Prevention of Accidental Pollution With Combustion Gases After the Occurrence of Explosions

Abstract

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.

Considerations regarding the specific tests applicable to electric motors with type of protection flameproof enclosure „d” and type of protection increased safety

“…No ignition of the explosive test mixture shall occur [4]. [9][10][11], as exemplified in Figure 1. To carry out these tests were used specific testing equipment like: Oxygen analyser SERVOMEX 2200, Baker surge tester D12R, PP24 -impulse generator.…”

“…The purge gas supply is provided by the user, from a fixed supply or from portable gas bottles. (Nitrogen is sometimes used instead of using clean air) [9].…”

“…Ignition risks owing to stator sparking may also occur when the motor is running; this phenomenon has only been acknowledged relatively recently. Note that pre-start purge does not offer any protection, but suitable special measure might be to pressurise the motor enclosure continuously in order to prevent the ingress of a potentially flammable atmosphere; this arrangement should be interlocked with pre-start and post shut-down timers and pressure/flow measurement, but may not fully comply with the standard for Ex p apparatus [9].…”

The test method used to determine surface temperature for Ex equipment certification

“…Basic principles of prevention and protection against explosion are: -prevention: avoid or reduce explosive atmospheres and avoiding all possible sources of ignition; -protection: stopping the explosion and/or limiting the effects of an explosion, through protection measures, for instance through isolation, suppression and explosion resistant constructions [2].…”

Research on the advantages of in situ investigation of air quality parameters by means of environmental auto laboratories

“…Of particular importance is the precise or clear knowledge of the investigation's purpose. Generally speaking, an environmental analysis considers the following objectives [2,3,4]:…”