The Research On Source Of Indoor Particulate Matter And Control Method

The deterioration of air quality,frequent fog haze weather and the outdoor PM2.5 concentration exceeds bid badly causing the attention of people.In recent years,the way of people’s live and work have changed a lot,and the time of people staying indoors almost account for 80-90%,but the indoor air is inseparable with the part of the atmospheric environment.Therefore,the particulate matter pollution of indoor environment in our country has been quite serious under the big environment pollution.At present,there have not formulated environmental standards of indoor PM2.5 in our country,and the research of indoor fine particulate matter is also in its infancy.So people couldn’t have the true perception of various influencing factors on the influence of indoor air quality with few researches.The paper’s research object is the variation of indoor ultrafine particle concentration in residential building,researching the changes of indoor particle concentration by testing the indoor air pollution（smoking,cooking and secondary dust）,outdoor air infiltration and the particle sedimentation.Meanwhile,the paper studied the purification effect of air purifier and fresh air purification system to the indoor PM2.5 concentration.The results show that the tiny particles that produce from cigarette smoking is mainly PM1,which will make the indoor particulate matter concentrations instantly increase to 1000μg/m3.And the PM2.5 density of the long time smoking room is 0.6-0.8 times higher than the no smoking room.Cooking activities also increase the indoor particulate matter density in different degrees.For examples,the cooking way of fried type contributions to the growth of indoor particulate matter concentrations is the largest,and then the cooking way of stir-fried vegetables and Fried,and the contribution of cooking is at least.Opening the smoke lampblack machine during cooking can quickly emit the particulate matter inside the kitchen and reduce the influence of particles inside the kitchen to the adjacent room.The secondary dust,walking,dressing,bedding etc,will make the room PM2.5 concentration increase from 40% to 70%.The doors and windows of living building are generally in a off state in winter when the fog is frequent.At such a case,the ratio of inside and outside PM2.5 is at around 0.5 for the second step of energy saving residential chamber when the outdoor wind speed is low,and the ratio will get more bigger when the wind speed gets bigger.However,the ratio will always be about 0.48 for three-step energy-saving residential buildings.The indoor PM2.5 concentrations remain downward trend no matter how change of the outdoor air quality when the residential building doors and windows gap are completely sealed,and the sedimentation rate is 0.002min-1,which show that the window aperture is the main channel for outdoor particulate matter into the indoor.The air purifier can reduce well the concentration of particulate matter in the single room when the outdoor particle concentration is higher.Opening air system is efficacious to reduce indoor particulate matter and CO₂ concentration when the fine particulate matter mainly comes from the indoor pollution sources and the residential buildings equipped with air purification system;opening circulation system when the indoor particulate matter comes from outdoor,otherwise,the fresh air system will increase the indoor heat load.