Pore diffusion type flat membrane separating apparatus

A pore diffusion type flat membrane separation apparatus comprising:

• a plurality of flat membranes;
• and
• a plurality of flat plate-like supports arranged alternately with the plurality of flat membranes,
• each flat membrane defining a plurality of pores and separating a predetermined dispersed substance contained in a solution by a pore diffusion technique where substantially no transmembrane pressure difference is applied, and
• each flat plate-like support having a flow conduit on one or both faces thereof, wherein
• an average pore diameter of each flat membrane is set from 5 nm to 500 nm, and a porosity of each flat membrane is set from 0.6 to 0.9;
• a ratio between a spatial volume of any flow conduit and a membrane area of a corresponding flat membrane is set from 0.04 to 0.4 cm;
• each flat plate-like support includes, in at least two positions in lateral faces thereof, water conduits in communication with a flow conduit, so that flow directions of said solution in flow conduits of upper and lower flat plate-like supports separated by a flat membrane may be substantially in the same direction;
• a treatment liquid subjected to a diffusion treatment is caused to flow under a flat membrane and a diffusion liquid in which a dispersed substance flows is caused to flow on and upwardly of a flat membrane;
• an outer side flat plate-like support includes a flow conduit in one face thereof, a water conduit on an inlet side, and a water conduit on an outlet side both in communication with a flow conduit in a lateral face of the outer side flat plate-like support;
• at least one intermediate flat plate-like support includes flow conduits in both faces thereof,
• the flow conduit in one face being in communication with an inlet side water conduit where treatment liquid flows in and an outlet side water conduit where the treatment liquid flows out,
• the flow conduit in the other face being in communication with an inlet side water conduit where the diffusion liquid flows in and outlet side water conduit where the diffusion liquid flows out, and
• the treatment liquid-inlet side water conduit, the treatment liquid-outlet side water conduit, the diffusion liquid-inlet side water conduit, and the diffusion liquid-outlet side water conduit being provided in the lateral face of the at least one intermediate flat plate-like support;
• and
• said plurality of flat plate-like supports and said plurality of flat membranes can be assembled with and disassembled from each other.