Air Filter Performance Indicators

Filtering accuracy
The maximum diameter of impurity particles allowed to pass through. The key to affecting filtration accuracy is the filter element. Different filter elements can be selected according to the needs of subsequent components to achieve the corresponding filtration accuracy.
Flow characteristics
It refers to the relationship curve between the air flow rate through the filter and the pressure drop at both ends of the filter under a certain inlet pressure. In actual use, it is best to choose within the range of pressure loss less than 0.03MPa. In air filters, the main factors affecting flow characteristics are the body and filter element.
Water splitting efficiency
The ratio of separated moisture to the moisture content in the air at the inlet. It is generally required that the water separation efficiency of the air filter be not less than 80%. The main factor affecting the water separation efficiency is the guide plate.
Air filters have different filtration efficiencies when measured with different concentrations.
(1) Weight efficiency dust concentration in mass concentration (g/m) ³) To represent
(2) The counting efficiency of dust concentration is expressed in counting concentration (pc/L)
(3) The sodium flame efficiency uses solid sodium chloride particles as the dust source. Measure the concentration of sodium chloride particles using a photoelectric flame photometer. The sodium flame efficiency is equivalent to the counting efficiency.
Filter resistance
The resistance of a new filter at the rated air volume is called the initial resistance; The resistance when the dust capacity of the filter reaches a sufficient level at the rated air volume and requires cleaning or replacement of the filter material is called the final resistance.
The dust capacity of the filter
When the resistance of the filter reaches the final resistance at the rated air volume, the total mass of dust particles it accommodates is called the dust capacity of the filter.
Selection principle
Reasonably select the appropriate air filter based on the specific situation, and the selection principles are as follows:
1. Determine the efficiency of the final stage air filter according to the indoor cleanliness and purification standards, and reasonably select the combination level and efficiency of each stage of the air filter. If general purification is required indoors, initial efficiency filters can be used; If moderate purification is required indoors, two-stage filters with initial and intermediate efficiency should be used; If ultra clean purification is required indoors, primary, medium, and high efficiency three-level purification filtration should be used, and the efficiency of each level of filter should be reasonably and properly matched. If the efficiency difference between adjacent two levels of filters is too large, the previous level of filter cannot protect the subsequent level of filter.
2. Correctly measure the dust content and particle characteristics of outdoor air. Because filters filter and purify outdoor air before sending it indoors, the dust content of outdoor air is a very important data. Especially in multi-stage purification and filtration treatment, when selecting a pre filter, factors such as usage environment, spare parts cost, operating energy consumption, maintenance and supply should be comprehensively considered before making a decision.
3. Correctly determine filter characteristics. The characteristics of filters mainly include filtration efficiency, resistance, penetration rate, dust capacity, filtration wind speed, and processing air volume. If conditions permit, high-efficiency, low resistance, large dust capacity, moderate filtering wind speed, large processing air volume, convenient manufacturing and installation, and low price filters should be selected as much as possible. This is an economic analysis that comprehensively considers one-time investment, secondary investment, and energy efficiency ratio when selecting air filters.
4. Analyze the properties of dusty gases. The properties of dusty gases related to the selection of air filters mainly include temperature, humidity, acidity, alkalinity, and the amount of organic solvents. Because some filters allow use at high temperatures, while others can only operate at room temperature and normal humidity, and the amount of acid, alkali, and organic solvents in dusty gases can affect the performance and efficiency of air filters.