Cleaning system and method for ultrafiltration membrane

Abstract

The invention belongs to the technical field of ultrafiltration membrane cleaning, and discloses an ultrafiltration membrane cleaning system and method. The system comprises a raw water tank, an ultrafiltration water inlet pump, a self-cleaning filter, ultrafiltration equipment, a water producing tank, a tail gas destroying device, a backwashing water pump, an air compressor subsystem, an ozone generator subsystem and an optional dosing cleaning subsystem. By using the novel ultrafiltration membrane system in cooperation with the ozone pre-oxidation method, the service life of the ultrafiltration membrane can be prolonged, the cleaning effect is improved, and the influence on the online rate of membrane operation is reduced.

Description

technical field [0001] The invention belongs to the technical field of ultrafiltration membrane cleaning, and more particularly, relates to a cleaning system and method for an ultrafiltration membrane. Background technique [0002] Membrane fouling refers to the reduction of membrane pore size due to the adsorption and deposition of particles, colloidal particles or solute macromolecules in water and the membrane due to physical and chemical interaction or mechanical action during the membrane filtration process on the membrane surface or in the membrane pores. Blockage causes irreversible changes in the permeate flow and separation characteristics of the membrane. In the field of water treatment, ultrafiltration membranes are inevitably polluted during normal operation, which is also an insurmountable problem that restricts the normal water production of membranes. [0003] At present, the common methods for the prevention and control of membrane fouling are physical clean...

AI Technical Summary

Problems solved by technology

NIPS membrane has disadvantages such as relatively poor chemical stability and low mechanical strength, while TIPS membrane has a certain improvement in mechanical strength compared with NIPS membrane, but still has the problems of relatively poor chemical stability and hydrophilicity.

The above factors make the PVDF membrane prone to degradation of filtration performance or broken wires caused by membrane corrosion under conventional membrane cleaning methods, resulting in a reduction in the overall service life of the membrane.

[0006] (2) Incomplete cleaning: Whether it is physical cleaning or chemical cleaning, in essence, after the membrane pollution reaches a certain level, restorative cleaning is performed, and as the service life increases, the water production performance of the ultrafiltration membrane will decrease year by year. This also shows that conventional physical or chemical cleaning cannot completely remove the contamination of the membrane, and there are cases where the cleaning is not thorough

[0007] (3) Cleaning leads to low online rate of ultrafiltration membrane operation: during the operation of the ultrafiltration system, after a period of continuous water production, backwashing or chemical cleaning is required to ensure that the water flux of the membrane is maintained within the design range, while Frequent backwashing or chemical cleaning will reduce the water production time of the membrane system and reduce the overall online rate of the membrane system

[0008] Therefore, in view of the problems of incomplete cleaning, affecting the online rate of membrane operation, and even reducing the life of the membrane in the current ultrafiltration membrane cleaning technology, it is urgent to propose a new system and method for ultrafiltration membrane cleaning.

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