pump settings

Question

PUMP SETTINGS A flowmeter (contacting head water meter) which generates a pulse every 10 gallons is connected to a timer which runs for 30 seconds every time it gets a pulse from the meter. The timer energizes a metering pump which has a maximum capacity of 22 gallons per day. The metering pump is dispensing a product which weighs 10 pounds per gallon. If 1 pound of product per 1000 gallons of water results in a dosage of 120 parts per million, at what percentage output (0 - 100%) must we set the metering pump to achieve a 600 part per million application rate? Show your calculations below. FlowMeter (1pulse/10gal)Timer (30 Seconds/Pulse) Pump (22 gal/24 Hrs)ChemicalWater

Answer 1

Given that, 1 pound of product per 1000 gallons of water results in a dosage of 120 parts per million
In other words, 120 parts per million dosage consists of 1000 gallons of water and 1 pound of product

Hence by rules of proportion, 600 parts per million dosage should consists of 1000 gallons of water and 5 pound of product

In other words, 600 parts per million dosage should consists of 5 pound of product in 1000 gallons of water 

By rules of proportion, 600 parts per million dosage should consists of 10 pound of product in 2000 gallons of water 

 

Also given that, the metering pump is dispensing the product weighing 10 pounds per gallon

Implies that, 600 parts per million dosage should consists of 1 gallon of product in 2000 gallons of water 

 

Given that, every 10 gallons of water creates a pulse.

Thus 2000 gallons of water creates 200 pulses.

Given that, 1 pulse runs for 30 seconds, hence 200 pulses runs of (30*200)= 6000 seconds = 100 minutes

 

Also, given that, the pulse runs the timer and the timer, in turn, energizes the metering pump over 30 seconds for each 10 gallon of water

Hence for 2000 gallons of water creating 200 pulse and running the timer for total 100 minutes, the metering pump must not dispense more than 1 gallon in every 100 minutes to achieve a 600 part per million application rate

In other words, the metering pump, in every 100 minutes, must not dispense more than 1 gallon

Hence. by rules of proportion, the metering pump, in 24 hr or 1440 minute  must not dispense more than 14.4 gallon

 

Given that, the metering pump dispenses at its full or 100% capacity, 22 gallon in 24 hrs or 22 gallons in 1440 minutes 

In other words, the metering pump, dispensing 22 gallon in 24 hrs is at its full or 100% capacity, 

By rules of proportion, the metering pump dispensing 14.4 gallon in 24 hrs is at its at its[(14.4/22)* 100]% capacity = 65.455 % capacity

 

Therefore, we must set the metering pump at 65.455 percentage output to achieve a 600 part per million application rate.