Completely mixed flow ractor CSTR and plug flow reactor (PFR) may have
significantly different efficiencies depending on the reaction order. This problem
asks you to compare the relative reactor sizes required to ensure 99.0 % removal of
wastewatwer pathogens. Wastewater from a city, which flows at a constant rate of
106 L/d, must be treated for coliform removal before it can be discharged to surface
waters. The initial coliform concentration is 250 mg/L and the rate constant for
coliform decay is given as k=2day(mg/L)1-i where i = reaction order
To compare the relative reactor sizes required for 99.0% removal of wastewater pathogens in a completely mixed flow reactor (CSTR) and a plug flow reactor (PFR), we need to calculate the residence time (θ) required in each reactor.
For a CSTR, the residence time can be calculated using the equation:
θ_CSTR = V / Q
where θ_CSTR is the residence time in the CSTR, V is the volume of the reactor, and Q is the flow rate of the wastewater.
For a PFR, the residence time can be calculated using the equation:
θ_PFR = V / Q
where θ_PFR is the residence time in the PFR.
To ensure 99.0% removal of wastewater pathogens, we need to determine the value of i, the reaction order, and then solve for the required residence times in both reactors.
Given that i = reaction order, we are missing the value of i in the problem statement. Once we have the value of i, we can proceed with the calculations.
Please provide the value of i or any additional information.