The last section of this chapter describes the sizing of a heat exchanger to cool the neutralized acid stream from 49.9°C to 27°C using cooling water available at 15°C. That calculation assumed an outlet temperature of 22°C for the cooling water. In contrast, this problem assumes that the outlet temperature of the cooling water can be as high as 27°C.

The last section of this chapter describes the sizing of a heat exchanger to cool the neutralized acid stream from 49.9°C to 27°C using cooling water available at 15°C. That calculation assumed an outlet temperature of 22°C for the cooling water. In contrast, this problem assumes that the outlet temperature of the cooling water can be as high as 27°C.
a. Set up a spreadsheet to calculate the volumetric flow rate of cooling water and area of the heat exchanger required to cool the outlet stream from the acid neutralization process. Perform the calculations for a range of cooling water outlet temperatures from 16 to 27°C in one-degree increments, assuming a countercurrent heat exchanger.
b. Graph the results from (a) (cooling water flow and heat exchanger area as a function of cooling water outlet temperature) and provide a brief qualitative explanation of the observed behavior.
c. Repeat the calculations and graphs from(a) and (b) for a co-current heat exchanger. (Caution: For this case, can the cooling water outlet temperature for this heat exchanger actually equal 27°C?)
d. Based on the above calculations, which type of heat exchanger (countercurrent or co-current) would you recommend? Why?