Problem Statement: An above-ground tank, 20 ft. tall and 20 ft.in diameter, at Freedom Industries in...

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Problem Statement: An above-ground tank, 20 ft. tall and 20 ft.in diameter, at Freedom Industries in Charleston, WV was leaking a mixture of crude methylcyclohexanemethanol (MCHM) and polyglycol ethers through two small holes, 0.75" and 0.4" in diameter, near the floor caused by pitting corrosion. These chemicals traveled down a descending bank into the adjacent Elk River and also contaminated the surrounding soil. The secondary containment or the dike wall that was put in place, did not control the leak due to cracks and holes from disrepair. The nearly 11,000 gallon leak left around 300,000 people without drinking water. Assume that the concentration of MCHM in the fluid exiting the tank is much higher that the concentration of polyglycol. Mass flow rate of MCHM in the river before mixing is negligible. Assume the density of the liquid, p, in the tank to be constant and equal to 867 kg/ Discharge m³. Coefficient, Co, for both the holes is 0.61. (b) At t=0 the corrosion pitted spots popped open and the liquid began to flow out of both holes at the bottom. If the height of fluid in the tank is initially 18ft., calculate the volumetric flow out of each hole at t = 0. The gauge pressure inside of the tank above the fluid is Pg = 8 kPa and the pressure outside the holes is 101kPa (1 atm). (Hint: First solve for exit velocity of liquid using Bernoulli's equation. Then multiply exit velocity with discharge coefficient to incorporate frictional losses.) (c) Calculate the height of liquid in the tank as a function of time, and solve for the time taken for 11,000 gallons of liquid to leak from the holes. (d) Assuming the volumetric flow rate of the Elk River is 1,000 gals/minute and MCHM is instantaneously mixed in the river at the point of entry, calculate the concentration of MCHM at the point of entry in the river as a function of time. Problem Statement: An above-ground tank, 20 ft. tall and 20 ft.in diameter, at Freedom Industries in Charleston, WV was leaking a mixture of crude methylcyclohexanemethanol (MCHM) and polyglycol ethers through two small holes, 0.75" and 0.4" in diameter, near the floor caused by pitting corrosion. These chemicals traveled down a descending bank into the adjacent Elk River and also contaminated the surrounding soil. The secondary containment or the dike wall that was put in place, did not control the leak due to cracks and holes from disrepair. The nearly 11,000 gallon leak left around 300,000 people without drinking water. Assume that the concentration of MCHM in the fluid exiting the tank is much higher that the concentration of polyglycol. Mass flow rate of MCHM in the river before mixing is negligible. Assume the density of the liquid, p, in the tank to be constant and equal to 867 kg/ Discharge m³. Coefficient, Co, for both the holes is 0.61. (b) At t=0 the corrosion pitted spots popped open and the liquid began to flow out of both holes at the bottom. If the height of fluid in the tank is initially 18ft., calculate the volumetric flow out of each hole at t = 0. The gauge pressure inside of the tank above the fluid is Pg = 8 kPa and the pressure outside the holes is 101kPa (1 atm). (Hint: First solve for exit velocity of liquid using Bernoulli's equation. Then multiply exit velocity with discharge coefficient to incorporate frictional losses.) (c) Calculate the height of liquid in the tank as a function of time, and solve for the time taken for 11,000 gallons of liquid to leak from the holes. (d) Assuming the volumetric flow rate of the Elk River is 1,000 gals/minute and MCHM is instantaneously mixed in the river at the point of entry, calculate the concentration of MCHM at the point of entry in the river as a function of time.

Answer rating: 100% (QA)

a 1The concentration of MCHM in the fluid exiting the tank is much higher that the concentration of polyglycol 2 Mass flow rate of MCHM in the river before mixing is negligible 3 Discharge Coefficient ... View the full answer