Plate filter is a common filtering equipment, which has two types: air filtration and solid-liquid separation. This paper mainly introduces air filtration:

Plate air filter

Structure composition: mainly composed of frame and filter element. Frames are usually made of metal materials, such as galvanized steel plates, and some are made of waterproof cardboard, which is firm or light. The filter element generally adopts polyester synthetic fiber, non-woven fabric and synthetic glass fiber as the filter material.

Working principle: Depending on the pressure difference caused by air flow, air passes through the filter material, and pollutants such as large particles of dust, hair and fiber in the air are intercepted by the filter material, thus achieving the purpose of air filtration and purification.

Characteristic

Advantages: compact structure, light weight and convenient installation and disassembly; The filter material has a large dust holding capacity, can be cleaned and reused, and can reduce the operating cost; Low wind resistance can ensure ventilation and reduce system energy consumption; The price is relatively low.

Disadvantages: the filtration accuracy is relatively limited, and it is generally used for primary filtration; In high humidity environment, the filter material may be affected by moisture; Long-term use or in harsh environment may damage the filter material and need to be replaced in time.

Application: It is widely used in steel, electronics, chemical industry, automobile, environmental protection and electric power industries. It is the inlet filtering equipment of centrifugal compressor filter room, and also used for dust removal, oil removal and coarse filtration of various air conditioning systems. It is also suitable for pre-filtration of centralized ventilation systems in office buildings, shopping malls, hospitals, airports, ordinary industrial workshops or clean rooms.

Cleaning and maintenance of plate filter is the key to ensure its filtration efficiency and prolong its service life. Different types of plate filters (air filtration and solid-liquid separation) differ slightly in specific operation, but the core principle is to keep the filter material/plate clean and the structure intact. The following are detailed cleaning and maintenance methods:

Daily inspection and maintenance

Regular inspection: check whether there is obvious dust accumulation on the filter surface, whether the filter material is damaged (such as holes and tears) and whether the frame is loose or deformed every week. If the filter material is found to be damaged, it needs to be replaced immediately to prevent unfiltered air from entering the system directly.

Cleaning cycle: according to the dust concentration in the use environment, the primary filter is generally cleaned once every 1-3 months; In an industrial environment with a lot of dust, it is recommended to check it every 2-4 weeks and clean it in advance if necessary.

Cleaning method:

Dry cleaning: For reusable filter materials (such as synthetic fibers), first use compressed air (pressure ≤0.3MPa) to reverse blow from the back of the filter material to remove floating dust on the surface; If there is stubborn dust, gently pat the filter material frame (to avoid damage to the filter material caused by excessive force).

Wet cleaning: If the filter material is allowed to be washed (such as some non-woven fabrics), it can be washed with clear water first, then gently wiped with neutral detergent (avoid using strong acid and alkali), and finally washed with clear water and dried in a cool place (insolation or high temperature drying is prohibited to avoid deformation of the filter material).

Replacement standard: When the filter material is cleaned for 3-4 times, the filtration efficiency is obviously reduced (such as the ventilation rate is reduced by more than 30%), or the filter material is irreparably damaged or aged, so it is necessary to replace the new filter in time.