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How does this relate to Pressure Differentials across a water filter?

How does this relate to Pressure Differentials across a water filter?

How does this relate to Pressure Differentials across a water filter?

(OP)
thread378-152951: Pump Power Consumption
Water filters will experience  increased head losses as they load up with debris. Flow will typically remain the same unless the filter becomes completely blinded. I'm trying to come up with an estimated power / energy cost associated with an increase of head loss or PD. I know there are pump efficiency considerations on each system but I am wondering if there is a way to compare two filtration systems (energy cost / kwh) based upon head losses through equal systems. I am considering what type of filtration system to use (500 gpm at 50 psi with 20 hp pump) and want to know how big of a cost impact one system will have over another based upon a 6 psi pressure differential between the two. There are many other factors to be considered (footprint, waste water...) in this cost analysis but I thought  I'd begin with head loss.

Look forward to your comments

RE: How does this relate to Pressure Differentials across a water filter?

Power cost is

dP = pressure differential psi
SG = specific gravity (water = 1)
den = 62/4 lbs/ft3  for water
Q = flowrate cfs

HorsePower = Q * dP_psi * 144 / (SG * den)/ 550

convert that to kW, and multiply by cost, $/kWh and multiply by how many hours it runs.

From "BigInch's Extremely simple theory of everything."

RE: How does this relate to Pressure Differentials across a water filter?

An even easier calculation -

flow = m^3/sec
dP = Pascals = N/m^2

Power (watts) = flow * dP

RE: How does this relate to Pressure Differentials across a water filter?

Oh, and in case it isn't obvious, don't forget to account for the efficiency of the pump and driver when calculating the actual input energy costs.  BigInch and I have given the hydraulic (flow) power loss, but there is a big loss associated with the pump used to create that hydraulic power, and the motor used to drive the pump, etc.

RE: How does this relate to Pressure Differentials across a water filter?

Install a backwash system and run it on a regular basis.  Saved a large beer make about $250,000 a month!!

RE: How does this relate to Pressure Differentials across a water filter?

Ick.  Who'd want backwash in their beer?

RE: How does this relate to Pressure Differentials across a water filter?

They back washed it to a drain.

BUT NEVER drink from my grand son's sippy cup or glass.  He has his own automatic backwash!!!

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