What is the performance index of the air filter?
At present, the application of air filters in air conditioning and ventilation systems is increasing, and the service life is one of the indicators that people care about when choosing an air filter. However, it is difficult to predict the service life of the air filter in practice, so it is usually evaluated by the dust holding capacity.
The dust holding capacity can only qualitatively but not quantitatively reflect the actual weight of the dust contained in the air filter. At the same time, only when the test conditions and methods are the same, the life of different filters can be evaluated according to the dust holding capacity data.
Due to various reasons, in the past ten years, all professional laboratories and filter manufacturers in the country seldom conduct tests on dust holding capacity. At present, the industry standard JG/T22-1999 “Performance Test Method of Air Filters for General Ventilation” is being revised, and the dust holding capacity test method is one of the key contents of the revision. In this paper, the definition of dust holding capacity is defined by four representative standards in air filter performance test methods, including JG/T22-1999, American ANSI/ASHRAE52.1-1992, European EN779: 2002, and Japanese JIS B9908: 2001. Introduce and compare and analyze the test method to help the revision of the national standard.
Introduction of Dust Holding Capacity in National Standards
In JG/T22-1999, the definition of dust holding capacity is: the total amount of artificial dust intercepted by the tested filter before reaching the termination condition of the test, which is multiplied by the total dust mass of the artificial dust multiplied by the average of the tested filter. The weight efficiency is calculated; the test method of dust holding capacity is: send a certain amount of artificial dust to the standard test air duct equipped with the tested filter and the end filter (usually high-efficiency filter) through the dust generating device, until After the artificial dust is sent, remove the test filter and the end filter, and weigh them respectively to obtain their mass change, so as to calculate the weighing efficiency of the test filter, and repeat the above steps until the test filter reaches the final stage. The resistance value, and then the average weight efficiency of the whole test process is obtained, and finally the dust holding capacity of the tested filter is obtained by multiplying the average weight efficiency by the total dust generation.
The definition of dust holding capacity and the test method of dust holding capacity in EN779:2002 are almost the same as those in JG/T22-1999, while ANSI/ASHRAE52.1-1992 is only similar to JG/T22-1999 in terms of the termination conditions of dust holding capacity test. The difference, other content is the same; and JIS B9908: 2001 is similar to JG/T22-1999 except the termination conditions and calculation methods of dust holding capacity test are not the same. Therefore, the dust holding capacity test methods of each standard are mainly due to some differences in the test termination conditions and calculation methods.