The invention belongs to a
nuclear fuel preparation method, and specifically discloses a method for collecting UF6, which includes: inputting the UF6 gas mixture obtained by the gas-
solid reaction of UF4 and F2 in a vertical fluorination furnace into a first-stage internal cooling and
internal heating UF6 condenser, and passing through After condensing and separating most of the UF6, it is then input into the secondary internal cooling and
internal heating UF6 condenser to condense and collect the remaining UF6, and the residual gas enters the
exhaust gas treatment system to be purified and then emptied; among them, the
refrigerant in the internal circulation
pipe of the primary condenser is demineralized water , The temperature for receiving UF6 gas is 5-10°C. The present invention adopts demineralized water with low
corrosion and no scaling as the secondary
refrigerant of the first-stage internal cooling and
internal heating type UF6 condenser, which reduces the
corrosion of the internal circulation
pipe of the internal cooling and internal heating type condenser; the temperature of the receiving gas is changed to 5-10 ℃, reduce the
working temperature difference of the internal circulation
pipe and reduce the stress
corrosion of the internal circulation pipe. The
working life of the condenser is extended to more than 1238tU, and the service life can reach more than 10 years; and the UF6 collection rate can still reach more than 99.6%.