Abstract: A lifting set includes a lifting apparatus and a water treatment device. In lifting the water treatment device, an engaging member attached to a first attaching position of a frame of the lifting apparatus pivots in a first direction by sliding along a corresponding engageable portion of the water treatment device as the lifting apparatus approaches the water treatment device, and then automatically engages with the engageable portion by pivoting back to a vertical position by weight thereof while the lifting apparatus is further lowered. In installing the water treatment device, the engaging member attached to a second attaching position engages with the engageable portion at a pivoted position pivoted in a second direction, and when the lifting apparatus is further lowered after installation, the engaging member automatically disengages from the corresponding engageable portion by pivoting back from the second pivoted position to the vertical position by weight thereof.

Abstract: A lifting set includes a lifting apparatus and a water treatment device. In lifting the water treatment device, an engaging member attached to a first attaching position of a frame of the lifting apparatus pivots in a first direction by sliding along a corresponding engageable portion of the water treatment device as the lifting apparatus approaches the water treatment device, and then automatically engages with the engageable portion by pivoting back to a vertical position by weight thereof while the lifting apparatus is further lowered. In installing the water treatment device, the engaging member attached to a second attaching position engages with the engageable portion at a pivoted position pivoted in a second direction, and when the lifting apparatus is further lowered after installation, the engaging member automatically disengages from the corresponding engageable portion by pivoting back from the second pivoted position to the vertical position by weight thereof.

Abstract: A method for lifting a membrane separation device immersed in liquid to be treated so as to obtain permeated liquid passed through a filtration membrane provides a method for lifting the membrane separation device in a visible state without lowering the liquid level of a treatment tank. The method includes injecting a gas into a predetermined region of the membrane separation device, thereby raising the membrane separation device by a buoyancy generated by the injected gas through the liquid to be treated, and engaging an engaging portion of a lifting apparatus with an engageable portion provided to an upper portion of the membrane separation device, thereby lifting up the membrane separation device. The predetermined region may be a space constituting a flow path for the permeated liquid permeated through the filtration membrane.

Abstract: A method for lifting a membrane separation device immersed in liquid to be treated so as to obtain permeated liquid passed through a filtration membrane provides a method for lifting the membrane separation device in a visible state without lowering the liquid level of a treatment tank. The method includes injecting a gas into a predetermined region of the membrane separation device, thereby raising the membrane separation device by a buoyancy generated by the injected gas through the liquid to be treated, and engaging an engaging portion of a lifting apparatus with an engageable portion provided to an upper portion of the membrane separation device, thereby lifting up the membrane separation device. The predetermined region may be a space constituting a flow path for the permeated liquid permeated through the filtration membrane.

Abstract: A lifting apparatus capable of engaging with and disengaging from a water treatment device which is to be lifted without cumbersome manual operations is provided. The lifting apparatus includes a frame and an engaging portion pivotably attached to the frame by an upper portion thereof in a vertical position. The engaging potion is capable of engaging with an engageable portion of the water treatment device. The engaging portion is configured to be set to a first operation state in which the engaging portion pivots by contacting the engageable portion as the lifting apparatus approaches the water treatment device from above, and then pivots back to the vertical position as the lifting apparatus further approaches the water treatment device to become closer thereto, whereby the engaging portion and the engageable portion become engageable with each other.

Abstract: A membrane element 36 includes filtration membranes 45 on the flat part of the membrane element 36. Spacing members 60 keep spacing S between the filtration membranes 45 between the membrane elements 36 when the membrane elements 36 are arranged with the filtration membranes 45 opposed to each other. The spacing members 60 each have spacer sections 61a and 61b that keep the spacing S between the filtration membranes 45 between the membrane elements 36 in the direction of a membrane surface cleaning stream that flows along the surface of the filtration membrane 45.

Abstract: A membrane element 36 includes filtration membranes 45 on the flat part of the membrane element 36. Spacing members 60 keep spacing S between the filtration membranes 45 between the membrane elements 36 when the membrane elements 36 are arranged with the filtration membranes 45 opposed to each other. The spacing members 60 each have spacer sections 61a and 61b that keep the spacing S between the filtration membranes 45 between the membrane elements 36 in the direction of a membrane surface cleaning stream that flows along the surface of the filtration membrane 45.