【作者】 莫正波；

【导师】 胡松涛；

【作者基本信息】 青岛理工大学 ， 机械设计及理论， 2018， 博士

【摘要】 空气是人类生存必不可少的物质,但空气中病原微生物可以通过呼吸系统进入人体内,从而导致疾病传播。空气消毒是控制室内空气污染和改善室内空气质量的重要手段之一。二氧化氯消毒是在目前使用的空气消毒方法中最理想的一种,它无刺激气味、没有致癌性和致畸性,被联合国世界卫生组织(World Health Organization简称WHO)列为Al级消毒剂。当气体二氧化氯的浓度在美国环保局(U.S.Environmental Protection Agency,EPA)规定的0.1~0.28mg/m~3范围内时,可以在人员不撤离的情况下进行不间断消毒,尤其适合的大型室内公共场所。二氧化氯消毒系统的最终目的,是制备出高纯度的浓度符合要求的二氧化氯空气混合气体。本文在济南市科技局中小企业技术创新基金项目(201403044)与山东省教育厅高等学校科技计划项目(J15LG05)的支持下,围绕制备纯度与浓度符合要求的二氧化氯与空气混合气体这个目的,从理论上对常见结构的二氧化氯发生器建立了物料衡算的数学模型。数学模型中的反应速度及总传质系数等参数,需要通过实验测定。因此文中首先通过实验测定反应速度方程;然后设计安全可靠的二氧化氯消毒系统与设备,以此为基础测定总传质系数,完善数学模型。采用完善后的数学模型,模拟分析气相二氧化氯浓度与最终二氧化氯得率的影响因素,对该套消毒流程的操作条件进行优化,确定出控制方案。采用CFD模拟确定出关键设备气体混合器的结构与参数,并测定了消毒系统的消毒效果。主要研究内容如下:(1)根据化学反应过程的质量守恒和气液传质理论,从理论上建立了常见结构的二氧化氯发生器的物料衡算数学模型。(2)通过对低浓度下亚氯酸钠与盐酸反应生成二氧化氯的实验研究,推导得出低浓度反应液状态下,盐酸与亚氯酸钠反应的动力学方程。分析时间、温度、各反应物浓度及配比等因素对亚氯酸钠转化率的影响。推导的宏观动力学方程为完善数学模型以及后续消毒系统与设备设计及操作提供了理论指导。(3)设计安全可靠的二氧化氯消毒系统以及紧凑的二氧化氯发生器的结构。以此为基础,采用实验测定与迭代计算相结合的方法,推导得出针对该套系统总传质系数的表达式。(4)根据推导的动力学方程和测定的总传质系数表达式,完善二氧化氯发生器物料衡算数学模型。采用完善后的数学模型,对消毒系统操作条件进行正交模拟,分析了气相二氧化氯浓度与最终二氧化氯得率的影响因素,对该套消毒系统的操作条件进行优化,确定出控制方案。(5)确定消毒系统关键设备之一——气体混合器的结构与参数。消毒系统中,二氧化氯与空气混合器是决定气体混合是否均匀的一个重要设备,论文中采用了CFD(计算流体动力学)数值模拟的方法,对气体混合器结构设计进行了优化,选定多孔式文丘里气体混合器;并通过正交实验模拟,确定出混合器的最佳参数。(6)对消毒系统的消毒效果进行实验测定。启用消毒系统,通过实验测定消毒系统的杀菌效果。实验中,杀菌30min,室内空气生物性已经达标。杀菌240min,杀菌率接近90%。实验证明,本文建立的数学模型完全可以用来指导二氧化氯发生和消毒系统的设计与操作。文中设计的二氧化氯消毒装置性能稳定、操作方便、成本低、不产生有害残留,消毒效果良好,能够满足室内空气动态消毒的要求。二氧化氯动态消毒作为一种新兴的空气消毒方法,在空气消毒行业中具有广阔的市场应用前景。更多还原

【Abstract】 Air is essential for human survival.But the pathogenic microorganisms in the air can enter the body by respiratory system,resulting in the spread of disease.Air disinfection is one of the important means to control indoor air pollution and improve indoor air quality.Chlorine dioxide disinfection is the most ideal in currently used methods of air disinfection.It has no stimulating smell,no carcinogenicity and teratogenicity.It is listed as Al level disinfectant by the United Nations World Health Organization(the WHO).When the concentration of chlorine dioxide in EPA(U.S.Environmental Protection Agency)regulations within the range of 0.1~0.28 mg/m~3,continuous sterilization can be conducted with not leaving people.It is especially suitable for large indoor public places.The ultimate goal of chlorine dioxide disinfection dynamic system is to prepare high purity chlorine dioxide and air mixed gas in 0.1~0.28 mg/m~3concentration.This paper is supported by the technology innovation fund for small and medium-sized enterprises of Jinan Technology Bureau and Science(201403044)and Technology Program of Higher Education of Shandong Province Education Department(J15LG05).The mathematic model of material balance is established theoretically for the chlorine dioxide generator of common structure.In the mathematical model,the reaction rate and the mass transfer coefficient are required.Therefore,the reaction rate equation is first determined by experiment.And then a safe and reliable chlorine dioxide disinfection system and compact equipment are designed,as the basis for the determination of the total mass transfer coefficient.The mathematical model is improved.Based on the mathematic model,the influencing factors of the concentration of chlorine dioxide and the yield of chlorine dioxide are analyzed.The operating conditions of the sterilization process are optimized and the control scheme is determined.The structure and parameters of the gas mixer are determined by CFD simulation,and the disinfection effect of the disinfection system is determined.The main research contents of this thesis are as follows:(1)Based on the the mass conservation of chemical reaction and the theory of gas-liquid mass transfer,the mathematical model of material balance of chlorine dioxide generator is established theoretically.(2)According to the experiment research of preparation of chlorine dioxide by sodium chlorite and hydrochloric acid at low concentration,the influence on the rate of sodium chlorite conversion is analyzed about the concentration of reactants,ratio,time and temperature.The reaction dynamics equation is derived according to the experimental data.The macroscopic dynamic equation provides theoretical guidance for the perfection of mathematical model and the design and operation of disinfection system and equipment.(3)A safe and reliable chlorine dioxide disinfection system and a compact structure of generator are designed.According to this system,by combination of experimental determination and MATLAB iterative calculation method,the expression of total mass transfer coefficient formula is derived.(4)The mathematical model is perfected according to the kinetic equation and the expression of total mass transfer coefficient.Factors to the operation of the disinfection system are orthogonally simulated using the mathematical model.Factors affecting the vapor phase concentration of chlorine dioxide and the eventual yield of chlorine dioxide are analyzed.Operating conditions are optimized and the control scheme is determined.(5)The the structure and parameters of the mixer of chlorine dioxide and air is identified.The mixer is an important equipment determining the effect of mixing in the disinfection system.The CFD(computational fluid dynamics)numerical simulation method is used to design the structure and parameters of mixer.Porous type venturi mixer is selected.The best operation parameter of the mixer is determined by means of orthogonal experiment simulation.(6)The effect of sterilization disinfection system is determined through experiment.The disinfection system is enabled and the bactericidal effect of the disinfection system is determined.Indoor air is up to biological standard after 30minutes sterilization.After 240 minutes,sterilization rate is nearly 90%.The mathematical model established in this paper can be used to guide the design and operation of chlorine dioxide preparation and disinfection system.This dynamic disinfection equipment is stable,convenient,low cost and it does not produce harmful residues.Its disinfection effect is good and it can meet the requirements of modern dynamic disinfection.The chlorine dioxide dynamic disinfection as a new air disinfection method,should have a broad market prospect in the air disinfection industry.更多还原