【作者】 王帅；

【导师】 崔政伟；

【作者基本信息】 江南大学 ， 机械工程， 2023， 硕士

【摘要】 新冠疫情在全球爆发以来,室内环境污染与微生物气溶胶的传播受到特别的关注。臭氧水作为高效、全能、绿色环保的消毒剂,在控制微生物气溶胶污染领域具有广泛的应用价值。由于臭氧水制备技术和装备的不完善,导致较难获得高浓度臭氧水使其杀菌效果大打折扣。本课题设计一款高浓度臭氧水空气消毒机,研究不同臭氧-水混合强化装置强化臭氧传质的性能,并通过实验研究高浓度臭氧水空气消毒机对室内微生物消杀效果。主要研究内容如下:（1）设计制造了高浓度臭氧水空气消毒机,并对内部流场进行数值模拟。设计了孔板空化器与静态螺旋切割器两种型式的臭氧-水混合强化装置,采用20 G·H^-1的臭氧发生器,2 m³·h^-1的不锈钢多级离心泵。使用Fluent模拟方法研究了填料喷淋塔塔体的不同进口数量、进口角度和进口高度对流场的影响,模拟结果表明塔体采用3个进口、10°进口角度、100 mm进口高度时塔内气体分布不均匀度σ=0.576 m·s^-1,此结构参数下塔内气体的均匀性最好。（2）实验研究不同结构孔板空化器和静态螺旋切割器强化臭氧传质的效果。以臭氧水平衡浓度、羟基自由基浓度、臭氧传质系数和设备成本能耗为评价指标,对比孔板空化器与静态螺旋切割器的效果,研究不同工艺参数强化臭氧传质的效果。结果表明:采用孔板空化器,臭氧水平衡浓度和羟基自由基浓度随孔口数量N和孔板厚度T的增加而上升,随着孔口直径d的增加而下降。当N=4、d=2 mm、T=4 mm时,臭氧水平衡浓度和羟基自由基浓度分别为10.68 mg·L^-1和110.75μmol·L^-1。对于静态螺旋切割器,臭氧水平衡浓度和羟基自由基浓度随流道数F和相对转角φ的增加而上升,随着螺距m增加先上升后下降。当F=5,φ=720°,m=0.5时,臭氧水平衡浓度和羟基自由基浓度分别为14.12 mg·L^-1和95.85μmol·L^-1。采用静态螺旋切割器为臭氧-水混合强化装置,臭氧水平衡浓度随初始温度和初始p H的增加而下降,随臭氧进口流量增加而上升;羟基自由基浓度随初始温度先上升后下降,随初始p H和臭氧进口流量增加而上升。当初始温度25℃,p H=7,臭氧进口流量3 L·min^-1时,臭氧水浓度和羟基自由基浓度分别为14.12 mg·L^-1和95.85μmol·L^-1。（3）以温度、初始臭氧水浓度、风速和喷淋流量为单因素探究工艺参数对除菌效率的影响,并以除菌效率为响应值建立响应面分析模型和响应面回归方程,得出最佳工艺参数。结果表明:影响次序为初始臭氧水浓度>温度>风速>喷淋流量,得出最佳工艺参数:温度为24℃、初始臭氧水浓度为11 mg?L^-1、风速为2.6 m?s^-1、喷淋流量为510 L?h^-1,并以此参数进行实验,得到平均除菌效率为98.15%。本课题设计研究一种高浓度臭氧水空气消毒机,通过对臭氧-水混合强化装置的研究,实现臭氧的高效溶解,提升传质效率,并利用响应面分析方法确定高浓度臭氧水空气除菌的最佳参数,可以为解决室内空气中微生物污染问题提供较佳的选择。更多还原

【Abstract】 Since the Coronavirus disease-2019（COVID-19）burst in global,the pollution of the indoor environment and the spread of microbial aerosols have been specialy attracted attention.Ozone water as an efficient,versatile,green and environmentally friendly disinfectant,it has widely application value in the field of controlling microbial aerosol polltuion.Due to the imperfection of ozone water preparation technology and equipment,it is difficult to obtain high-concentration of ozone water,which greatly affects the sterilization effect.This current study designs a novel equipment for preparation ozone water in high-concentration for air sterilization.The performance of different ozone-water mixing and strengthening devices for enhances ozone mass transfe were investigated,and the sterilization effect of it on indoor microorganisms were also investigated.The main research content is as follows:（1）A rig for high-concentration of ozone preparation and air sterilization was designed and manufactured,and the internal flow field was then simulated.Two types of the ozone-water mixing and dispersed device of orifice plate cavitator and static spiral cutter were investigated in detail.A 20 G·H^-1 ozone generator and 2 m³·h^-1 stainless steel multi-stage centrifugal pump were chosen in experimental.The effects of numbers,angle and height of inlets,on the flow field were studied using the Fluent simulation.The simulation results show that the best gas distribution unevenness index is 0.576 m·s^-1 in the tower with 3 inlets,10°inlet angle and 100mm inlet height.（2）The effects of different structures of orifice plate cavitators and static spiral cutters for enhances ozone mass transfer were investigatedusing equilibrium concentration of ozone water,concentration of hydroxyl radical,ozone mass transfer coefficient and energy consumption cost as evaluation indexes,and the effects of different process parameters for enhaning ozone mass transfer were investigated,and effects between orifice plate cavitator and static spiral cutter were also compared,the effects of The results showed that,for orifice plate cavitator,the equilibrium concentration of ozone water and concentration of hydroxyl radical increased with the increase of orifice number（N）and orifice plate thickness（T）,but decreased with the increase of orifice diameter（d）.When N=4,d=2 mm,T=4 mm,the concentration of ozone water and concentration of hydroxyl radical were 10.68 mg·L^-1 and 110.75μmol·L^-1,respectively.For static spiral cutters,the equilibrium concentration of ozone water and concentration of hydroxyl radical increased with the increase of the number of channels（F）and the relative angle（φ）,and first increased and then decreased with the increase of pitch（m）.When F=5,φ=720°,m=0.5,the concentration of ozone water and concentration of hydroxyl radical were 14.12 mg·L^-1 and95.85μmol·L^-1,respectively.Therefore,the static spiral cutter was finally used as strengthening device for ozone-water mixing.For process parameters,the concentration of ozone water decreased with the increase of initial temperature and p H,and increased with the increase of ozone inlet flow.The concentration of hydroxyl radical increased with initial temperature and then decreased,and increased with initial p H and ozone inlet flow.When the initial temperature was 25℃,p H was 7,and the ozone inlet flow was 3 L·min^-1,the concentration of ozone water and concentration of hydroxyl radical were 14.12 mg·L^-1 and 95.85μmol·L^-1,respectively.（3）Temperature,initial concentration of ozone water,wind speed and spray flow rate were used as single factors to explore the effects of process parameters on the sterilization efficiency,and the response surface analysis model and response surface regression equation were then established with bactericidal efficiency as the response value to obtain the optimal process parameters.The results showed that the order of influences was initial concentration of ozone water>temperature>wind speed>spray flow rate.The optimal process parameters were obtained as following:temperature 24℃,initial ozone water concentration 11 mg?L^-1,wind speed 2.6 m·s^-1,and spray flow 510 L·h^-1.The average bactericidal efficiency was 98.15%.In this study,the machine for air sterilization with high-concentration of ozone water was designed and studied by strengthening gas-liquid transfer.The response surface analysis method was used to determine air sterilization effect and optimize process parameters.The current study can provide a better choice for solving the problem of microbial contamination in indoor air.更多还原