Modern tendencies in the development of dust collecting theory and practice

Abstract

Trends in the development of dust collecting technology are indicated. Classification is submitted for dust collectors based on the predominant deposition mechanism in each specific type of equipment. Accumulated data are summarized for the dependence of particle size (d 50 ) collected with an efficiency of 0.5 on energy consumption in different inertial equipment. The future for the use of modular type ceramic filters is noted.Solution of the problem of cleaning industrial gases and aspirated air from suspended particles (dust) occupies an important place in the provision of ecological accident prevention both in production processes and ventilation systems. However, the list of forms of dust collecting equipment used in practice in recent years has not undergone marked changes, and this is explained by the lack of new practically proven technical solutions for providing deposition mechanisms used in dust collectors. Individual attempts have been made to combine the electrostatic mechanism for depositing suspended particles with inertial deposition (for example in electrocyclones, electrostatic scrubbers) and with mechanisms used during filtration, but there has not been extensive use of these solutions in industry [1].Recently, the development of dust collection technology has moved in the direction of optimizing existing solutions: development of quite simple and reliable methods for engineering design of dust collectors and use of new promising materials within the structures of equipment.The first trend of work in the development of dust collection is connected with analyzing the inertia mechanism of depositing dust particles (in dry and wet centrifugal dust collectors, scrubbers, high velocity mist collectors) [2] and the mechanism of depositing dust particles as a result of electrostatic forces ( in electric filters) [3,4].Work on the application of new materials has undergone the greatest development for filtration equipment (materials for filtration barriers) and electric filters (polymer electric filters) [5].Theoretical developments in the field of dust collection make it possible to resolve such an important question for any technology as the classification of dust collectors. The classification of dust collectors presented in publications [6-8] has been based on different principles for each group of equipment. Wet dust collectors (scrubbers) have been separated into forms depending on the shape of the deposition surface for captured particles (droplet, film, bubble), filters have been separated according to the type of filtration barrier used (fiber, cloth, granular), and electrostatic precipitators have been separated according to the method for regenerating the deposition surface and the direction of movement of the gas stream (dry, wet, horizontal, vertical).Today taking account of accumulated information there is the possibility of proposing the classification of dust collectors ( Fig. 1) based exclusively on the predominant deposition mechanism in each type of equipment.