This paper aims to study the behavior of air-gas explosion systems, in terms of propagation speed of pressure wave and flame front, based on experimental measurements in a shock tube, in order to prevent accidental pollution with the combustion gases. The characteristic parameters of the explosion process determined using the shock tube, the velocity of propagation of the flame front, the speed of propagation of the wave of pressure, explosion pressure at various distances from the source of initiation, can be used in the preparation of explosion risk assessment studies for technological processes carried out in potentially explosive atmospheres. Taking the developed technical measures would make possible ensure both the explosion protection and the prevention of accidental pollution with combustion gases.
Carcasses of electrical or non-electrical equipment operating in potentially explosive atmospheres must provide a certain degree of protection against access to hazardous parts, penetration of solid bodies and/or water penetration, which must be tested according to the specifications of the Ex protection types. Normal protection classes are indicated by the international IP code followed by two characteristic digits referring to the protection against penetration of solid foreign bodies and water protection, followed by optional letters if required by the beneficiary according to the imposed conditions of use. Within the ENExEMEIP laboratory, have been developed laboratory tests to verify the first characteristic figure of the standard degree of protection according to the standardized European method. In the paper is presented the test stand of the large gauge equipment, a stand made with state-of-the-art equipment that provides the necessary performance for the accreditation of the test according to the standardized requirements. Checking dustproof protection to equipment used in areas where explosive atmospheres generated by combustion dust may occur is particularly important for assessing compliance with the requirements of the ATEX Directive [5], as this protection is a basic requirement for explosion protection.
In industrial sectors that use, process, transport or store, substances such as combustible dusts could exist some workplaces with explosion hazard due to the possibility of dust/air explosive formation and ignition, both inside the installations and in the surrounding atmosphere. Methods and means of protection aim to prevent the development of explosive atmospheres, followed by preventing the occurrence of ignition sources and then limiting the effects of explosions. To assess the risk of ignition of the explosive atmosphere, there must be known first of all, the explosive atmosphere’s sensitivity to ignition by electrostatic discharge, respectively, the minimum ignition energy of the explosive mixture, afterwards being required an analysis on the possibilities of formation and discharge of electrostatic charge. For the most common combustible dusts, the minimum ignition energy is given, but for new types of flammable substances this parameter defining the sensitivity to ignition of the mixture by electrostatic discharges must be determined. The paper presents the results of research carried out in order to develop the methods and standards for determining the minimum ignition energy of the combustible dust / air mixture and of the methods for the assessment of the risk of ignition of the dust/air explosive atmosphere by electrostatic discharge.
Many industrial processes involving the presence of dust and combustible dust, suspended or accumulated in the form of deposits, have the potential to lead to a fire, explosion or decomposition in the presence of oxygen. As the damage caused by an explosion of dust is generally greater than that caused by explosions of flammable gases and vapours, a special attention must be paid to measures and means of protection and prevention of explosions of dust. A dust explosion can only occur if there is mainly a potentially explosive atmosphere generated by the air / dust mixture and a source of ignition. The level of safety is given by the operational efficiency of the employees and technical equipment involved in the production process to ensure that at least one of the above conditions is eliminated. The probability of a dust explosion is related to the physicochemical properties of the processed materials, together with the nature of the operations performed and the equipment used. This paper highlights the principles and factors that must be taken into account when conducting an explosion risk assessment in installations with combustible dust atmospheres in order to establish prevention and protection measures, with the aim of ensuring a tolerable level of risk.
Many processes involving dusts, suspended or accumulated, have the potential to lead to fire, explosion or decomposition in the presence of oxygen and an ignition source. The risk of dust explosions increases as more and more products take the form of dusts or require the use of dusts during manufacture. In spite of extensive research and development to prevent and mitigate dust explosions in the process industries, this phenomenon continues to represent a constant hazard to industries including manufacturing, using and handling of combustible dust material. The purpose of explosion preventing and protection measures is to prevent explosion occurrence, by eliminating or avoiding the conditions leading to explosions. The dust explosion and combustion characteristics are required to be known, in order to suitably choose and draw up the preventive and protection measures. Once known, the protection/prevention measures can be correlated with the safety characteristics. The aim of this paper is to analyze of explosion and combustion characteristics of wood dust clouds in dependence of the particle size distribution. The paper shows the importance of knowing the explosive characteristics of dusts and identifying the factors of influence in obtaining the results.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.