Problem 2 You need to design to filter for a 10,000-gallon fermenter that will be aerated at a rate of 535 ft /min (20C, 1 atm). The bacterial count in the air is 80 per ft. Average size of the bacteria is 1 um with density of 1.08 g/cm. You are going to use glass fibers (D = 15 m) with packing density a = 0.03. The cross-sectional area of the filter will be designed to give a superficial air velocity u, of 5 ft/s. a. What depth of the filter would you recommended to prevent contamination? b. How is the answer in (a) changed if u, is decreased to 1 ft/s ? Explain the results.