silo 3 - U.S. Department of Energy

3. Convevor Tor> and Bottom
EN G I N E E R I N G@
Project:
Calculation Number: 40430-CA-0003
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In addition to the radon released from the processed silo material in the retrieval bin, radon continues
to be generated in the downstream conveyors. The radon generation rate is a function of the amount
of solid material in each component.
The conve or bottom measures approximately 12 in. x 12 in. x 20 ft. At a volume of 20 ft3 and density
of 50 Ibht 3 , the material mass is approximately 1 .OOO Ib.
The inclined conveyor measures approximately 12 in. wide, 3 in. deep, and 70 ft. long, for a volume of
17.5 ft3 and material mass of approximately 875 Ib.
Assuming an emanation rate of 0.35, the radon generation rates from the inclined conveyor during
Phase 2 are: ._
R = 925 pCi/g 223Ra x 454 g/lb x 0.693/0.067 min x 875 Ib x 0.35
R = 1.33 x 10' DCi/min 2''Rr\
R = 367 pCi/g "4Ra x 454 g/lb x 0.693/0.9237 rnin x 875 Ib x 0.35
R=3.83 x 10 ' ~Ci/min "'Rn
R = 3870 pCVg "%a x 454 gAb x 0.693/5500 rnin x 875 Ib x 0.35
R = 6.78 x lo4 DCi/min =Rn
The radon generation rate from the conveyor bottom during Phase 2 is:
R = 925 pCVg 223Ra x 454 glib x 0.69W0.067 min x 1000 Ib x 0.35
R = 1.5 x 10' r>Ci/min 2'sRn
R = 367 pCig 224Ra x 454 gllb x 0.69W0.9237 rnin x 1 OW Ib x 0.35
R = 4.38 x 10' DCi/min =Rn
R = 3870 pCVg =Ra x 454 glib x 0.693/5500 min x 1 OOO Ib x 0.35
R=7.75 ~ 1' DC'imin 0 =Rn
a '.' . . . Q00220
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