What are the selection methods of air filter use configuration and various sites?
Reasonable determination of filter efficiency at all levels
In general, the last level of filter determines the degree of air purification, the upstream level of filter only plays a protective role, it protects the downwind filter to extend its service life, or protect the air conditioning system to ensure its normal work.
In the design of air conditioning, the efficiency of the last filter should first be determined according to the user’s clean requirements. Then, the filter that plays a protective role should be selected. If this filter also needs to be protected, the filter should be added at the upwind end of it. The protective filters are collectively referred to as “prefilters”.
The efficiency of each filter level should be properly matched. If the efficiency specifications of the two adjacent stages are too different, the former stage can not protect the latter stage. If the two levels are not different, the burden of the latter level is too small.
The service life of high efficiency filter at the end of clean room should be 5 ~ 15 years, and the most important factor affecting the service life is the quality of the pre-filter. (Shanghai Air Filter manufacturer)
When the “G ~ F ~ H ~ U” efficiency specification is used for classification, the efficiency of the required levels of filters can be easily estimated. In G2 to H12, set a primary filter every 2 to 4 stops. For example, G4→F7→H10, where the terminal H10(sub-high efficiency) filter determines the clean level of air supply, F7 protects H10, and G4 protects F7
High efficiency (HEPA) filter at the end of clean room should be protected by filter with efficiency specification not less than F8; Ultra-high efficiency (ULPA) filter can be used before the F9 ~ H11 air filter. The central air conditioning itself should be protected by filters with efficiency specifications not less than F5.
In areas without sand and low pollution, there is no pre-filter before the F7 filter. G3 ~ F6 is a common primary filter in urban central air conditioning system.
What efficiency level of the pre-filter should be set to protect the latter filter needs to be decided by the designer and the field engineer after considering the operating environment, spare parts cost, operation energy consumption, maintenance cost and other factors. (Shanghai Air Filter manufacturer)
● A class 100 clean room, set F5→F8→H10→H13 four filter, end H13 filter used for 8 years.
● Before the high efficiency filter in a clean room, only F5 filter protection, users should replace the high efficiency filter every year.
● The filter of a fresh air purification system in a heavily polluted city is set to G3→H10, and the H10 filter is scrapped after half a month of system operation.
● A car painting line, filter set to G3→F6→F5. Among them, the end F5 is the filtering material covered with roof, which only plays the role of flow sharing required by the process; F6 determines the purification level of the supply air. The performance of the final filter should be reliable. The efficiency specification of the prefilter should be reasonable. The maintenance of primary filters should be convenient.
Selection of typical site filters
The main filter F5 ~ F7 bag type, no partition plate filter in ordinary central air conditioning has reasonable filtration efficiency, which can protect indoor decoration and air conditioning system
General central air conditioning in the pre-filter G3 ~ F5 A variety of cheap, easy to use filters high dust capacity, supply has guaranteed to protect the air conditioning system, protect the next level of filter
Central air conditioning F7 bag type, no partition filter to prevent tuyere black stains, prevent upholstery fading
School, kindergarten F7 bag type, no partition filter fire special safety consideration
Room and ward F7 ~ F8 bag type, no partition filter to prevent cross infection
Museum and library F7 bag type, no clapboard filter protects treasures
Audio and video studio F7 bag type, no partition filter protects optical equipment and products
Class 100,000 and class 10,000 non-uniform flow clean room HEPA has partition and non-partition high efficiency filter for test one by one, and non-flammable material filter is installed in the high efficiency air supply outlet
Class 100 clean room HEPA
Or ULPA high efficiency filters with or without partitions are scanned to check the clean room end one by one before leaving the factory
General clean room pre-filtration F8 ~ H10 bag type, no partition, with partition filter to ensure the normal service life of the end filter
Chip factory level 10, level 1 clean workshop ULPA no separator ULPA filter scanning inspection, uniform flow rate, no volatile matter. Today’s filter with the highest requirements for filter performance
Pre-filtration HEPA without partition and with partition filter head-on high wind speed ensures the service life of the end filter is “lifetime”.
Class 300,000 clean workshop in pharmaceutical industry
HEPA bag type, no separator, with separator filter filter does not contain nutrients the end filter can be located in the central air conditioner
Negative pressure clean room exhaust filtration HEPA without partition, with partition filter reliable prohibit the discharge of dangerous goods
Car painting line main filter F5 ~ F7 bag filter does not contain silicone, does not lose hair, flame retardant to meet the paint without defects, protect the flow of materials
Car painting line main filter F6 ~ F7 high temperature resistance with partition filter does not contain silicone process requirements
High demand electrostatic spraying workshop F7 ~ F8 bag type, no partition filter does not contain silicone, no hair off to ensure the appearance of no defects
Nuclear power plant exhaust HEPA has partition, no partition filter fire protection, impact resistance, special agency certification
The F5 to F7 bag type filters in the equipment room, switchboard, and central control room of the central air conditioner are used to prevent poor heat dissipation and circuit faults caused by dust
Simple flat filter for G3 ~ F5 of machine room, switchboard and central control room with cabinet air conditioning Because of site restrictions, it is difficult to use other forms of filters for cabinet air conditioning
Chemical fiber drawing process F8 bag filter to prevent broken wire
Spinning workshop G4 ~ F7 bag filter, electrostatic filter to prevent “coal ash yarn”
Food industry F7 bag type, no partition filter nutrition-free production environment hygiene
Clean table, air shower room HEPA with partition, no partition high efficiency filter
Rolling main motor F7 bag filter flame retardant to prevent motor failure caused by dust
Cigarette factory central air conditioning F7 self-cleaning filter device, bag filter Self-cleaning filter device is popular in the domestic tobacco industry
Home central air conditioning G3 ~ G4 flat filter cheap, beautiful placed in the supermarket goods
Ordinary household air conditioning – nylon mesh can be cleaned to block fibers and coarse dust
Pre-filtration in sand-blown areas – inertial dust removal device, water bath dust removal device, rolling filter to remove large particles of dust, only when the wind is blowing
Gas turbine and centrifugal air compressor F7 ~ F8 no partition, bag type, with partition filter, self-cleaning filter anti-impact, flame retardant to prevent scaling, wear, corrosion inside the equipment
Axial flow air compressor F5 ~ F7 no diaphragm, bag filter impact resistance, flame retardant to prevent blade wear
Reciprocating air compressor
G3 ~ F5 bag filter, filter, plate filter impact resistance, resistance to excessive resistance to prevent cylinder wear
Senior car air conditioning F7 No partition filter element dust and pollen proof
Premium household vacuum cleaner F7
HEPA no partition filter element strong, water resistance to prevent secondary pollution of exhaust air
Clean room vacuum cleaner HEPA no partition filter element strong, water resistance to prevent exhaust air secondary pollution
Household air purifier F7 ~ F9