Convert flow rate to total volume

I need to measure the volume of water used in during water intake phase of a CIP (washing program) in order to insure that there is a specific amount of water in the system before starting the circulation pump.
Unfortunately my controller doesn't have high speed input for the flowmeter's pule output so I'm thinking of getting the 4-20mA version of the flowmeter.

Characteristic line formula for current output of flowmeter is:
QV = KI * (IOUT - 4 mA)

Where:
QV Volume flow rate [l/min]
KI Coefficient current output [(l/min) / f]
IOUT Current [mA]

Is it possible to calculate the total volume?
For example if I need to close the water valve when there is exactly 30l of water in the circuit.

Once per second, multiply the flow rate in liters per minute by 1/60 (fraction of a minute) to get liters. Add that amount to a running total.
You can do the arithmetic more or less often if you want.

If your using ControlLogix it has a nice Totalizator instruction that works very well. It's a Flow Chart only, but I just dropped one on a AOI Flow chart and used it in Ladder logic.

If your PLC has an integral or integrator, that would work as well. You will need to setup some parameters for summing over time. It's been over a decade since I've used this method so I can't remember exactly how this is done. Hope this helps!