| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive membrane cartridge capable of increasing fatigue-resistant strength by a simple configuration by focusing on an inside shape of a part for joining a filtration membrane to a filter plate.SOLUTION: In a membrane cartridge 8, a filtration membrane 10 is joined to a surface of a thermoplastic resin filter plate 9 by a joint 11 of its peripheral edge. A protrusion 13 higher than the joint 11 is formed in the thickness direction of the filter plate 9, on the inside near an inner edge end P1 of the joint 11 of the surface of the filter plate 9. A tangent to the protrusion 13 from the inner edge end P1 of the joint 11 is inclined by an angle of 10 degrees or more with respect to a direction parallel to the surface of the filter plate. |
