The formula is actually very simple.
It is water flowrate x ozone dosage = required ozone production.
Below is the formula for determining ozone generation requirements if you know common water and ozone parameters (namely flowrate in GPM and ozone dosage in mg/l).
flowrate (GPM) x 3.78 l/gal x 60 min/hr x ozone dosage (mg/l) = ozone production (mg/hr)
Lets work through an example. How much ozone production is needed to dose 2 PPM into 20 GPM of water? (we will be using PPM throughout the rest of this example knowing that 1 mg/l = 1 PPM)
20 GPM x 3.78 l/gal x 60 min/hr x 2 PPM = 9,072 mg/hr (9 gm/hr)
Remember that 9 gm/hr will permit you to dose the water with 2 PPM of ozone. This does not mean that 2 PPM will be your final dissolved ozone concentration. Due to efficiency losses with injecting ozone and ozone demand of the water, your dissolved ozone concentration will be less.
The formula is flowrate (lpm) x ozone concentration (g/m3) = ozone production (mg/hr)
Let's work through an example: The ozone concentration exiting an ozone generator is 120 g/m3 at 5 lpm of oxygen flow. What is the output?
5 l/min x 120 g/m3 x (1 m3/1,000 l) = 0.60 g/min
g/min are not normal units in the ozone industry so we simply convert minutes to hours to get g/hr: 0.60 g/min x 60 min/hr = 36 g/hr
Convert 140 g/m3 to wt% (oxygen feedgas).
based on the conversion above, 100 g/m3 = 6.99 wt. %
based on the conversion above, 100 g/m3 = 6.99 wt. %