Reactor core control device for FBR type reactor

The device of the present invention comprises a control line having a control pump and a control tank for injecting liquids for neutron reflectors to an annular tank disposed in a reactor container, a supply line having a supply pump and a supply tank for supplying the liquids for the reflectors to the control tank, a drain line having a control valve, a drain valve and a drain tank disposed to the annular tank and a make-up line for supplying the liquids for the reflectors from the drain tank to the control tank. Liquids such as water or oil for the neutron reflectors are injected in the annular tank disposed at the periphery of the reactor core to raise the level of the liquids in the tank and conduct burning in the reactor core. The liquid level may be controlled by an appropriate ON/OFF operation of a pump with no requirement for a motor or a driving device at a high accuracy and rotational portions. Periodical maintenances are not necessary. Reactor scram can be conducted only by opening the drain valve and the reflectors may be made of inexpensive materials. (N.H.)