A 1000 MW fission reactor consumes half of its fuel in 5.00 y. How much 23592U did it contain initially? Assume that the reactor operates 80% of the time, that all the energy generated arises from the fission of 23592U and that this nuclide is consumed only by the fission process.
Half-life of the fuel in the fission reactor = 5 years
= 5 × 365 × 86400 s (∵ 1 day = 86400 seconds)
= 1.576 × 108 sec
∵ 1 gm of Uranium fission gives 200 MeV energy [This can be worked out from the fission equation given below of Uranium].
∴ 1 gm of Uranium, =
Energy generated by Uranium fission =
= J
= 8.2 × 1010 J/gm
∵ The 1000MW reactor operates only 80% of it’s time,hence in 5 years amount of uranium consumed
=
= 1538 kg
∴ This amount is consumed within the half life time.
Hence, the initial amount will be = 2 × 1538Kg
= 3076Kg