LIQUID FILTER DEVICE AND BALLAST WATER TREATMENT DEVICE USING SAME

摘要

This liquid filter device is provided with: a filter membrane unit; a washing means that washes a filter surface of the filter membrane unit from a side to which liquid to be filtered is supplied; and a pressure detection means that detects the difference in pressure before and after filtering by the filter membrane unit. The filter membrane unit is provided with a double filter membrane. In addition, the liquid filter device is used as a filter device for seawater and has been made into a ballast water treatment device mounted in a marine vessel.