Asedimentation basin is used to remove suspended solids from a wastewater. the rate of flow of wastewater into the tank is 10 l/s, and the influent concentration of suspended solids is 200 mg/l. the removal efficiency of the settling tank for suspended solids is 60%. calculate the amount of suspended solids (sludge) accumulating in the sludge zone each day. you may assume that the amount of water withdrawn when pumping out the sludge from the sludge zone is very small compared to the inflow of wastewater to the tank and can therefore be ignored.

Water at 55c flows across a flat plate whose surface temperature is held constant at 95c. if the temperature gradient at the plate's surface for a given value of x is 18 c/mm, find a) local heat transfer coefficient. b) heat flux

Atmospheric air has a temperature (dry bulb) of 80° f and a wet bulb temperature of 60° f when the barometric pressure is 14.696 psia. determine the specific humidity, grains/lb dry air. a. 11.4 c. 55.8 d. 22.5 b. 44.1

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.