TUBULAR MEMBRANE SEPARATION DEVICE WITH CROSSED TUBES

摘要

A fluid treatment apparatus comprising a receptacle and accomodated therein a multi-layered structure assembly composed of hollow filaments. The assembly consists of at least one multi-layered structure, and in the multi-layered structure, the filament orienting direction in a given layer intersects with that in a layer adjacent thereto at an angle of 10 to 90 degrees. The hollow filament used in the assembly can be produced, for example, by deacetylating hollow cellulose acetate filaments with a 0.25-10% by weight aqueous solution of sodium hydroxide or potassium hydroxide at a temperature of 65 to 100.degree.C. The fluid treatment apparatus can be used for various separating operations for fluid mixtures, and its especially useful application is found in artificial kidneys.