Research Of Air Purification Based On Low-Temperature Condensation

Particulate matter is one of the main pollutants harmful to indoor environment.Although conventional particulate matter purification technologies such as air filtration technology and electrostatic precipitator technology have high purification efficiency for particulate matter,they also have some inevitable defects.In industry,water vapor phase change pretreatment technology is used to increase the particle size,so as to improve the efficiency of particle purification.However,there is no research on the application of this technology in indoor particle purification.The possibility of water vapor condensation phase change technology purifying indoor particulate matter is worth studying.This paper summarizes the filtration mechanism of particulate matter,the effect of infiltration deposition on indoor particulate matter concentration and the model of condensation and growth of the particulate matter under the low-temperature condensation mechanism.A low-temperature condensation purification device is built,and the purification efficiency of the device is tested.The effects of PM2.5 initial concentration,air volume,relative humidity and condensed water volume on the purification efficiency of particulate matter are studied.The results showed that the purification efficiency of the low-temperature condensation purification device can reach80.1%.The purification efficiency of particulate matter is directly proportional to the initial concentration of PM2.5.With the increase of air volume,the purification efficiency of PM2.5 increased,then decreased,and then continued to increase.The purification efficiency of PM2.5 has a positive correlation with the amount of condensate.The lowtemperature condensation can make the water vapor of the air condense on the particles,and increase the particle size of the particles.The particles with the increased particle size are easier to be intercepted,thus improve the purification efficiency of the particles.In order to further study the effect of low-temperature condensation technology on the purification of indoor particulate matter,an air conditioner and a dehumidifier were used as experimental devices to test the purification efficiency of two devices based on low-temperature condensation mechanism.The influence of different factors on the purification efficiency of indoor particulate matter was analyzed,and the fitting formula between the purification efficiency of particulate matter and the amount of condensation water was obtained.The results showed that the air conditioner and dehumidifier have good purification effect on indoor particulate matter,and the highest purification efficiency can reach 60.99% and 85.8% respectively.The relationship between the purification efficiency of particulate matter and the amount of condensate in the low temperature condensation process is a power exponential function.The larger the amount of condensate,the higher the purification efficiency of indoor particulate matter.Therefore,when the equipment has condensation dehumidification capacity,it also has a certain indoor particulate matter purification capacity.This paper provides a new idea for indoor particulate matter purification,and lays a solid foundation for the promotion and application of new indoor air purification technology.