Patent ID: 8377303

Claim:
A membrane cartridge constituting a submerged membrane separator, the membrane cartridge comprising: a filtration membrane provided at least on one surface of a filtration plate; a channel groove pattern formed on the surface of the filtration plate covered with the filtration membrane, the channel groove pattern allowing passage of a permeated liquid having passed through the filtration membrane; and a permeated liquid outlet provided on a circumferential edge of the filtration plate, the permeated liquid outlet collecting and taking out the permeated liquid having passed through the channel groove pattern, wherein the channel groove pattern comprises multiple channel grooves, the filtration plate comprises a pressure difference reduction groove crossing an area where the channel groove pattern is formed, the area where the channel groove pattern is formed is divided into multiple water collection areas by the pressure difference reduction groove, the pressure difference reduction groove communicates with the permeated liquid outlet only through the channel grooves, and the pressure difference reduction groove has a channel cross-sectional area larger than the cross-sectional area of the channel groove.