Compressed air drying and purification system composition

Compressed air drying and purification system composition

Since compressed air inevitably contains impurities such as solids, liquids, and gases, and each has its own characteristics, it cannot be achieved with a single device. Therefore, compressed air drying and purification becomes a system, a complete compressed air The drying purification system includes: 1) gas-liquid separator; 2) filter; 3) drying equipment and other facilities.

(1) Gas-water separator

The function of the gas-liquid separator is to pre-treat the compressed air and separate the condensate in the compressed air as 100% as possible. The gas-liquid separator is often installed at the front of the compressed air system.

According to the mechanism of gas-liquid separation, there are often cyclone separators, louvered separators, and vortex separators.

(2) Filter

The filter plays a key role in the compressed air drying and purification system. Using different filters can remove oil (including liquid and gas), solid impurities, microorganisms, harmful gases and other pollutants in the compressed air.

In compressed air drying and purification systems, filters exist everywhere.

In industrial production, filters used in compressed air systems are often divided into categories: oil removal filters, dust removal filters, sterilization filters and special filters.

The oil removal filter is the most widely used filter, and its main function is to remove the oil mist (colloid) in the compressed air. Such as the OIL-X series filter of British domnick hunter company. This type of filter is also called coalescing filter. According to its filtration accuracy (the largest particle diameter that can be effectively intercepted), it can be divided into:

1) Primary/coarse filter: filtration accuracy is less than or equal to 25μm;

2) Fine filter: filtration accuracy is less than or equal to 1μm; residual oil content is 1.0PPm;

3) High-precision filter: filtration accuracy is less than or equal to 0.1μm, and the residual oil content is 0.1ppm;

4) Super filter: The filtration accuracy is less than or equal to 0.01μm, and the residual oil content used in series with the activated carbon filter is ≤0.03ppm.

It should be pointed out that in the performance indicators of this type of filter, residual oil refers to liquid oil, not including gas oil.

Dust filter, strictly speaking, the dust filter and the oil filter are the same type, the difference is that the dust filter is often used at the outlet of the adsorption dryer (see relevant information for details).

The sterilization filter is a sanitary filter, which mainly removes microorganisms in the compressed air. It should be pointed out that the sterilization filter must be processed by the oil removal filter.

Special filter, the most typical special filter is an activated carbon filter, which can filter out certain harmful gases and peculiar smells in the compressed air. It is a chemical filter.

(3) Drying equipment

Drying equipment is equipment to remove water, and the following types are commonly used:

1) Adsorption drying equipment

2) Freeze drying equipment

3) Drying equipment combined with freezing and adsorption

4) Other drying equipment, such as membrane drying, chemical absorption drying, etc.