Study On The Control Method Of Indoor PM_2.5 Concentration

In recent years,the frequency of haze has increased in China,especially in Beijing-Tianjin-Hebei regions.Due to the poor air tightness of doors,windows,and envelopes in most of China’s civil buildings,so outdoor PM_2.5.5 can easily enter the room that can reduce indoor air quality.People spend most of their time working and living indoors,therefore the concentration level of indoor PM_2.5.5 is important for human health.Compared with outdoor pollutants,the sources and components of indoor pollutants are more extensive and complex,and can cause greater harm to human health.Therefore,how to reduce the indoor PM_2.5.5 concentration has become the focus of indoor air quality control,this is an urgent problem that need resolving.In this article,we adopts active control method and passive control method to explore the method of efficient removal of indoor PM_2.5.The following four aspects are studied,respectively:（1）The relationship between indoor and outdoor PM_2.5concentration levels.Mainly studied the law of PM_2.5.5 concentration changes in indoor environment when the outdoor PM_2.5.5 concentration changes and its influencing factors when outdoor haze has been occurred.This provides a basis for us to find out the source of indoor PM_2.5.5 and find out the method to control PM_2.5concentration.PM_2.5.5 permeation factor was also calculated from indoor and outdoor PM_2.5.5 concentration,so it can find the passive control method of indoor PM_2.5concentration.（2）To study on the removal effect of PM_2.5.5 on air purifier.we mainly study how the air purifier can remove particulate matter such as PM_2.5.5 at different particle sizes under hazy weather,and whether the different relative humidity and air flow have any effect on the purification efficiency of air purifiers in purifying PM_2.5and other particles.（3）Analysis of the chemical components of the particulate matter that adsorbed in the air purifier filter,it’s provided the basis from the source to controlled indoor PM_2.5.5 and other particulate matters.We mainly analyzed the components of water-soluble ions,metal elements,and polycyclic aromatic hydrocarbons（PAHs）in PM_2.5.5 and other particulate matters on the filter.We also used source analysis method to analyze the sources of PM_2.5.5 and other particulate matters,and evaluated the health risks of heavy metals and PAHs.（4）The numerical simulation method was used to study the control effect of the new fan on PM_2.5concentration in the room.The CFD numerical simulation software was used to study the effect of the new fan on the removal of PM_2.5.5 and other particles in the room under different new air return patterns.