Flexible tubular large-aperture membrane filtration device and cleaning method thereof

Abstract

The invention discloses a flexible tubular large-aperture membrane filtration device and a cleaning method thereof. According to the invention, the diameter of a tubular membrane in the membrane filtration device is not less than 5 mm; the aperture of the tubular membrane is 6-200 [mu]m; the tubular membrane is made of a homogeneous membrane, so forward and reverse cleaning and filtering effects are the same; the tubular membrane has sufficient flexibility for physical deformation; and gas in a gas source can enter the membrane filtration device through an opened water production side gas inlet valve and an opened water inlet side bottom gas inlet valve respectively and then is discharged through a water production side gas outlet valve, and no gas seal is formed under the condition of weak pressure regardless of hydrophilic, hydrophobic or humid conditions. Traditional water cleaning is replaced by gas cleaning in the invention, cleaning is completed by means of gas such as air, dirt and the like which are hidden on the inner wall of the membrane filtration device and are difficult to clean are effectively removed, cleaning is more thorough, and water consumption is reduced; the filtering effect is not affected by water flux, so yield is high; cleaning does not depend on chemical reagents, so reagent residues do not exist, and use safety is high; and the cleaning method is simple, efficient, energy-saving and consumption-reducing.

Description

technical field [0001] The invention belongs to the technical field of membrane filtration device cleaning methods, and in particular relates to a flexible tube type large-aperture membrane filtration device and a cleaning method thereof. Background technique [0002] Membrane fouling is a common problem that plagues all membrane filtration devices (including: microfiltration, ultrafiltration, nanofiltration, and reverse osmosis). Membrane fouling usually refers to the physical and chemical interaction between particles, colloidal particles, macromolecular organics, and dissolved substances in the liquid during the process of membrane filtration. The membrane pores become smaller or clogged, which leads to a decrease in the productivity or separation efficiency of the membrane. [0003] Usually, in the use of membrane filtration devices, when the water production rate or water quality is significantly reduced, membrane cleaning is required. Such cleaning includes physical ...

AI Technical Summary

Problems solved by technology

Usually, the flux of membrane filtration, taking UF as an example, is 50-80LMH, and the flux of backwash is generally around 100-120LMH, but backwashing at low flow rate cannot effectively remove the intercepted substances on the surface of the membrane or in the pore diameter. incomplete cleaning

And usually after a certain number of backwashing, it is necessary to use more drastic methods such as chemical cleaning to solve the problem of membrane fouling. Frequent physical and chemical cleaning will reduce the service life of the membrane.

The traditional liquid cleaning method is limited by the liquid flow equipment (pump), and it is difficult to achieve a high limit flux in a short period of time. It also needs to use a large amount of produced water or purified water, which reduces the yield

Images