Methodological bases for designing double-circuit closed air purification systems

Abstract

The article considers the main methodological principles of designing closed double-circuit systems for air purification from polydisperse dust. This cleaning system has a significant advantage compared to its direct-flow counterparts, namely, it allows avoiding emissions of dust not captured in the cleaning apparatus into the atmosphere. This, predominantly fine-grained dust, is captured by repeatedly passing the flow through the catcher of the circulation circuit. That is, the avoidance of environmental pollution is achieved using a new scheme for the movement of a dusty gas stream to be cleaned. The introduction of an innovative flow scheme does not allow the use of traditional calculation methods; therefore, the purpose of the article is to formulate the main methodological approaches to the design of two-loop closed treatment systems. It is shown that the design of a purification system should consist of two main stages. The first is the calculation of the performance indicators of the system elements. It is based on data on the fractional composition of dust (differential distribution curve) and the characteristics of the trapping apparatus and is carried out for the main operating mode of the system (cleaning mode) and the final one (run-out mode). The proposed calculation method, unlike all existing ones, allows obtaining the value of cleaning indicators in dynamics. The second is the hydraulic calculation of the system, consisting of the main and circulation circuits. The calculation is proposed to be carried out by compiling the power balances of each circuit separately and, due to this, it is reasonable to select standard injection equipment for them. The calculation is based on hydraulic indicators, which are determined either by generally accepted hydraulic ratios (reference data), or by the graphs obtained in the course of research and given in the article.