For which one of the following situations would Kendall’s tau be appropriate? a) The Mohs scale rates the hardness of minerals. If one mineral can scratch another, it is judged….
Calculate the area and T1. Then, calculate the actual feed rate by multiplying 1000 by 1000/calculated area.)
Evaporation in Double-Effect Reverse-Feed Evaporators. A feed containing 2 wt % dissolved organic solids in water is fed to two double-effect evaporators with reverse feed. The feed enters at 100°F and is concentrated to 25% solids. The boiling-point rise can be considered negligible, as can the heat of solution. Each evaporator has a 1000-ft 2 surface area, and the heat-transfer coefficients are U1 = 500 and U2 = 700 btu/h · ft 2 · °F. The feed enters evaporator number 2 and steam at 100 psia is fed to evaporator number 1. The pressure in the vapor space of evaporator number 2 is 0.98 psia. Assume that the heat capacity of all liquid solutions is that of liquid water. Calculate the feed rate F and the product rate L1 of a solution containing 25% solids. (Hint: Assume a feed rate of, say, F = 1000 lbm/h and a value of T1. Calculate the area and T1. Then, calculate the actual feed rate by multiplying 1000 by 1000/calculated area.)