空调风系统积尘伴生微生物种类鉴定与热湿响应特性研究

发布时间：2019-03-08 10:41

【摘要】：空调通风管道是空调系统的重要组成部分,也是空调系统中污染最严重和最容易忽视的部位。在适宜的温湿度条件下,长期运行使用过程中,空气中的微生物附着灰尘沉积在空调管道及其他部件上大量生长繁殖,产生并释放过敏物质、毒素等多种代谢产物,加剧了室内空气的微生物污染。 选取某大型超市,对清洗前后的空调通风系统送风管道的积尘进行采样分析：积尘量,积尘伴生微生物的浓度,送风中细菌总数、真菌总数等指标进行检测,对清洗效果进行评价。并对积尘伴生微生物的种类进行鉴定,明确春末夏初这段时间积尘伴生微生物的优势菌群。设定不同的温湿度条件对积尘伴生微生物的生长特性进行测定,以期找到控制微生物生长繁殖的温湿度条件。 结果表明,清洗后积尘量,积尘中细菌总数、真菌总数,送风中细菌总数、真菌总数大幅度下降,清洗效果显著,对空调运行和改善室内空气品质具有明显作用；积尘伴生微生物中,细菌以革兰氏阳性菌为主,主要的种类是表皮葡萄球菌、藤黄微球菌、蜡样芽孢杆菌和大肠杆菌。真菌种类主要有青霉、曲霉,交链格孢霉、枝孢霉和毛霉,其优势菌群是斜卧青霉和聚多曲霉。 在15℃-50℃C,相对湿度为30%-90%的范围内,积尘伴生细菌的最适生长温度为35℃C-37℃,在相对湿度为30%～90%的范围内,随着相对湿度的增加菌落数增加,尤其是在60%以上；真菌的最适生长温度为25℃C-30℃,在30%-90%的相对湿度范围内,随着相对湿度的增加菌落数增加,在70%以上增长趋势更为明显。 在空调非运行过程中,在45℃-65℃,处理30min,对积尘伴生微生物的灭活作用进行了测定。随着温度的升高,菌落数逐渐减少,直到60℃C-65℃,菌落数较少,处于缓慢变化状态；在相对湿度为60%-10%的范围内,测定了对积尘伴生微生物的灭活作用,随着相对湿度的降低,菌落数逐渐减少,相对湿度到20%时,基本上所有的微生物都被杀死了。对温湿度条件及处理时间进行进一步的优化,得出的最有处理条件是处理40min,温度65℃,相对湿度为10%,微生物的浓度大幅度下降,但微生物的种类几乎没有变化。在空调运行过程中,温度维持在16℃C-24℃C,相对湿度一般维持在60%-90%范围内,在此温湿度范围内,相对湿度越低,菌落数越少。
[Abstract]:Air-conditioning ventilation pipe is an important part of air-conditioning system, and it is also the most serious and easily neglected part of air-conditioning system. Under suitable temperature and humidity conditions, during long-term operation and use, microorganisms in the air deposit dust on air conditioning pipes and other parts to grow and reproduce in large quantities, producing and releasing allergies, toxins, and other metabolites. Increased indoor air microbial pollution. A large supermarket was selected to sample and analyze the dust accumulation in the air supply pipe of air conditioning and ventilation system before and after cleaning: the amount of dust accumulation, the concentration of microorganism associated with dust accumulation, the total number of bacteria and fungi in the air supply system, and so on. The cleaning effect is evaluated. The species of dust-associated microorganisms were identified, and the dominant flora of dust-associated microorganisms in late spring and early summer was identified. Different temperature and humidity conditions were set to determine the growth characteristics of microorganisms associated with dust accumulation in order to find out the temperature and humidity conditions to control the growth and reproduction of microorganisms. The results showed that the amount of dust accumulated after cleaning, the total number of bacteria and fungi in dust, the total number of bacteria in air supply, the total number of fungi decreased greatly, and the cleaning effect was remarkable, which had obvious effect on air conditioning operation and improvement of indoor air quality. Gram-positive bacteria were the main bacteria associated with dust accumulation. The main species were Staphylococcus epidermidis, Micrococcus vines, Bacillus cereus and Escherichia coli. The main fungi are Penicillium, Aspergillus, Alternaria, Cladosporium and Mucor. The dominant flora is Penicillium recumbent and Aspergillus polyspp. In the range of 15 鈩，

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