How is the absorbent cotton filter element applied to the purification treatment of industrial wastewater?

In the purification of industrial wastewater, absorbent cotton filter element mainly filters impurities through physical interception, which is usually used as the core component of pretreatment or deep filtration, and adapts to different filtering equipment to realize purification.

I. Core application principles

The filtration process of absorbent cotton filter element is based on the "deep filtration" mechanism, which is divided into two steps:

Preliminary interception: When wastewater flows through the filter element, larger suspended solids (such as sediment and debris) are blocked by fiber gaps on the surface of the filter element, forming a preliminary filter cake.

Fine filtration: the subsequent water flows into the filter element, and fine colloidal particles and tiny organic matter are entangled and adsorbed by the loose fiber network, and finally solid-liquid separation is realized, and the purified water is discharged from the filter element outlet.

Second, the typical application process and equipment

Absorbent cotton filter elements need to be used with specific equipment, and common application processes can be divided into pretreatment and deep filtration:

1. As a pretreatment link (to protect the subsequent equipment)

Application scenario: When the wastewater contains a lot of suspended solids, it should be filtered with absorbent cotton filter element to avoid the blockage of subsequent precision equipment (such as reverse osmosis membrane and ion exchange resin).

Common equipment: bag filter, filter element filter.

Operating steps:

Put the absorbent cotton filter element into the filter cartridge or filter bag of the filter and check the sealing condition.

Start the waste water pump, so that the waste water can slowly enter the filter at low pressure (usually 0.1-0.3MPa), so as to prevent the filter element from being washed away by excessive pressure.

Regularly monitor the pressure difference between inlet and outlet water. When the pressure difference exceeds 0.1MPa, replace the absorbent cotton filter element with a new one.

2. As a step of advanced filtration (improving effluent quality)

Application scenario: Treating low-concentration suspended solids wastewater (such as food processing wastewater and mechanical cooling wastewater), and directly using absorbent cotton filter element to achieve up-to-standard discharge or reuse.

Common equipment: small multi-connected filter element filter, negative pressure filter device.

Operation features: 2-3 absorbent cotton filter elements can be connected in series to gradually improve the filtration accuracy; In some scenes, a filter screen will be added in front of the filter element to intercept large particles first and extend the life of the filter element.

Three, the key points for attention in the application

Pretreatment of waste water: If the waste water contains grease or viscous impurities, it needs to be pretreated by grease trap, grille, etc. to prevent grease from adhering to absorbent cotton fibers, which will lead to rapid failure of the filter element.

PH value control: only used for neutral wastewater (pH 6-8). If the wastewater is acidic or alkaline, the pH value should be adjusted first, and then filtered in absorbent cotton filter element to prevent the filter element from being corroded.

Replacement cycle: according to the concentration of suspended solids in wastewater, the low-concentration wastewater can be used for 1-3 days, and the high-concentration wastewater may need to be replaced every day to avoid the reduction of filtration efficiency or excessive pressure of equipment caused by blockage.