Filtration device and filtration method using same

#The present invention relates to a filtration device and a filtration method using the same.

#As a solid-liquid separator for sewage treatment or the like, a filtration device having a filtration module formed by a bundle of hollow fiber membranes has been used. Examples of the filtration device having the filtration module include an external pressure type filtration device in which a solution to be treated is passed to the inner periphery sides of the hollow fiber membranes by raising the pressure on the outer periphery sides of the hollow fiber membranes, an immersion type filtration device in which a solution to be treated is passed to the inner periphery sides by osmotic pressure or negative pressure on the inner periphery sides, and an internal pressure type filtration device in which a solution to be treated is passed to the outer periphery sides of the hollow fiber membranes by raising the pressure on the inner periphery sides of the hollow fiber membranes.

#Of the filtration devices described above, the external pressure type filtration device used is one that includes a tubular body having an inlet and an outlet for a solution to be treated, and a plurality of hollow fiber membranes aligned in the tubular body. In this filtration device, water in the solution to be treated is passed to the inside of the hollow fiber membranes by external pressure, and a filtrated solution is obtained by sucking up the passed water.

#FIG. 1 is a schematic explanatory diagram of a filtration device according to an embodiment of the present invention.

#FIG. 2 is a schematic explanatory diagram illustrating filtration in the filtration device according to the embodiment of the present invention.

#FIG. 3a is a schematic bottom view of a lower holding member included in the filtration module of the filtration device illustrated in FIG. 1.

#A filtration device according to an aspect of the present invention includes a tubular body having an inlet and an outlet for a solution to be treated, and a plurality of hollow fiber membranes aligned in the tubular body. By creating a difference in pressure between the outside and inside of the hollow fiber membranes, water in the solution to be treated is passed from the outside to the inside. The filtration device further includes a gas supply unit configured to supply a bubble from below the plurality of hollow fiber membranes. The tubular body has a gas discharge port above the inlet and the outlet. The gas discharge port is provided for discharging the bubble supplied from the gas supply unit to the outside.

#The filtration device can reduce adhesion of dirt to the surfaces of the hollow fiber membranes by supplying a bubble from the gas supply unit while water in the solution to be treated is passed by creating a difference in pressure between the outside and inside of the hollow fiber membranes (i.e., during filtration). Therefore, the filtration device suffers little degradation in filtration performance caused by adhesion of dirt. Also, since bubbles supplied from the gas supply unit are discharged to the outside through the gas discharge port of the tubular body, the filtration device can suitably perform filtration.

#The filtration device may be of an external pressure type. Thus, the filtration device can be configured by using a basic structure of an external pressure type filtration device that has been conventionally used.