Panel filter In china Blog
Air filter for air-conditioning system-Mar.18.2015
Generally speaking, in the clean room, in order to ensure the dust control level of cleanliness within the required number of particles, three or four air filters are used in the purification of air-conditioning system, to blockthe clean room (plant) dust particles in the air.
Air filter used in air conditioning systems,according to the efficiency divided into four types, pre filter, medium filter, HEPA filter(some recorded in the cleanliness of the room 100, such as 10 clean room, also need ULPA filter).
Prefilter was mainly targeted at more than 10um dust, the counting efficiency (for 0.3um dust particles) is less than 20%, air resistance is less than 30Pa. Medium filters in filter object is 1 ~ 10um dust particles, the counting efficiency (for 0.3um dust particles) is 20% to 90%, air resistance is less than 100Pa.Sub-HEPA filters filter out the main object is less than 5um dust particles, the counting efficiency (for 0.3um dust particles) of 90% to 99.9%, the air resistance is less than 150pa.
HEPA filters mainly for equipment dust particles smaller than 1.0um, the counting efficiency (for 0.3um particle size of dust particles) is greater than 99.97%, the air resistance is less than 250Pa.
Air filters, used in air conditioning systems, combined selected according to the rated air filter at all levels, the amount of air resistance and filtration efficiency before design of system.At the same time, the size of pre-filters and medium filter is determined based on filtered air flow and the filtration rate of filtering media. The filtration rate of pre-filter is 0.4 ~ 1.2m / s, medium filter is 0.2 ~ 0.4m / s, HEPA filters ia 0.01 ~ 0.03m / s.
Pre-filter,medium filter, HEPA filters are combined, generally used for class100000-1000000 of the clean room. For lclass10000-100 of the cleanroom, the purification air-conditioning system also used pre-filters, medium filters, medium filters andHEPA filters,four air filter combinations, or early in sub-high efficiency air filter, HEPA filters,four filter combinations.
In the four air filter combination, the increase in the third grade or sub-high efficiency air filters designed to purify the air conditioning system to improve the cleanliness of the air supply, to extend the end of the air filter life, reducing its replacement times.