Centrifugation is often used to thicken sludge solids. An incoming sludge with a solids concentration Co = 4% must be thickened to a solids concentration EC = 10% using a centrifuge. Unfortunately, the centrifuge produces a slurry that is 20% solids from 4% feed sludge, which means it is working too well. To avoid this, a portion of the feed sludge can be bypassed to later mix with the dewatered sludge (20%) to produce an effluent sludge with exactly 10% solids concentration. The tributary flow (Qo) is 1 gpm. The centrifuge produces a centrate (i.e., a low solids concentration effluent stream) with a solids concentration (SC) of 0.1% and a cake (the high concentrated effluent stream in solids) with a solids concentration (CK) of 20%. Find - All unknowns. All flow rates must be in gal/min and concentrations in g/cm3. Suppose - Specific Gravity is 1.0. Question 3 - An oil refining company wants to obtain permission to start an operation near a small piece of land. Before operation can begin, you, as the consultant, must confirm that the projected production of airborne particles would be less than 0.4 mg/m3. The area of interest is a 15 km by 15 km plot of land with an average ceiling height of 0.5 km. If the daily production of airborne particles is 185 kg/km2 and the average wind speed is 0.8 m/s, determine whether the projected production meets the requirements. Assume that the incoming air contains no particles, that particles are uniformly distributed throughout the projected area, and that steady-state conditions apply.

Answer rating: 100% (QA)

To determine whether the projected production of airborne particles meets the requirements we can ca... View the full answer