The liquids described in Prob. 2.4 are to be separated in a tubular centrifuge bowl with an inside diameter of 150 mm, rotating at 8,000 r/min. The free-liquid surface inside the bowl is 40 mm from the axis of rotation. If the centrifuge bowl is to contain equal volumes of the two liquids, what should be the radial distance from the rotational axis to the top of the overflow dam for the heavy liquid?

Prob. 2.4

A continuous gravity decanter is to separate chlorobenzene, with a density of 1,109 kg/m³, from an aqueous wash liquid having a density of 1,020 kg/m³. If the total depth in the separator is 1 m and the interface is to be 0.6 m from the vessel floor, 

(a) What should the height of the heavy-liquid overflow leg be;  

(b) How much would an error of 50 mm in this height affect the position of the interface?