wastewater

· Anaerobic bio-transformation of chlorinated organics such as chloroform can be modeled using a second-order rate expression. The process is typically called co-metabolism, and it is typically assumed that the concentration of bacterial remains constant. If the second-order rate coefficient is 0.005 L/mg-d and the concentration of bacteria is 100 mg/L, how many days will it take for an initial concentration of chloroform to be reduced to 1% (i.e. 99% reduction).

2.

· Problem #2:Biotransformation of chlorinated organic compounds such as 1,1,1-trichloroethane can be modeled using a second-order rate expression. Given the following laboratory data for an experiment measuring the biotransformation of 1,1,1-trichloroethane by 100mg/L of bacteria, determine the pseudo-first-order rate constant and the second-order rate constant.

3.

· Following laboratory data represent the degradation of a insecticides in water. Do the data fit a zero-order, first order, or second order rate expression? Report the correct rate constant in correct units.

4.

· Wastewater being pumped into a 4.2 m diameter rank at the rate of 0.5 m3/min. At the same time, water leaves the tank at a rate that is dependent on the height of the liquid in the tank. The relationship governing the flow from the tank is:

· Question 1: If the tank was initially empty, develop a relationship that can be used to define the height of the liquid in the tank as a function of time. What is the steady state height of the liquid in the tank?

Question 2: Solve the above problem assuming the feed rate as 0.75 m3/min and the tank outflow is q = 2.7m2/min*h(m)

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