The purpose of the present invention is to collect an oil from a crude oil sludge de-sludged from a tank in a larger quantity and more efficiently while improving various problems arising during the de-sludging of the crude oil sludge from the tank, and to reduce or eliminate a crude oil sludge without needing to halt the operation of a crude oil tank. A crude oil processing device (100) is provided with: tanks (1 to 5) in each of which a crude oil (O) containing a crude oil sludge (S) is stored; and a processing unit (8) in which the crude oil (O) is processed by applying a voltage to the crude oil (O) fed from the tanks (1 to 5) to produce an electrostatic field.
