单区式双涡旋型极板电除尘器的电场仿真研究

发布时间：2018-03-14 06:41

本文选题：电除尘器　切入点：单区双涡旋型　出处：《江苏大学》2015年硕士论文　论文类型：学位论文

【摘要】：我国能源结构以煤为主,燃煤引发的粉尘和酸雨危害严重。其中,粉尘不仅自身是一种污染物,它又是携带重金属、多环芳烃等有毒物质的载体。较小的粉尘颗粒能够悬浮在空气中,给人身健康、环境、社会带来不利的影响,成为我国大气环境安全较大的威胁之一。电除尘器由于具有烟气处理量大、除尘捕集效率高、材料耐性好、无二次污染等突出优点,适用于多数的民用设施和部门。但传统电除尘器技术已经无法满足不断提高的大气环境保护要求,尤其是对微细粉尘的捕集,对粒径小于2.5μm的超微细颗粒(PM2.5)的捕集效率通常低于90%。因此,必须研究更先进的电除尘技术来满足社会和市场需要。以单区式双涡旋型极板电除尘器为研究对象,该电除尘器的特点在于：一是通过气流提高离子动量,降低离子合并率,从而提高离子浓度,增加粒子荷电量；二是涡旋型收尘极板结构的设计使气流在收尘极板涡旋处形成旋涡,延长粉尘停留时间,增加超微细粉尘与离子的碰撞机率和凝并效率,进而提高对微细粉尘的捕集效率。本文在传统电除尘的理论基础上,阐述了单区式双涡旋型极板电除尘器的除尘机理,通过分析,给出以离子浓度作为评价单区式双涡旋型极板电除尘器电场性能的指标的依据。通过建立单区式双涡旋型极板电除尘器的几何模型,并结合电流连续方程、泊松方程、拉普拉斯方程等对电场强度的有限元进行分析。运用ANSYS WORKBENCH模拟软件对电除尘器内部电场和电势分布进行数值模拟,通过改变电压U、电极直径D、排间距L、极板高度H这四项参数,来模拟对电场和电势的影响。模拟结果表明,电压U增加,电场强度增加,电极直径D=lmm,排间距L=120mm,极板高度H=10mm时,电场强度分布效果较好。通过离子浓度实验对模拟结果验证,考察在风速恒定为2.03m/s的情况下,不同电压u、电极直径D、排间距L、极板高度H对离子浓度的影响规律,并确定在U=-18kV, D=1mm, L=120mm, H=10mm时得出电场性能较好的电极配置参数,此时离子浓度可高达6.11×109cm-3,并通过正交实验确定外加电压是影响收尘区电场强度的主要因素之一.
[Abstract]:The energy structure of our country is dominated by coal, and the dust and acid rain caused by coal burning are serious. Among them, dust is not only a pollutant itself, but also carries heavy metals. A carrier of toxic substances such as polycyclic aromatic hydrocarbons. Smaller dust particles can be suspended in the air, causing adverse effects on human health, the environment, and society. Electrostatic precipitator has many outstanding advantages, such as large amount of flue gas treatment, high dust collection efficiency, good material endurance, no secondary pollution, etc. Suitable for most civilian facilities and sectors. But the traditional ESP technology can no longer meet the increasing requirements for the protection of the atmospheric environment, especially the capture of fine dust, For ultrafine particle size less than 2.5 渭 m, the capture efficiency of PM2.5 is usually less than 90. Therefore, it is necessary to study more advanced electrostatic precipitators to meet the needs of society and market. The characteristics of the electrostatic precipitator are as follows: first, increasing ion momentum through air flow, reducing ion combination rate, thus increasing ion concentration and increasing particle charge; The second is the design of vortex dust collector plate structure, which makes the vortex form at the vortex of dust collecting plate, prolongs the residence time of dust, increases the probability of collision between ultrafine dust and ions and the efficiency of condensation. In this paper, based on the theory of traditional electrostatic precipitator, the dust removal mechanism of single zone double vortex plate electrostatic precipitator is discussed. Using ion concentration as the basis for evaluating electric field performance of single zone double vortex plate electrostatic precipitator, the geometric model of single zone double vortex plate electrostatic precipitator is established, combined with current continuity equation and Poisson equation. The finite element analysis of electric field intensity is carried out by Laplace equation. The electric field and potential distribution in electrostatic precipitator are simulated by using ANSYS WORKBENCH software. By changing voltage U, electrode diameter D, row distance L, electrode height H, four parameters are obtained, such as voltage U, electrode diameter D, row distance L, electrode height H, etc. The simulation results show that the electric field intensity distribution is better when the voltage U increases, the electric field intensity increases, the electrode diameter is Dlmm, the distance between rows is 120 mm, the electrode height is 10 mm, and the ion concentration experiment is used to verify the distribution of electric field intensity. Under the condition of constant wind speed of 2.03 m / s, the effects of different voltage u, electrode diameter D, row spacing L and plate height H on the ion concentration were investigated. The electrode configuration parameters with good electric field performance were obtained at U-18kV, D1 mm, L20 mm, H10 mm. The ion concentration can be as high as 6.11 脳 10 ~ (9) cm ~ (-3), and the applied voltage is one of the main factors affecting the electric field intensity in the dust collecting area.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X701.2

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