Radon from well water may pose a radiological health hazard. One treatment technique is simply to hod the water in storage, allowing the radon to decay. The decay rate is first order:
Rn---> Products ; k= 0.2day^-1
Consider a situation in which water is delivered from a well to a household at a rate of 1m^3/day . The radon concentration is to be reduced by storage to 7 percent of its level in the untreated supply.
a. How large must the storage tank be if it acts a plug-flow reactor?
b. How large must the storage tank be if it acts a completely mixed flow reactor?
c. If the storage tank system consists of two identical CMFRs in series, how large must each be to achieve the desired level of control?