You are the engineer asked to design a rapid sand filtration system for a small water treatment plant. it has the following characteristics: hydraulic loading rate = 6 m/h total volumetric flow rate of the plant = 3 mgd effective filtration rate = 5.8 m/h production efficiency = 97% complete (filtration, rinsing, and backwashing) filter cycle duration = 48 h.
a. what is the area of your square filtration system? what are the surface dimensions of the filter?
b. what volume of water is needed for backwashing plus rinsing the filter in each rinsing cycle?

Liquid flows at steady state at a rate of 2 lb/'s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. the liquid specific enthalpy at the inlet is 40.09 btu/lb and at the exit is 40.94 btub. the pump requires 3 btu/s of power to operate. if kinetic energy effects are negligible and gravitational acceleration is 32.174 tt/s, the heat transfer rate associated with this steady state process is most closely 1)-2,02 btu/s from the liquid to the surroundings 2)-3.98 btu/s from the surroundings to the liquid. 3)-4.96 btu/s from the surroundings to the liquid. 4)-1.04 btu/s from the liquid to the surroundings.