automatic media filters installations the cleaning process is done by the system’s controller. When the pressure differential switch senses that the differential pressure across the system reached a pre-set value, a signal is sent to the flushing controller and the self cleaning process begins.

Technical parameters

 Data sheet(Each model with different size)

 (Note: Many sets in parallel can gain more flow.

  eg: DMF48-4 means there are 4 filtration tanks of 1200mm diameter in parellel)

DMF48-8 means there are 8 tanks in parellel)

Comparing with  traditional sand filter

Product selecting

When you are choosing automatic backwash sand filters, please consider the following parameters:

   1. Flow capacity( Pipe diameter)

   2. Filtration range

   3. Shell material

   4. Pipeline pressure 

   5. Chemical properties of the filter medium 

    6. Suspended solids(SS) concentration of filter medium 

 Product pictures

Application case:  cooling tower recirculating water bypass filtration

1. Our factory covers an area of 13000 square which is domestic largest water filter production base.

 2. The main products have self-cleaning filter,disc filter,sand filter etc.

3. We have a few professional engineers with over ten years experience in water filtration technology.

4. Our products have been widely used in circulating water,Ro pretreatment,agricultural irrigation,pre-treatment of sea water desalinization , wastewater treatment and so on.

Q: Where is your factory?
A:Changsha city,Hunan province, China

Q:Can you accept OEM?
A:Yes.We could do OEM for you.

Q: Do you have a certification?
A: Yes. we have ISO / CE certificate and certificate of patent.

Q: How about the delivery time?
A: Usually 7-15 days after prepayment is confirmed.

Q:Do you have a design team?
A:Yes,we have.Providing outline drawing,electric drawing and others.

Q:Can you send me a sample?
A: Yes.But it is not for free.


Q. :What is your payment?
A: T/T,T/C,Western Union,Paypal.


Q:How can I contact you?
A:You could contact me by email or Trademanager or others.

  We will select suitable model according to water source and actual situation.

 If you have any question, please don't hesitate to contact us.

Name: Grace

Tel:+86 0731843911   TAX:+86 0731 073185791635

Mob/whatsapp:+ +86 18573132583

Skype:gracewang199107

Email:gracewang199107(a)

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