System for cooling inner cavity of spent fuel transportation container

The invention discloses a system for cooling an inner cavity of a spent fuel transport container, comprising: a gas-liquid separation tank, an inlet of the gas-liquid separation tank is connected with an outlet of the inner cavity of the transport container, and a first outlet of the gas-liquid separation tank is connected with a first pipeline; the cooling water treatment system is connected with a second outlet of the gas-liquid separation tank, an inlet of the cooling water treatment system is connected with the second outlet of the gas-liquid separation tank through a second pipeline, and an outlet of the cooling water treatment system is connected with an inlet of the inner cavity of the transportation container; the first valve is arranged on the first pipeline; the second valve is arranged on the second pipeline; the liquid level detection device is arranged in the gas-liquid separation tank and used for interlocking opening and closing of the first valve and the second valve according to detected liqu