Update: 2020-01-06 16:47 Source: LUFTMY
In Beijing, many primary and secondary schools and kindergartens have installed air purification equipment. Previously, the Beijing Education Commission has proposed that each district can carry out the pilot work of installing the campus fresh air system, and many schools have corresponding plans.
Fresh air fan
The fresh air system is to supply fresh air to the room with special equipment on one side of the enclosed room, and then discharge it from the other side to the outside. A "fresh air flow field" will be formed in the room, so as to meet the needs of indoor fresh air exchange. (the direct point is to complete the exchange of indoor and outdoor air, with the function of ventilation)
Is it good to install fresh air system in the classroom?
The classrooms are densely populated, with poor air circulation and dirty air. In haze days, the doors and windows of the classrooms are usually closed, resulting in the lack of indoor air circulation, the increase of indoor carbon dioxide and various harmful gases. The students stay in the classroom for a long time, and the air quality of the classroom directly affects their health and learning effect. Their resistance and immunity are weak, and their respiratory system is not fully developed Good, easy to be invaded by bacteria and viruses, affecting development and growth. At this time, the most effective way is ventilation.
How about the purification effect of the fresh air system?
In foreign countries, because the energy structure and industrial structure of western developed countries are relatively reasonable, the economy is relatively developed, the investment in environmental protection is large, and the concentration of outdoor PM2.5 is very low, they only need to use heat exchanger to recover heat, ventilate and exchange air while ensuring the minimum energy loss.
But in China, under the condition of bad outdoor environment, the air without pretreatment is not suitable to enter the room. Even though the fresh air system can filter PM2.5 and other particulate matters in the air, the purification effect is good only at the air outlet, but it can not achieve the purification of the whole house. And the realization of indoor and outdoor air replacement will cause certain air conditioning load.
If pure clean fresh air is used to replace the dirty air in the room, it is true that the ventilation with large volume of air can really control the indoor environment very well. Because a large number of fresh air dilutes the indoor gaseous pollutants, a large number of exhaust air will take away the indoor PM2.5 (suspended particles). However, no matter how high the heat exchange efficiency is, there will be energy loss. There are 50 children in each classroom. The heating capacity of each child is 100W per hour and 4kw per hour. If the fresh air is replaced and the energy loss of each classroom is controlled within 4kw, the indoor heating will not be affected. If the amount of fresh air is too large, the indoor temperature will gradually reduce.
In general, large buildings such as school classrooms have many active people and must be ventilated manually, so the fresh air system is standard. But now the haze is more and more serious, so a filter system is added to the fresh air.
At present, the main problem of the fresh air system in China is that it can't open windows and ventilate in the haze. Many businesses boast that the fresh air system is close to omnipotent. In fact, this kind of publicity is very irresponsible.
The existence of fresh air system is to complete indoor ventilation without opening windows. Filtering PM2.5 is only an additional function, not its original purpose. Therefore, indoor air purification must be completed by air purifier to remove indoor PM2.5 and pm0.3 more effectively. The fresh air system is to introduce fresh air from the outside, and the air purifier is to purify the indoor air. The fresh air does not conflict with the air purifier. The fresh air is responsible for ventilation and the air purifier is responsible for purification. This is the responsibility of each of them. Only by improving their strengths and complementing their weaknesses and cooperating with each other can the environment be more conducive to the growth of children.
The LUFTMY infrared counter jet particulate matter sensor hpd05 uses the optical scattering principle to detect the dust concentration in the air. The sensor hpd05, which monitors the air quality, has stable detection ability, high production efficiency and dual advantages. The sensor hpd05 of fresh air system has the characteristics of small volume, high precision, low power consumption, short response time, stable operation under high dust concentration, etc. the infrared opposed particulate matter sensor can be applied to instruments such as fresh air system or environmental improvement equipment.
LUFTMY PM2.5 laser dust sensor ld15 is a high-precision particle concentration sensor based on laser Mie scattering theory. The sensor monitoring air quality can continuously collect and calculate the number of suspended particles with different particle sizes in the air per unit volume, i.e. particle concentration distribution, and then convert it into mass concentration, and output it in the form of general digital interface. The sensor ld15 of LUFTMY fresh air system has the characteristics of small volume, high precision, strong anti-interference, low power consumption, long service life, short response time of zero error alarm rate, etc. the PM2.5 laser dust sensor can be embedded in various instruments or environmental improvement equipment related to the concentration of suspended particles in the air, such as fresh air system, to provide timely and accurate concentration data.
Fresh air is external circulation, air purifier is internal circulation, only the combination of internal and external circulation is the best scheme. Only the combination of fresh air purifier and air purifier is the best solution.
LUFTMY focuses on the research, production and sales of optical particle sensor technology. Guided by the corporate culture of "craftsmen build dreams" and adhering to the service tenet of "customer first", LUFTMY has occupied a high market share in the domestic and foreign markets of PM2.5 sensor. The sensors such as lejmay dust fine particle concentration sensor are widely praised by the industry in measuring accuracy, stability, consistency error, anti-interference and other performance indicators.