Safely explosive limits

Tables 16 and 17 Hst tke analytical test methods for different properties of interest. The Manufacturing Chemists Association, Inc. (MCA) has pubUshed the Chemical Safety Data Sheet SD 63, which describes in detail procedures for safe handling of use of toluene (46). The Interstate Commerce Commission classifies toluene as a flammable Hquid. Accordingly, it must be packaged in authorized containers, and shipping must comply with ICC regulations. Properties related to safe handling are autoignition temperature, 536°C explosive limits, 1.27—7.0 vol % in air and flash point 4.4°C, closed cup.

Explosion testing should be performed to establish safe operating limits. Dust explosibility and ignitability are measurements of the potential for a combustible material, in dust form, to explode or ignite. Any combustible material has the potential to cause a dust explosion if dispersed in air as a dust and ignited. Further details on explosibility testing can be found in Palmer (1973), Bartknecht (1989) and Eckhoff (1997). 

GP 3] ]R 3h] [R 4a] Safe operation in the explosive regime was demonstrated [103]. Catalytic runs with 1-butene concentrations up to 10 times higher than the explosion limit were performed (5-15% 1-butene in air 0.1 MPa 400 °C). A slight catalyst deactivation, possibly due to catalyst active center blockage by adsorption, was observed under these conditions and not found for lower 1-butene concentrations. Regeneration of the catalyst is possible by oxidation. 

GP 11] [R 19] An impressive example of the impact of miniaturization on the explosion limit is given in [9], For a conventional reactor of 1 m diameter, explosive behavior sets in at 420 °C at ambient pressure (10 Pa). In turn, an explosion occurs at about 750 °C when the reactor diameter is decreased to about 1 mm. A further reduction to 100 pm shifts the explosive regime further to higher pressures and temperatures. Even the first explosion limit is above ambient pressure. Now, explosive behavior can be excluded and so the reaction becomes inherently safe. 

Octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine or cyclotetramethylene tetranit-ramine (HMX) with a m.p. of 291 °C, is also regarded as a heat-resistant explosive in some countries [32, 33] and its safe working limit is 225 °C. 

Flash point, -90°C explosive limits, 0.9-98% auto-ignition temperature, 38-52°C (lowered by moisture).2 Extinguish from a safe distance with water or liquid nitrogen. Do not use halocarbons.3... 

A fundamental solution to the dust explosion problem is to use a wet process so that dust suspensions do not occur at all. If a wet process can be used, it is one of the most satisfactory methods. However, the process must be wet enough to be effective. Some dusts with a high moisture content can still ignite. Dust concentrations in major equipment can be designed below the lower flammable limit, but this often cannot be counted on in operation. Dust concentrations cannot be safely designed to be above an upper flammable limit, because such a limit is ill-defined (Lees, 1980). For a large number of flammable dusts, the lower explosion limit lies between 20 and 60 g/m3. The... 

USEBLASTING - Comparable to 40% ammonia dynamite. High toxic fume production of this explosive limits its use to one where prevalent winds can cany these toxic fumes in a safe direction, away from the user. 

Approximately 25 kg/s of vapor are released to the atmosphere. The lower explosive limit CL for the vapor is 0.010 m3 vapor/m air. The vapor density of the vapor is 2 kg/m3. If the wind speed Uv is 3 m/s, what is the distance d required for safe disposal of the vapor in the air as evaluated from the relation... 

Microreactors, due to the high wall-to-volume ratio and the absence of runaway, allow to safe operation within the explosion limits [179], thus enabling an increase in process productivity. A relevant case is the direct synthesis ofhydrogen peroxide [180], for which... 

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