The development prospect of air filter
The prototype of the air filter is a respiratory protection device used by people to protect the breath. According to records, as early as the first century in Rome, people used hemp masks for protection when they purified mercury. In the long time since then, air filters have also made progress, but they are mainly used as respiratory protection devices in some dangerous industries, such as the production of hazardous chemicals. In 1827, Brown discovered the law of motion of tiny particles, and people have a better understanding of the mechanism of air filtration.
The rapid development of precision air filters is closely related to the development of the military industry and the electronics industry. During the First World War, due to the use of various chemical poisons, military gas masks with asbestos fiber filter paper as the smoke filter layer came into being. Glass fiber filter media for air filtration was patented in the United States in October 1940. In the 1950s, the United States conducted in-depth research on the production process of glass fiber filter paper, which improved and developed air filters. In the 1960s, HEPA filters came out. In the 1970s, the HEPA filter using fine glass fiber filter paper as the filter medium has a filtration efficiency of 99.9998% for particles with a particle size of 013 microns. Since the 1980s, with the emergence of new test methods, the improvement of use evaluation and the improvement of filtration performance requirements, it has been found that HEPA filters have serious problems, so higher performance ULPA filters have been produced. Currently, countries are still working hard to study, it is estimated that more advanced air filters will appear soon.
Significant progress has also been made in the design of the filter itself, the most important of which is the removal of partition plates, that is, the development of filters without partitions. The partitionless filter not only eliminates the risk of the partition plate damaging the filter medium, but also effectively increases the filtering area, improves the filtering efficiency, and reduces the airflow resistance, thereby reducing energy consumption. In addition, air filters have made great progress in high temperature resistance, corrosion resistance, waterproofing, and anti-bacterial aspects, which meet some special needs.
Application of air filter:
With the increasingly serious environmental pollution and the strengthening of people's environmental awareness, air quality has become the focus of attention all over the world. People now realize that air filtration systems must not only protect mechanical equipment, but also protect people. Therefore, the application range of air filtration is becoming wider and wider.
The largest application of air filtration is residential buildings, followed by commercial and industrial buildings. In addition, filtration equipment is also commonly used in the following occasions: clean rooms; copy equipment; indoor air purifiers; anesthesia gas filtration equipment; laser surgery applications; HVAC systems (heating, ventilation and air conditioning systems); constant temperature rooms; computer printers; studios Air filtration system; air conditioner, etc.
1. Air filter housing market:
Due to the continuous improvement of people's requirements for the quality of life, the original air filtration system of the house can no longer meet people's needs, and the higher performance electrostatic filter has become the first choice for the original air filter. However, compared with ordinary glass fiber filters, the application of electrostatic filters is also subject to certain restrictions due to the higher cost of filter media.
Bailun company is the leader in the electrostatic filter market. Its products adopt a corrugated structure, and the media is loosely packed, so the airflow resistance is small. Bailun Company said that the packing density of their filter is the most suitable and has a long life. The corrugated structure also improves filtration efficiency and can trap more particles than flat filters.
In China, most houses do not have air filtration systems, but the number of houses in China is huge, and it is increasing at a rate of millions of units every year. As the indoor air quality becomes worse and people's environmental awareness continues to increase, there is a huge potential market for air filtration systems in residential applications.
2. Air filter office building application:
The driving force for improving office air quality is the wide application of advanced office equipment. Computer terminals are a source of ozone and volatile organic compounds. Inkjet printers are a source of hydrocarbons and ozone. Dry photocopying machines produce hydrocarbons, respirable suspended particles and ozone; fax machines produce ozone and volatile organic compounds; laser printers produce hydrocarbons, ozone and respirable particles; etc. These products have seriously polluted the indoor environment and caused certain harm to people and office equipment.
It is estimated that 30% of office buildings and public buildings in the United States have indoor air pollution problems. In particular, public buildings such as airports and train stations face far greater challenges than office buildings. The air flow in the lobby of Chicago D'Hare Airport is about 51.66 million m3 per minute. In order to improve the air quality, there are a total of 1,100 pre-filters, 1,100 final filters and 2,200 carbon filters (the charcoal is used every 10-12 months). Need to be replaced once).
It is estimated that in 2000, the global demand for air filters in offices, commercial and public buildings will reach 500 million US dollars.
3, air filter indoor air purifier application:
With the increasingly strict building standards, consumers are paying more and more attention to indoor air quality. Especially people suffering from allergies, asthma or respiratory diseases, because air pollution affects their normal lives. People spend 90% of their time indoors, and indoor air pollution levels may be 2 to 5 times that of outdoors. Almost all indoor spaces contain pollen, mold, spores, animal hair, smoke, bacteria, viruses, and harmful fibers and dust including asbestos. Poor air quality makes asthma and allergies worse. Using an air purifier to remove indoor air pollutants is an effective method.
There are many products on the portable indoor air purifier market. The fastest growing is the use of high-efficiency filter media electrostatic air filters such as 3M's Filtrete, and more efficient fine glass fiber HEPA filters, they occupy most of the market. The air purifier market in the United States is increasing at an annual rate of more than 10%. Japan is the second largest market after the United States. In China, the demand for air purifiers is also gradually increasing. With the continuous deterioration of air quality and the emergence of home offices, air purifiers will have a huge potential market.
4. Air filter production plant application:
Different factories have very different air quality requirements. Factories equipped with fume hoods and pollution control equipment need to supplement a large amount of air. If the ambient air in the area where these factories are located is polluted, the supplemental air must be filtered before being distributed to the workplace. In the semiconductor production and pharmaceutical industries, the air cleanliness requirements are relatively high. In a typical working environment, there are 500,000 particles per cubic foot of air, and the latest requirement for semiconductor production is that there is only one particle per cubic foot of air. Therefore, the workplace needs to be cleaned continuously with clean air filtered by HEPA filters. In order to maintain the cleanliness and longevity of the HEPA filter, several pre-filters with lower efficiency are required to be combined.
Industrial clean rooms require continuous and effective removal of smaller particles. The HEPA filter was once the most efficient filter, but now the ULPA filter is the most efficient filter. In the future, a new generation of more efficient filters will also be developed and applied. Micro glass fiber filter media is the main choice for filter media, but membranes and electrostatically enhanced media have penetrated into this field and have been partially applied.
For the exhaust gas emitted by the factory, the most stringent requirement is toxicity. Certain heavy metals such as mercury, arsenic, chromium, and beryllium are very toxic, and their emission limits are very strict. In terms of air toxicity, the United States and Germany have passed new and stricter legislation. After the implementation of the new legislation, the air toxicity limit has been reduced from the original 20mg/m3 (standard) to 010004mg/m3 (standard). To achieve this goal, factories need more advanced high-efficiency air filters to remove sub-micron particles. Some German companies use the traditional foldable micro glass fiber HEPA filter for the filtration system, which cooperates with the pulse air cleaning mechanism and makes the ripples of the filter medium denser. An American company has taken another step forward by designing a tubular micro-glass fiber HEPA filter.
5. Air filter hospital application:
The sanitation industry is a very large and special industry, and it also requires high air cleanliness. Generally, the minimum requirement for hospital air is a combination of a pre-filter with an efficiency of 30% and a final filter with an efficiency of 90%. Under normal circumstances, HEPA filter is not required, but in special circumstances such as isolation rooms, specific testing and care areas, HEPA filters are required.
Many HVAC systems in hospitals use 100% outdoor air, which is a good strategy for preventing patients from cross-infection by suspended microorganisms in the HVAC system. However, 100% use of outdoor air cannot eliminate the growth of microorganisms in the air filter medium and its adverse effects on the care environment. Therefore, many hospitals still need advanced HVAC systems.
The clean room of the sanitation system was first used in the operating room. At first it was widely used in orthopedic surgery, because orthopedic surgery takes a long time and is prone to infection. The ideal control level is to use the air cleanliness near the operating table to reach level 100. It is generally recommended to use the top HEPA filter system, which can cover an area of at least 3m×3m to include the operating table and people.
Other areas where clean rooms are used include delivery rooms, nursery rooms, burn rooms, heart patients care units, etc. One of the latest developments is the application of clean rooms for dental surgery, which reduces the risk of infection of medical staff during long-term operations.
6. Air filter food processing application:
The food industry is becoming an expanding market for air filtration equipment. In order to maintain the fresh taste of food, the method of disinfection to eliminate pollution has been gradually not used. This makes the elimination of product-related air pollution even more important. National regulations, insurance awareness and public concern are prompting meat processors, dairy producers and other food producers to update their air filtration systems.
In Europe, the canning of yogurt is carried out under clean room conditions. As a result, the product can be stored for a long time without adding expensive chemical preservatives.
The brewery found that in order to protect their draft beer, it is necessary to control the air pollution around the bottling plant. Filling in a clean room is the best choice. This type of factory requires a 100,000-class clean room, which can use a top ventilation system and filter with a HEPA filter.
Looking forward to the future air filter market, we can find:
(1) In the current air filter market, filters with fine glass fiber as the filter medium still dominate, but membrane manufacturers are also developing in the air filtration field, providing high-efficiency membrane filters, and improving membrane performance. Filter performance under air resistance. They believe that membrane filters will soon replace micro glass fiber filters in high-efficiency air filtration and dust collection applications.
(2) The development of high temperature filters will accelerate. Metal fiber and ceramic fiber filters have been applied. The glass fiber composite inorganic membrane can enhance the mechanical properties of the fiber, and endow the filter bag with strong high temperature resistance, so that it can be used at temperatures up to 480°C. Thermal power engineering, coal gasification systems and waste incineration systems will provide a huge market for high temperature filters.
(3) The development trend of the air filter market is globalized. The purchasing growth rate of developing countries will be faster than that of developed countries.
The factors that will stimulate the rapid development of the filter market in the next few years include:
①The construction of a large number of new factories in developing countries;
②The economic recovery of developed countries such as Europe and Japan;
③ There are stricter requirements for environmental protection worldwide. This combination of needs, prosperity and environmental awareness will inevitably stimulate the rapid development of the filter market.