VARIABLE-POROSITY SUBSTRATE AND MEMBRANE FOR TANGENTIAL FILTRATION OF LIQUID MEDIUM FLOW Russian patent published in 2010 - IPC B01D63/06 

FIELD: process engineering.

SUBSTANCE: invention relates to tangential separation and can be used for extraction and concentration. Porous substrate (1) for tangential treatment of liquid medium has, at least, one surface (3) that faces said treated medium and surface (1_l) wherefrom fraction escapes, said fraction being called a filtrate resulted from clogging of initial substrate by inorganic particles. Note here that said surface (1) has crosswise porosity extending to preset constant depth (e) from surface (3) and increasing as it extends deeper into substrate (1) in direction perpendicular to surface (3). Proposed invention covers also membrane intended for tangential filtration wherein said porous substrate is jointed with, at least one separating layer, and method to produced above described porous substrate.

EFFECT: reduced permeability of porous substrate compared with that of starting substrate.

21 cl, 4 dwg