What is the formula for calculating the filtration efficiency of a filter
The filtration efficiency of a filter is usually calculated using the following formula:
Efficiency=(1- (concentration decrease rate 2/concentration decrease rate 1) x 100%
Among them, concentration reduction rate 1 represents the rate of decrease in particle concentration before the filter, while concentration reduction rate 2 represents the rate of decrease in particle concentration after the filter Rate.
This calculation method is based on the concentration changes of particulate matter, and evaluates the filtering effect of the filter by measuring the concentration decrease of particulate matter before and after the filter. A higher filtration efficiency means that the filter can more effectively remove particulate matter and provide cleaner air.
It should be noted that the filtration efficiency of a filter may be affected by various factors, including filter type, design, material, and particle size and concentration. Therefore, in practical applications, different methods and standards may be used to evaluate and report the filtering efficiency of filters. The specific calculation methods and standards may vary depending on different industries and applications.
The formula for calculating the filtration efficiency of a filter can be used using the following commonly used calculation methods
1. Particle Counting Method:
This method calculates the filtration efficiency of the filter by measuring the number of particles in the air before and after entering and leaving the filter. The calculation formula is as follows:
Filtering efficiency=(number of particles in the air before entering the filter - number of particles in the air after passing through the filter)/number of particles in the air before entering the filter.
2. According to the Mass Based Method:
This method calculates the filtration efficiency of the filter by measuring the particle mass before and after entering and leaving the filter. The
calculation formula is as follows:
Filtering efficiency=(mass of particles in the air before entering the filter - mass of particles in the air after passing through the filter)/mass of particles in the air before entering the filter.
3. A comprehensive method combining Particle Counting Method and Mass Based Method:
This method combines particle counting and mass based methods, and calculates the filtration efficiency of the filter by simultaneously measuring the number and mass of particles in the air before and after entering and leaving the filter.
The above are commonly used methods for calculating the filtering efficiency of filters. Depending on the actual situation and needs, a suitable method can be selected for calculation. Please note that different types and specifications of filters may require different calculation methods. Please refer to relevant standards and specifications for specific calculations.
