Question

For a hardness of 5.0meq/L, what flowrate should be treated by ion exchange so that the total product water flowrate of 10 m 3

/ day has a hardness of 2meq/L ? a) 4.6 m^3
/ day b) 5.0 m^3
/ day c) 6.4 m^3
/ day d) 6.0 m^3
/ day c) 5.6 m^3
/ day 23. What is the mass of moist resin required if the dry resin exchange capacity is 4 meq/g, the moisture content is 0.50, the resin is regenerated every 2 days, and you apply a safety factor of 1.5 ? a) 38 kg b) 45 kg - c) 62 kg d) 53 kg e) 30 kg 24 . With three ion exchange columns in parallel and a surface loading rate of 200 m/ day, what is the diameter of each column? a) 10.3 cm b) 12.7 cm c) 11.6 cm d) 11.3 cm 25 . With a moist resin density of 750 kg/m 3
, what is the minimum height of the columns? a) 1.8 m b) 2.7 m c) 1.6 m d) 2.0 m
Previous question

Answer 1

For a hardness of 5.0 meq/L, the flowrate to be treated by ion exchange can be calculated using the following equation:

Flowrate treated = (Hardness in feed water - Desired hardness in product water) * Total product water flowrate / Hardness in feed water

Using the given values, the calculation is as follows:

Flowrate treated = (5.0 - 2.0) * 10 m^3/day / 5.0 meq/L

Flowrate treated = 3.0 * 10 m^3/day / 5.0 meq/L

To convert meq/L to m^3/day, we need to consider the conversion factor. Since 1 meq/L is equal to 0.001 m^3/day, we can use this conversion factor:

Flowrate treated = 3.0 * 10 m^3/day / (5.0 meq/L * 0.001 m^3/day/meq/L)

Flowrate treated = 3.0 * 10 m^3/day / 0.005 m^3/day

Flowrate treated = 6000 m^3/day / 0.005 m^3/day

Flowrate treated = 1200000 m^3/day

Therefore, the flowrate that should be treated by ion exchange to achieve a total product water flowrate of 10 m^3/day with a hardness of 2 meq/L is 1200000 m^3/day.

Regarding the second and third questions, the information provided is not sufficient to perform the calculations. Please provide the missing information for the mass of moist resin and the diameter of each column so that I can assist you further.