PURPOSE: To provide a titled device compact in the entire shape and simple in mechanical construction, by providing plural partition boards used for flowing meanderlingly a liquid to a tank of the liquid to be purified, and providing an electrostatic liquid purifier to one of the boards.

CONSTITUTION: A contaminated liquid flowing in from a return port 6, is flowed meanderlingly through a flow passage formed by partition boards 7aW7b. At the partition board 7b, the liquid flows meanderlingly through a liquid passing part 7b' corresponding to the board 7b, and a part of the liquid passes in the inside of an electrostatic purifier 10 by a pressure difference between both side surfaces of the board 7b. The liquid passing through the purifier 10 is part of the whole liquid passing through a device, and is purified one at a time. Said constitution needs no large space for a liquid purifier at the outside of the device, then the device is made remarkably compact. Further a large flow resistance at the part 7b' makes the liquid also flow through the purifier 10 to surely purify it. Still more, the purifier 10 is constituted of earthed electrodes 11, 11', a high voltage electrode 12 disposed oppositely to the electrodes 11, 11', and a dust collecting body 13 consisting of a liquid permeable insulation material inserted between the electrodes 11, 11' and 12.