These parameters are typically measured with a 20-L dust explosion apparatus in accordance with ASTM standard (ASTM E 1226).
This paper details an approach for calibrating a new 36-l dust explosion vessel by analyzing the turbulent decay following transient dispersion of dust clouds using computation fluid dynamics (CFD).
This study uses a novel dispersion system in a 36-L dust explosion apparatus to eliminate the mechanical shearing from the outlet valve and investigates its effect on dust particle integrity.
Literature has shown the dispersion system (outlet valve, in particular) in a standard 20-L dust explosion apparatus breaks the dust into smaller particles leading to explosion parameters not necessarily corresponding to the original size.
By modifying the dispersion system and the ignition delay time, and hence the flow field and turbulence intensity during the combustion process, the 20-l dust explosion vessels have been calibrated to give results comparable to the 1-m3 vessel as prescribed in the former standard ISO-61844).
In a previous work, we showed that, in the standard 20 L sphere, the dust injection system does not allow generation of a uniform cloud, but rather high gradients of dust concentration are established.
In this work, subcritical water extraction (SWE) of polyphenols from sage (Salvia officinalis L). herbal dust was optimized by simultaneous maximization of total phenols (TP) and total flavonoids (TF) yields, as well as maximized antioxidant activity, determined by DPPH, ABTS and reducing power assay.
This paper reports on results of computations and measurements to determine the influence of process parameters like the cone rotational speed (6 15 Hz), the reactor volume (3 200 l), the wood-dust feed rate (1 3.5 g s−1) and the reactor temperature (550−700°C) on the product composition.
l mass concentration of dust particles parameter.
The measurements were conducted in a setup which comprises a 5 L explosion chamber, a dust dispersion sub-system, and a transient pressure measurement sub-system.
