Calculating Volume of Water/Air Needed for Filter Backwashing

  • Thread starter Bashir2008
  • Start date
In summary: I do it quite often. It's hokey, but it works.In summary, the filter has a cross sectional area of 0.07065m2 and a volume of 0.1766m3. Some materials (beads) were put inside the filter in order to filter the water. The length of the filter is 2.5m and the diameter is 0.30m. The beads (materilas) inside the filter need to be washed from time to time and for this reason we use water or air for backwashing. My question is how could we know how much water or air that we have to pump it to the filter to clean these materials?
  • #1
Bashir2008
7
0
I have a filter for removal the impurities from the water.. this filter has a cross sectional area about 0.07065m2... and volume is 0.1766m3..

some materials ( beads ) were put inside the filter in order to filter the water.. the packed bed was around 0.60m length..and its volume was 0.046m3 of the filter..

The length of the filter is 2.5m and diameter is 0.30m

the beads ( materilas ) inside the filter need to be washed from time to time.. for this reason we use water or air for backwashing

My question: how could we know how much water or air that we have to pump it to the filter to clean these materials ?

You can make any assumptions if u need

I really need your help to solve this question.

Best regards
 
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  • #2
Bashir2008 said:
I have a filter for removal the impurities from the water.. this filter has a cross sectional area about 0.07065m2... and volume is 0.1766m3..

some materials ( beads ) were put inside the filter in order to filter the water.. the packed bed was around 0.60m length..and its volume was 0.046m3 of the filter..

The length of the filter is 2.5m and diameter is 0.30m

the beads ( materilas ) inside the filter need to be washed from time to time.. for this reason we use water or air for backwashing

My question: how could we know how much water or air that we have to pump it to the filter to clean these materials ?

You can make any assumptions if u need

I really need your help to solve this question.

Best regards

Use a flowmeter.

CS
 
  • #3
...or a bucket and a stopwatch.
 
  • #4
FredGarvin said:
...or a bucket and a stopwatch.

Ah...the poor man's flowmeter! :rofl:

I've actually done that before! :approve:

CS
 
  • #5
I do it quite often. It's hokey, but it works.
 
  • #6
I don't use a bucket, but a container that is graduated. That way I actually know how much water has been collected. :yuck:
 
  • #7
A 5 gallon bucket does surprising well.
 
  • #8
FredGarvin said:
...or a bucket and a stopwatch.

lmao. since we're all talking about buckets and stop watches... the most extreme bucket/stopwatch flow measurement I did was at a dock in Rotterdam. Found a rusty old 55 gallon drum that was dumped in a field. Took 20 seconds to fill it with sea water... That ruled out a pump problem for me! :smile:
 
  • #9
Sorry but you misunderstood me.. i did not mean how we measure the flow..

my question was : how could we know how much water we need exactly for this filter... and not how to measure it..
 
  • #10
Bashir2008 said:
Sorry but you misunderstood me.. i did not mean how we measure the flow..

my question was : how could we know how much water we need exactly for this filter... and not how to measure it..

Probably trial and error. You can obviously calculated the volume of water needed to flush the system, but the amount of time to flow through it in order to clean the beads would be a function of how dirty they are, what type of deposits are in the system, etc..

CS
 

1. How do I calculate the volume of water/air needed for filter backwashing?

To calculate the volume of water/air needed for filter backwashing, you will need to know the flow rate of your filter in gallons per minute (GPM) or cubic feet per minute (CFM), the duration of the backwash cycle in minutes, and the specific gravity of the media in your filter. The formula for calculating volume is: Volume = Flow rate x Backwash duration x Specific gravity.

2. What is the specific gravity of filter media and how do I determine it?

The specific gravity of a substance is the ratio of its density to the density of water. In the case of filter media, it is the ratio of the density of the media to the density of water. The specific gravity of most filter media ranges from 1.0 to 2.0, with sand having a specific gravity of 2.65. You can determine the specific gravity of your filter media by consulting the manufacturer's specifications or performing a simple density test.

3. Why is it important to calculate the volume of water/air for filter backwashing?

Calculating the volume of water/air needed for filter backwashing is important because it ensures that your filter is properly cleaned and maintained. Using the correct volume of water/air will help dislodge and remove trapped particles and debris, leading to better filtration and longer filter life. Additionally, using the correct volume will prevent wasting water/air and reduce energy consumption.

4. What are some factors that can affect the volume of water/air needed for filter backwashing?

The volume of water/air needed for filter backwashing can be affected by various factors such as the type and size of the filter, the type and amount of filter media, the condition of the filter, the flow rate of the filter, and the frequency of backwashing. It is important to regularly monitor these factors and adjust the volume of water/air accordingly.

5. Can I use a standard formula to calculate the volume of water/air for all types of filters?

No, different types of filters may require different formulas for calculating the volume of water/air needed for backwashing. For example, a sand filter may require a different formula than a cartridge filter. It is important to consult the manufacturer's specifications or seek guidance from a professional to determine the correct formula for your specific filter.

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