Study On Emission Characteristics And Pollution Control Of Particulate Matter In Cigarette Side Stream Smoke

A box type environmental warehouse is used to simulate the smoking mode manually,and a ELPI+is used to monitor the number concentration of particles of different particle sizes in cigarette side-flow smoke in the simulated chamber in real time,analyze the particle size distribution characteristics of cigarette side-flow smoke particles during the smoking and combustion process and after the burnout,and quantify the emission rate and decay rate of cigarette side-flow smoke particles.The emission and attenuation characteristics of cigarette side-stream smoke particles are studied.The ELPI+is used to conduct real-time monitoring of particle number concentrations of different particle sizes during and after cigarette smoke combustion under different humidity and activated carbon intervention conditions,to study the influence of relative humidity on particle number concentrations of cigarette side-stream smoke,and to explore the effect of activated carbon dosage on the attenuation of cigarette side-stream smoke particles.The main conclusions are as follows:（1）The distribution characteristics of particle size in the side stream smoke of six types of cigarettes are similar,showing a single peak（"bell"shape）with a peak particle size ranging from 0.382μm to 0.603μm.When two or more cigarettes are lit within a space of 0.3825m³ in the environmental warehouse,simulating the scenario of multiple people smoking,the peak particle size shifts to 0.256～0.382μm.The emission rate range of 6 types of cigarettes in each particle size range is（0.02～7.19）×10⁵·cm^-3·min^-1.In a certain space,the particulate matter emission rate does not increase exponentially when the number of cigarettes exceeds 2;The emission rate of particles with different particle sizes from 2 cigarettes is 3 to 15 times higher that of a single cigarette.（2）During the attenuation process of cigarette smoke particles,the particle size distribution generally maintains a"bell"shaped single peak pattern,and the peak particle size does not shift over time.However,the peak of the"bell"gradually decreases as the smoke particle attenuate.The particulate matter rapidly decays within15 minutes after the cigarette is extinguished,and reaches the environmental background state by approximately 240 minutes.When multiple people smoke cigarettes indoors,the attenuation process of side stream smoke particles shows a trend in the average particle size.Initially,the peak particle sizes ranging from 0.256～0.382μm.Subsequently,they change to 0.382～0.603μm,and then again to 0.603～0.949μm.The particle size distribution is affected by the number of cigarettes in a certain space.（3）Under various relative humidity intervention conditions,there are differences in the concentration of particulate matter emissions from indoor cigarette side stream smoke.When the relative humidity exceeds 50%,a significant condensation phenomenon of particulate matter occurs.Furthermore,when the relative humidity surpasses 60%,there is secondary particle formation that affects the primary emission of particulate matter.Activated carbon does no affect the particle size distribution of cigarette side stream smoke particles.However,it can reduce the generation of secondary particles by adsorbing organic matter emitted in the cigarette smoke.To achieve a significant control effect on the secondary formation of cigarette smoke,the unit space volume of activated carbon needs to be 746.7g/m³ or higher.