Many chemical plants store fuel oil in a “tank farm” on the outskirts of the plant. To prevent an environmental disaster, there are specific rules regarding the design of such facilities. One such rule is that there be an emergency dump tank with the capacity of the largest storage tank. Should a leak or structural problem occur with a tank, the fuel oil can be pumped into the emergency dump tank.

Consider the design of the pumping system from a 250 m³ tank storing #6 fuel oil into a 250 m³ dump tank. The viscosity of #6 fuel oil is 0.8 kg/m³ s, and its density is 999.5 kg/m . The piping system consists of 43 m of commercial-steel pipe, four 90°

flanged regular elbows, a sharp entrance, an exit, and a pump. The oil must be pumped to an elevation 3.35 m above the exit point from the source tank.

If 20-in, schedule-40, commercial-steel pipe is used, and if it is necessary to accomplish the transfer within 45 min, determine the power rating required of the pump. Assume the pump is 80% efficient.

If the pump to be used has 10 kW at 80% efficiency, and the pipe is 20-in, schedule-40, commercial-steel pipe, determine how long the transfer will take.

If the pump to be used has 20 kW at 80% efficiency, and the transfer is to be accomplished in 45 min, determine the required schedule-40 pipe size.