초록 ▼

A method of cleaning a membrane in a membrane separation activated-sludge process. By the method, deposits adherent to the surface of a membrane used in a membrane separation activated-sludge process can be effectively scratched off and the membrane filtration rate can be prevented from decreasing.

A method of cleaning a membrane in a membrane separation activated-sludge process. By the method, deposits adherent to the surface of a membrane used in a membrane separation activated-sludge process can be effectively scratched off and the membrane filtration rate can be prevented from decreasing. Membrane-cleaning particles (4) in which the surface to be in contact with the water to be treated has been hydrophilized and has a surface roughness of 100-2,500 μm are introduced into a bioreactor (1). The particles are caused to flow by the lifting effect of air bubbles ejected from an aerator (3) or by the fluidizing effect of a fluidizing means to thereby cause the particles to scratch off deposits adherent to the surface of a separation membrane element (2). In one embodiment, membrane-cleaning particles (4) which are non-porous or have closed cells are used. In another embodiment, membrane-cleaning particles (4) having an antibacterial ingredient, such as copper or silver, supported on the surface or in inner parts thereof are used. In a still another embodiment, the membrane-cleaning particles (4) are periodically brought into an anaerobic condition to remove microorganisms from the particle surface.

대표청구항 ▼

The invention claimed is: 1. A method for cleaning a membrane in a membrane bioreactor process, comprising introducing a membrane-cleaning particle, in which a surface that makes contact with water to be treated is hydrophilized, and in which asperities of a surface that makes contact with a separa

The invention claimed is: 1. A method for cleaning a membrane in a membrane bioreactor process, comprising introducing a membrane-cleaning particle, in which a surface that makes contact with water to be treated is hydrophilized, and in which asperities of a surface that makes contact with a separation membrane element, are not less than 100 μm and not more than 2500 μm, into a biological reaction tank with a separation membrane element submersed therein, and by causing the membrane-cleaning particle to flow by means of air-lifting effects of bubbles ejected from an air diffuser, or by the effects of a fluidizing means, so as to scrape off deposits adherent to a surface of the separation membrane element. 2. The method for cleaning a membrane in a membrane bioreactor process according to claim 1, wherein a membrane-cleaning particle that consists of a non-pore, or of a closed pore material, is used. 3. The method for cleaning a membrane in a membrane bioreactor process according to claim 1, wherein a membrane-cleaning particle that carries an antibacterial component is used. 4. The method for cleaning a membrane in a membrane bioreactor process according to claim 3, wherein the antibacterial component is either silver or copper. 5. The method for cleaning a membrane in a membrane bioreactor process according to claim 1, wherein the membrane-cleaning particle is periodically brought into an anaerobic condition so to peel off a microbe on a surface of the particle.