中国严寒地区住宅建筑室内细菌气溶胶污染特征及传播规律

Pollution characteristics and transmission of indoor bacteria aerosol in residences in China’s severe cold regions

实测严寒地区住宅建筑细菌气溶胶组分及来源,并结合微生物生长繁殖衰亡模型和数值模拟技术开展细菌气溶胶传播特性研究.结果表明,中国严寒地区住宅建筑室内的主要优势菌群为拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)、变形菌门(Proteobacteria).而细菌的来源分析显示,其主要来源为粪便、土壤、极端环境、植物、水源和腐败有机物等.由于冬季人员室内活动时间较长,其中粪便来源占比偏高.细菌在室内的传播规律研究表明,在室内环境中细菌气溶胶的浓度分布与房间的结构、湍流形式和粒子重力场有关.随着房间高度的降低,室内流场越复杂.模拟分析表明室内90%的细菌气溶胶颗粒在50s内逃逸出,且随着房间高度的降低细菌气溶胶浓度逐渐降低而范围更广.室内通风有阻碍细菌气溶胶在室内积聚,稀释污染浓度的作用.

To explore the transmission characteristics of indoor and outdoor microbial aerosols in residences of severe cold areas,this study was conducted by combining microbial growth models and numerical simulation techniques.The main dominant bacterial flora in residential buildings were Bacteroidetes,Firmicutes,and Proteobacteria.The analysis of the source of bacteria showed that the main sources were manure,soil,extreme environments,plants,water sources and decaying organic matter.Among them,the proportion of manure sources was relatively high due to the long indoor activities in winter.Research on the propagation law of bacteria in the room showed that the concentration distribution of microbial aerosol in the indoor environment was related to the structure of the room,the form of turbulence and the particle gravity field.Indoor ventilation could hinder the diffusion of microbial aerosols.As the height of the room decreases,the indoor flow field became more complex.Simulation analysis showed that 90%of the bacterial aerosol particles in the room escaped within 50s.And as the height of the room decreases,the concentration of bacterial aerosol gradually decreased,and the range became wider.Indoor ventilation had the effect of preventing the accumulation of bacterial aerosols in the room and diluted the concentration of pollution.