Project CategoryMain project classification
With the development of social economy, the HVAC industry has developed rapidly in recent years. People's life, work and product production technology have put forward higher requirements on the technical level and product quality of the HVAC industry. The industry has conducted extensive and in-depth research on the problems of ill-conditioned building syndrome, air conditioning syndrome, and building energy saving in the construction industry in recent years. However, there are still many problems that cannot be solved, such as irrational design, poor product quality, and poor control. Perfect and much more. Among them, the improvement of air quality is one of the important issues that the HVAC industry needs to solve urgently. Some experts and technicians analyzed the reasons and proposed a series of solutions at various seminars. However, due to the constraints of investment, energy saving and other problems in engineering practice, it is always difficult to solve the fundamental problems. There are many factors that affect indoor air quality. The optimized design of the system, the amount of fresh air, and the performance of the equipment can have an important impact on air quality. To improve the indoor air quality, it must be controlled from every link of air circulation. The filtering effect of purifying the return air port is an important link that has been neglected. The return air vent is one of the necessary devices in air conditioning and purification projects. In the project, due to its small cost and occupation ratio, simple structure, it is difficult to attract the attention of designers and users. It is usually regarded as a small product, and only pay attention to its The appearance is decorative and neglects its use function. In fact, the filter performance of the return air outlet is one of the necessary conditions to keep the air conditioning and purification environment in line with requirements. The quality of its material affects the degree of deformation of its blades, which affects the resistance and aesthetics of the return air, improper surface treatment, easy to accumulate dust and difficult to clean, incomplete surface oxidation and uneven blackening.
At present, the return air outlet of air conditioning and purification places and its filtering usually have the following common forms:
The first is a layer of nylon mesh on the return air outlet;
The second method is to add a filter made of multi-layer metal mesh to the return air outlet;
The third type is only the return air port without any filtering.
The method without filtering has proven to be unsatisfactory. Not only can it not meet the use function, but also part of the return air vents become passages for small animals and insects, and it can also be a place for low-quality staff to discard debris at will. At present, there is no specific requirement for the efficiency of return air filtration in the design, and there are no corresponding provisions in national standards and industry standards. Therefore, only one layer of nylon filter is added to the product. In common semi-centralized air-conditioning systems with fan coils and fresh air, a single layer of nylon mesh basically does not function as a filter. When the particles and fiber pollutants in the air are circulated to the air cooler of the fan coil unit, the condensed water will stick to the surface cooler, and a part of the water droplets will enter the water condensate tray, and these pollutants will become a hotbed for bacteria to attach and reproduce. The dust deposited on the surface cooler can also reduce the efficiency of the heat exchanger, increase the energy consumption of the entire air conditioning system, and fail to achieve the use effect. Some managers found that after running the air-conditioning system for a period of time, the wind blown by the air-conditioner had an unpleasant odor when it was turned on, and it was impossible to adjust the temperature to the design temperature on time. After analysis, the contamination of the surface cooler and the decrease in heat transfer performance are the direct causes. It is extremely difficult to clean the surface cooler. The multi-layer metal wire mesh is stamped from a very thin metal plate, and its surface is not smooth and has a lot of burrs. Fibrous pollutants generated by bedding, carpets, etc. are attached to it in hotels, office buildings, and hospital wards. It is difficult to clean. Due to poor management and poor quality of staff in some air-conditioning places, the air-conditioning system failed to meet design requirements during operation. Relevant personnel made a systematic survey of the operation of the air-conditioning system in several large shopping malls and hotels in Dalian, Yantai, and Qingdao. It was found that most air-conditioning systems showed severe blockage of unit filters and reduced unit efficiency after one year of operation. In order to reduce the workload of manual cleaning, some maintenance managers even removed the filters of the return air outlet and the air-conditioning unit, resulting in deterioration of air quality, severe black stains on the air outlet, rapid aging of the interior decoration, and reduced staff efficiency. In some guest rooms and hospital wards, because of heavy fluff pollutants on bedding and carpets, a thick layer of debris is attached to the surface cooler of the fan coil unit and the condensate tray. After opening the inspection port, you smell a odor It's no wonder that staff members often report dizziness and nausea.
3. Improvement measures
The filtering effect of air conditioning purification return air filter is an important factor affecting indoor air quality. It is of great significance in protecting end equipment and preventing cross-contamination of pollutants. In clean projects, increasing the efficiency of the return air filter can help prevent the degree of cross-contamination of pollutants from different workshops, and extend the service life of medium and high efficiency filters. The installation position of the return air filter is convenient for removal and replacement, does not affect the operation of the entire air conditioning system, and is convenient for decentralized management and control. The disadvantage is that the increase in the efficiency of the return air filter will increase its resistance. Some foreign designs usually increase the area of the return air to reduce the speed of the return air, thereby offsetting the requirements for the fan head. It is reasonable. At present, there are many filter materials on the market, which are sufficient to meet the requirements of filtration efficiency. However, the structure of the air outlet is difficult to remove and replace the filter screen, which restricts the selection of filter materials. Some openable air outlets are unreasonable in structure and tightly sealed. Can not meet the requirements, there is no good connection, easy to relax, rust, block. Some bead-type openable air vents are too strong when they are opened, which easily damages the decorative surface and deforms the air vent. Manufacturers and product developers should research and reform the structure of air conditioning purification air outlets, and develop practical new products. At present, the combined air outlets produced by some manufacturers have basically met the requirements for use, and can be easily disassembled and increased. The return air filtration efficiency. Designers should pay attention to the role of air conditioning purification return air filter to ensure the life of the end equipment and heat exchange efficiency. So as to ensure the normal operation of air quality and air conditioning system. Relevant departments should also organize experts and technicians to formulate relevant industry standards to limit the efficiency of the return air filter in order to better meet the needs of people's lives and work and the requirements of the production environment on the production process of the product.
Related links: Dongguan air-conditioning purification project, Dongguan dust-free purification equipment, Changan central air-conditioning project, low-voltage power distribution project, Dongguan purification ventilation project, Dongguan dust-free purification project, hydropower installation project, Dongguan 100,000-level dust-free workshop, Dongguan City Power Xiang Air Conditioning Purification Engineering Co., Ltd.
Article source: http://jimesale.com Tan Yuming 13751461639