SEPARATION MEMBRANE UNIT ARRANGING MIXING ACCELERATING MEANS OF FLUID ON MEMBRANE SURFACE

PROBLEM TO BE SOLVED: To provide a separation membrane unit and a membrane separator arranging a mixing accelerating means of fluid on membrane surface which lessens concentration polarization on the supply side (primary side) of the separation membrane such as pervaporation membrane and improves a permeation performance of the membrane. SOLUTION: In this separation membrane unit 10, first fluid L is supplied to the primary side of the separation membrane 11a having fine pores of molecular level, the secondary side of the separation membrane 11a is evacuated or second fluid G is supplied to the secondary side thereof and substances mixed into the first fluid L is selectively extracted to the secondary side. Therein, in the vicinity of membrane surface or on the membrane surface of the primary side of the separation membrane 11a, a mixing accelerating means of fluid which mixes the fluid L inside and outside the boundary layer of the first fluid L is arranged.