Abstract: Disclosed is a diffuser installation structure capable of improving uniformity of air bubbles discharged from air bubble discharge holes, restricting the formation of dead zone air bubble discharge holes, and having the tolerance against design deviation. In the installation structure for a diffuser including at least one air feeding port and an air bubble discharge wall having a plurality of air bubble discharge holes, the air bubble discharge wall is inclined upward in the direction of increasing distance relative to the air feeding port.

Abstract: Disclosed is a diffuser installation structure capable of improving uniformity of air bubbles discharged from air bubble discharge holes, restricting the formation of dead zone air bubble discharge holes, and having the tolerance against design deviation. In the installation structure for a diffuser comprising at least one air feeding port and an air bubble discharge wall having a plurality of air bubble discharge holes, the air bubble discharge wall is inclined upward in the direction of increasing distance relative to the air feeding port.

Abstract: Disclosed is a diffuser installation structure capable of improving uniformity of air bubbles discharged from air bubble discharge holes, restricting the formation of dead zone air bubble discharge holes, and having the tolerance against design deviation. In the installation structure for a diffuser comprising at least one air feeding port and an air bubble discharge wall having a plurality of air bubble discharge holes, the air bubble discharge wall is inclined upward in the direction of increasing distance relative to the air feeding port.

Abstract: Disclosed is a diffuser installation structure capable of improving uniformity of air bubbles discharged from air bubble discharge holes, restricting the formation of dead zone air bubble discharge holes, and having the tolerance against design deviation. In the installation structure for a diffuser including at least one air feeding port and an air bubble discharge wall having a plurality of air bubble discharge holes, the air bubble discharge wall is inclined upward in the direction of increasing distance relative to the air feeding port.

Abstract: Disclosed is a cartridge module of hollow fiber membranes, which can be easily mounted on and dismounted from a module mounting frame, and allow a process for removal of the inter-membrane clogging to be performed in an effective and simple manner. The cartridge module is mainly characterized in that a water collecting header has an opened first collected water outlet, which is located at the upper portion of the front surface of the water collecting header and can be opened and closed; and a closed second collected water outlet, which is located at the lower portion of the front surface of the water collecting header and can be opened and closed. The inter-membrane clogging can be very simply removed by dismounting, turning upside down, and remounting the cartridge module.

Abstract: Disclosed is a cartridge module of hollow fiber membranes, which can be easily mounted on and dismounted from a module mounting frame, and allow a process for removal of the inter-membrane clogging to be performed in an effective and simple manner. The cartridge module is mainly characterized in that a water collecting header has an opened first collected water outlet, which is located at the upper portion of the front surface of the water collecting header and can be opened and closed; and a closed second collected water outlet, which is located at the lower portion of the front surface of the water collecting header and can be opened and closed. The inter-membrane clogging can be very simply removed by dismounting, turning upside down, and remounting the cartridge module.

Abstract: Disclosed is a diffuser installation structure capable of improving uniformity of air bubbles discharged from air bubble discharge holes, restricting the formation of dead zone air bubble discharge holes, and having the tolerance against design deviation. In the installation structure for a diffuser comprising at least one air feeding port and an air bubble discharge wall having a plurality of air bubble discharge holes, the air bubble discharge wall is inclined upward in the direction of increasing distance relative to the air feeding port.

Abstract: A porous polyethylene hollow fiber membrane having a pore-size gradient across the inner and outer surfaces thereof is prepared by introducing, during the cooling step of a melt-spun polyethylene hollow fiber, a nitrogen flow and a solvent having a boiling point in the range of 30 to 80° C. to the inner and outer surfaces of the melt-spun hollow fiber, respectively.