Abstract: A hollow fiber membrane module in which a housing body forming the hollow fiber membrane module includes an insertion opening into which end parts of the plurality of hollow fiber membranes are inserted so as to be fixed and held, and an opening portion which exposes open end surfaces of a plurality of hollow fiber membranes inserted from the insertion opening to outside, and a cover that blocks the opening portion of the housing body. According to the present invention, it is possible to provide a housing enabling open end surfaces of hollow fiber membranes to be sealed by easily exposing the open end surfaces of the hollow fiber membranes when the hollow fiber membranes are damaged.

Abstract: The present invention relates to an air diffusion device comprising a tubular main pipe for receiving a supply of air from an air supply device, and a branch pipe connected to the main pipe, wherein the branch pipe is connected at one end to the main pipe and open at the other end, one or more air diffusion holes are formed in the branch pipe, at least some of the air diffusion holes are formed so as to be at the top in the vertical direction when the main pipe is laid horizontally, and the branch pipe is configured so that the opening at the other end faces downward in the vertical direction. According to the present invention, it is possible to provide an air diffusion device in which water to be treated is caused to flow into an air diffusion pipe, thereby allowing closing of the air diffusion holes to be suppressed and sediment to be easily removed in the branch pipe as well as an air diffusion method and water treatment device in which this air diffusion device is used.

Abstract: A hollow fiber membrane module in which a housing body forming the hollow fiber membrane module includes an insertion opening into which end parts of the plurality of hollow fiber membranes are inserted so as to be fixed and held, and an opening portion which exposes open end surfaces of a plurality of hollow fiber membranes inserted from the insertion opening to outside, and a cover that blocks the opening portion of the housing body. According to the present invention, it is possible to provide a housing enabling open end surfaces of hollow fiber membranes to be sealed by easily exposing the open end surfaces of the hollow fiber membranes when the hollow fiber membranes are damaged.