【作者】 刘颖；

【导师】 李安桂；

【作者基本信息】 西安建筑科技大学 ， 环境科学， 2011， 硕士

【摘要】 空调送/回风管道系统是空调通风系统的重要组成部分,也是空调系统中污染较为严重的环节,因此给室内带来的微生物污染是不可忽视的。在适宜的温度湿度等条件下长期运行后,微生物会附着灰尘停留在空调管道及某些部件上大量繁殖,产生并释放有害的浮游菌、颗粒物或代谢产物,这些有害的污染物质将会随送风进入室内,加剧室内微生物污染,从而导致室内空气品质的下降。为深入了解送/回风管道的病原微生物污染生态分布,选取了陕西省历史博物馆这一典型建筑为采样点,建立可控气流参数空调送风管道粒子沉积与微生物污染模型实验台,在多参数可变条件下进行实验室模拟测试,并设计正交试验方法对实验数据进一步分析。微生物鉴别结果表明,G+细菌(革兰氏阳性)占细菌总数的56%,G-细菌(革兰氏阴性)占细菌总数的44%,主要为球菌和杆菌;优势真菌属为青霉属,曲霉属和枝孢霉属。实验室模拟研究结果表明,风速对微生物生长的影响属于间接影响;当风速为2.0m/s时,测试段底面积尘量沿送风方向呈下降趋势,测试段末端积尘量仅为初段积尘量的35%左右;而当风速为3.0m/s时,积尘量呈相对平缓趋势且在0.02~0.05g范围之内;微生物数量与积尘量呈正相关关系,当积尘量提高1倍时,微生物数量可提高2~3倍,细菌数量与积尘量的相关关系较真菌显著(R细菌>R真菌),同一份样品中细菌数量多于真菌数量,约为其两倍;微生物浓度随相对湿度以及温度的升高呈下降趋势,最高可减少至50%,且细菌浓度受相对湿度以及温度影响普遍较真菌的大(R细菌>R真菌)。正交试验得出微生物生长繁殖主要的影响因素为温度;但在风速为3.0m/s的条件下,相对湿度是真菌生长主要影响因素。更多还原

【Abstract】 Air-conditioning supply/return air duct system is an important part of the ventilation system, and it is also the most serious polluted link. Therefore, the indoor microbial contamination should not be neglected. Due to air-conditioning system itself, dust with microorganisms stay in the air-conditioning ducts and certain components, and in appropriate conditions of temperature and humidity for long running, the microorganisms multiply, produce and release harmful bacteria, particulate, or metabolites. These harmful pollutants will inter the rooms and aggravate the indoor microbial contamination, thus leading to a decline in indoor air quality.In order to deeply understand ecological distribution of pathogenic microbial contamination in air supply/return duct, we selected a typical building for sampling points - the Shaanxi Provincial History Museum, established a microbial contamination model of particle deposition experimental air duct with controllable airflow parameter in many parameters variable condition of laboratory simulation test, and designed orthogonal test method for further analysis of the experimental data.Microbial identification results showed that G+ bacteria (gram-positive) accounted for 56% of the total bacterial count, and G- bacteria (gram-negative) accounted for 44% of the total bacterial count, mainly cocci and bacillus; dominant fungi is Penicillium, Aspergillus and Cladosporium.Laboratory simulation study results showed that the impact of wind speeds on microorganism growth is indirect effects; when the wind speed of the test section was 2.0m/s, the amount of dust decreased along the bottom of the test section and the dust amount of the end of test section was the 35% of the initial; and when the wind speed was 3.0m/s, the amount of dust was relatively in a flat trend and in a range of 0.02~0.05g; microbial populations and dust quantity are positively related, when dust quantity improved 1 times, microorganism quantity can raise 2~3 times, the correlation between bacteria and dust amount was more significantly than fungi (Rbacteria> Rfungi),in the same sample bacteria was as two times as fungi; with relative humidity and temperature rising, microbial concentration declined, and the bacterial concentration was affected by relative humidity and temperature was generally higher than the large fungi (Rbacteria> Rfungi). Orthogonal concluded that the main factor of the microbial growth was temperature; but with a wind of 3.0 m/s conditions, the relative humidity is the main influence factor to the fungal growth.更多还原