Applications of washable, high-flow filter cartridges-Hezhong Environment (Beijing) Co., Ltd. was established in 2003

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Applications of washable, high-flow filter cartridges

Published Time:

2021-10-29

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Application of Backwashable High-Flow Filters

In systems using reverse osmosis membranes for pretreatment, to ensure the normal operation of the reverse osmosis components and reduce the operational risks of the reverse osmosis system, an inlet security filter is usually installed before the reverse osmosis components. The security filter contains filter cartridges. Under pressure, the raw liquid passes through the filter cartridge, contaminants are intercepted by the filter cartridge, and the filtrate flows out through the filter material, thus achieving the purpose of filtration.

Location of the Security Filter in the System

The essence of filter cartridge filtration is a kind of sieving. The filter cartridge can directly intercept contaminants larger than its pore size, and some small-particle contaminants will also be intercepted by bridging, thus achieving the filtration effect.

Interception Filtration

As the intercepted contaminants increase, the filter cartridge's flow area decreases, the filter cartridge's water output decreases, and the pressure difference between the filter cartridge inlet and outlet increases. When the filter cartridge pressure difference reaches the replacement value, the filter cartridge needs to be replaced. Otherwise, the low water output will have an adverse effect on the reverse osmosis high-pressure pump, and the high pressure difference may damage the filter cartridge, adversely affecting the system operation. Colloids, particles, and microorganisms in the water will all cause clogging of the filter cartridge.

Microstructure of the Filter Material

From the microstructure of the filter material, we can see that the filter cartridge relies on countless "flow channels" formed by fibers for filtration. Contaminants with a particle size larger than the diameter of the flow channel are intercepted, and as the contaminants accumulating in the flow channel increase, the channel is eventually "blocked".

Clogging of the Filter Cartridge

Currently, most high-flow filter cartridges on the market are disposable. When the filter cartridge clogs and the pressure difference increases to the replacement pressure difference, only a new filter cartridge can be replaced, and the old filter cartridge is discarded. For users, the purchase and replacement costs of filter cartridges are unavoidable expenses during the use process. With the increasing emphasis on environmental protection by society and environmental protection departments, the disposal of used filter cartridges has also become another problem for users during the use process. Therefore, the market urgently needs a filtration product with a longer service life to reduce the replacement frequency and the amount of used filter cartridges to be processed.

To solve this problem, some users adopt the method of disassembling, cleaning, and soaking the old filter cartridges in medicine for reuse. Although this method is simple to operate, the accuracy of the filter material after cleaning and soaking cannot be guaranteed, and the structural strength of the filter cartridge after use and disassembly cannot be guaranteed. Therefore, this operation method greatly increases the risk of system operation.

Some manufacturers have promoted the following two schemes, but due to the limitations and drawbacks of the schemes, they have not been able to meet market demand.

Ceramic and Metal Powder Sintered Filter Cartridge Scheme

This scheme's filter cartridge backwashing is simple and easy to operate, but the filter cartridge has low flow rate and a narrow accuracy range. In actual use, it will cause high investment costs and few accuracy options.

Backwashing Scheme for Ordinary High-Flow Filter Cartridges

This scheme involves directly backwashing ordinary high-flow filter cartridges, which can lead to damage of the folded structure of the filter cartridge, incomplete cleaning of the filter cartridge, and changes in the accuracy of the filter material.

Our company's R&D and technical department, after extensive research and experiments to overcome various technical difficulties, has made technical improvements and innovations to the filter material, skeleton, and folding method based on ordinary high-flow filter cartridges, and finally determined a backwashable high-flow filter cartridge scheme that meets user needs.

Using Ultrafine Fibers Increased Flow Rate and Filter Material Accuracy Guarantee

Our company's backwashable filter cartridge filter material is made of high-strength ultrafine fibers by melt blowing, increasing the porosity and effective filtration area of the filter material, improving the accuracy retention of the filter material, and avoiding the phenomenon of penetration and unloading after backwashing of the filter material.

Progressive Filtration Method

Progressive filtration method, graded filtration, large particles are intercepted on the outermost side of the filter material, improving the backwashing ability of the filter material, and avoiding the concentration of all contaminants in the filter material, resulting in insufficient backwashing force and incomplete backwashing.

Using Compressed Air to Enhance Cleaning Effect

The backwashing filter is equipped with a compressed air supply port. During the backwashing process, "air scrubbing" is performed, and the filter material is "shaken" and "air burst" to accelerate the cleaning and discharge of contaminants.

Bidirectional Flow Inner and Outer Skeleton

The inner and outer parts of the filter cartridge use a high-strength PP support skeleton. The skeleton openings and ribs use a special structure and combination, resulting in better fluid performance and bidirectional flow for both filtration and backwashing, enhancing the backwashing ability of the filter cartridge.

Special Folding Structure

Due to the cylindrical structure of the filter cartridge, the outer side of the folded filter cartridge is inevitably loose, and the inner side is tight. Direct backwashing is very likely to damage the folded structure. Our company's backwashable filter cartridge uses a special "outer expansion" folding structure to enhance the tightness of the outer side of the filter cartridge and avoid the "loosening" phenomenon of the outer side of the filter cartridge due to backwashing.

Backwashing Filter Cartridge Pilot System

After numerous laboratory, factory tests, and on-site pilot tests, the results show that our company's backwashable high-flow filter cartridges have a significant effect, significantly improving the service life of the filter cartridges, greatly shortening the replacement frequency of the filter cartridges, and greatly saving on-site maintenance and replacement costs and the cost of disposing of discarded filter cartridges.

Source: Hezhong Technical Department