Fine filtration equipment (also known as security filters) mostly use stainless steel as the outer shell, with internal filter elements (such as PP cotton). It is mainly used after multi medium pre-treatment filtration and before membrane filtration equipment such as reverse osmosis and ultrafiltration. Used to filter out fine substances (such as fine quartz sand, activated carbon particles, etc.) that have been filtered through multiple media, to ensure water quality filtration accuracy and maintain membrane filtration components from being damaged by large particulate matter. The precision level of the filter element installed in the fine filtration equipment can be divided into 0.5 μ s. 1 μ s. 5 μ s. 10 μ According to different application scenarios, different filtration accuracies are selected to ensure the accuracy of the effluent. Different raw materials such as PP cotton, nylon, and melt blown are used as filter elements to remove small suspended solids and other impurities in the water, ensuring that the raw water quality meets the inlet requirements of the reverse osmosis membrane.

Process principle

The security filter belongs to the fine filter category, and its working principle is to use PP filter element 5 μ Perform mechanical filtration on the pores of m. The trace suspended particles, colloids, microorganisms, etc. remaining in the water are intercepted or adsorbed on the surface and pores of the filter element. As the water production time increases, the operating resistance of the filter element gradually increases due to the pollution of intercepted substances. When the water pressure difference between the inlet and outlet reaches 0.1MPa, the filter element should be replaced. The primary advantages of security filters are high efficiency, low resistance, and easy replacement.

Structure and principle

The fine filter uses formed filter materials, which, under the action of pressure, allow the original liquid to pass through the filter material, leaving the filter residue on the pipe wall, and the filtrate flows out through the filter material to achieve the purpose of filtration. Structure: filter cloth, filter screen, filter plate, sintered filter tube, wire wound filter element, melt blown filter element, etc. Due to different filter materials, the filter aperture is also different. Fine filtration is a type of filtration that lies between sand filtration (coarse filtration) and ultrafiltration, with a filter aperture generally ranging from 0.5 to 120 μ M scale. The same form of filter material can be divided into different specifications according to its external dimensions.

There are two types of wire wound filter elements (also known as honeycomb filter elements):

One type is polypropylene fiber - polypropylene skeleton filter element, which should not be used at temperatures exceeding 60 ℃;

Another type is degreased cotton fiber - stainless steel skeleton filter element, which should not be used at temperatures exceeding 120 ℃. The melt blown filter element is made of polypropylene as the raw material and uses a filter material formed by the melt blown process, with a working temperature not exceeding 60 ℃. Fine filtration can remove suspended solids, certain colloidal substances, and small particles from water.

maintenance

(1) The water source is generally a fixed source and cannot be easily changed.

(2) Strengthen the operation of pre-treatment, optimize the dosage of flocculants and coagulants, select appropriate scale inhibitors from water sources, adjust various pre-treatment equipment to optimal operating conditions, strictly follow the requirements of operating procedures, and ensure that the quality of pre-treatment effluent is qualified.

(3) Choosing high-quality brand filter elements can not only extend the service life of the filter element, but also ensure the quality of the outlet water of the security filter.

For micron level filtration, the inner core is the inner layer of filtration. The inner core is a hot melt bonded structure with integrity, downstream cleanliness, and rigidity, and does not require a support core. Similarly, the adhesive surface coating with permeability * is very smooth and can avoid loose fiber movement, which is crucial for use with high purity requirements.