Fundamental mechanisms of soluble dust cake components penetration through gas cleaning filter media

可溶性尘饼成分渗透气体净化过滤介质的基本机制

• 批准号: 406085079
• 负责人: Professor Dr.-Ing. Achim Dittler
• 金额: --
• 依托单位: Arbeitsgruppe Gas-Partikel-Systeme (GPS)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/406085079?language=en
• 关键词: Fundamental; mechanisms; soluble; dust; cake

The quality of dust separation during gas cleaning processes by surface filters is strongly dominated by the particle structures on the filter medium, the filter cake. While research concerning the filtration of inert particles has already lead to major reductions in emissions and energy consumption by these processes, the fundamental mechanisms taking place during the filtration in a non-ideal system, such as dust filtration in the presence of soluble particles and liquid aerosol are still unknown. Within the framework of this project, the fundamental mechanisms of the penetration of soluble dust cake components through surface filters during gas cleaning are being investigated. In the first project phase, a suitable material system was identified, methods to analyze the filters were studied and tested and experiments concerning the influence of short-term exposure of soluble filter cakes to water droplets were carried out. Therefore, the first phase of the penetration of the salt particles, the uptake of liquid and rearrangement of the soluble particles on the filter surface, and its effect on the operating behavior (pressure drop) of the filter was investigated. The focus of this new phase of the project, building on the present results, will be the investigation of the influence of the operating mode during the exposure to water droplets and the influence of the composition of the filter cake of soluble and insoluble particles on the penetration. Therefore it will be systematically investigated, which effect an intermittently exposure to water droplets compared to a continuous exposure has. Additionally it will be analyzed how the penetration of the salt depends on the proportion of soluble and insoluble particles in the originally dry filter cake. For a detailed analysis of the filter, a camera system observing the filter upstream and downstream simultaneously is implemented to observe the dissolving and rearranging of the particles and the film formation drainage of the solution and correlate it to the observed operating behavior (pressure drop, drainage). Furthermore, during the final phase of the project, the limit of the observations, and conclusions will be examined, by investigating the penetration of salt through filters with very different structural parameters (depth filtration). Therefore, also the applicability of already existing models such as the jump-and-channel-model from oil-mist filtration applications will be examined. At the end of this second project phase it will be clear, which mechanisms determine the penetration of soluble particles through filter media and how they depending on the operating mode, the proportion of soluble particles in the filter cake and the structure of the filter affect the operating behavior of the filter (pressure drop, draunage, separation efficiency).

表面过滤器在气体净化过程中的粉尘分离质量主要取决于滤料上的颗粒结构，即滤饼。虽然有关惰性颗粒过滤的研究已经大大减少了这些过程的排放和能源消耗，但在非理想系统中过滤过程中发生的基本机制仍不清楚，例如在存在可溶颗粒和液体气溶胶的情况下过滤粉尘。在该项目的框架内，正在研究气体净化过程中可溶粉饼组分通过表面过滤器渗透的基本机制。在第一个项目阶段，确定了合适的材料体系，研究和测试了过滤器的分析方法，并进行了短期接触可溶性滤饼对水滴影响的实验。为此，研究了盐粒渗透的第一阶段、液体的吸收和可溶颗粒在过滤器表面的重排及其对过滤器运行行为(压降)的影响。在现有成果的基础上，这一新阶段项目的重点将是调查暴露在水滴中的运行模式的影响，以及可溶和不可溶颗粒的滤饼组成对渗透的影响。因此，将对其进行系统研究，与连续暴露相比，间歇暴露在水滴中会产生什么影响。此外，还将分析盐的渗透率如何取决于最初干燥的滤饼中可溶和不溶颗粒的比例。为了对过滤器进行详细的分析，安装了一个摄像系统，同时观察过滤器上下游的情况，以观察溶液中颗粒的溶解和重新排列以及成膜排放，并将其与观察到的操作行为(压降、排放)相关联。此外，在项目的最后阶段，将通过调查盐通过具有非常不同的结构参数的过滤器(深度过滤)的渗透来检查观察的限度和结论。因此，还将审查现有模型的适用性，例如来自油雾过滤应用的跳跃和通道模型。在第二个项目阶段结束时，将清楚哪些机制决定了可溶颗粒通过过滤介质的渗透，以及它们如何取决于运行模式、滤饼中可溶颗粒的比例和过滤器的结构影响过滤器的运行行为(压降、排水量、分离效率)。