Pneumatic loading methods

Volume of vessel (free volume V) Shape of vessel (area and aspect ratio) Type of dust cloud distribution (ISO method/pneumatic-loading method) Dust explosihility characteristics Maximum explosion overpressure P ax Maximum explosion constant K ax Minimum ignition temperature MIT Type of explosion suppressant and its suppression efficiency Type of HRD suppressors number and free volume of HRD suppressors and the outlet diameter and valve opening time Suppressant charge and propelling agent pressure Fittings elbow and/or stub pipe and type of nozzle Type of explosion detector(s) dynamic or threshold pressure, UV or IR radiation, effective system activation overpressure Hardware deployment location of HRD suppressor(s) on vessel... 

There was no significant damage to equipment in the fire tests, and it was demonstrated that a Jet Airmix mixer may safely handle the mixing of RP formulations on a routine basis. Since a high risk of fire is always associated with any method of transfer of RP, a pneumatic conveying system [dynamic air, two phase positive pressure transfer system was evaluated to load RP into the Jet Airmix mixer. Electrostatic charge measurements were minimal and indicated the system was satisfactory to load the blender. 

Although the results from these methods may correlate to some extent, they simulate different essential requirements of the catalysts. Attrition loss primarily relates to handling, transport, loading and screening whereas the crush tests simulate the forces imposed on the catalyst in a fixed bed. The drop test simulates the risk of catalyst break-up during loading and pneumatic transport. 

The most common introduction of the samples in this source consists of a pneumatic nebulizer which is driven by the same flow of argon which carries the resulting droplets in the plasma. An ultrasonic nebulizer and heated desolvation tube are also used because they allow a better droplet size distribution which increases the load of sample into the plasma. Generally, the sample solutions are continuously introduced in the nebulizer at the rate of about 1 ml min-1 with the help of a peristaltic pump. However, this is not acceptable with small-sample solutions. Therefore an alternative method using the flow injection technique is employed to introduce a small sample of about 100 pi. The sample solution is injected into a reference blank flow so that the sample is transported in the nebulizer and a transitory signal is observed. 

The spans depend on various factors, like construction method (mechanically or pneumatically pre-stressed), construction type (one-layer or multilayer systems), ground plan geometry, thickness of foil, load value and load history, and quality of foil and welding seams. Therefore, the following spans display only reference values. 

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