Conditions Optimization And Effect Evaluation Of Inhibition On Explosion Of Flammable Liquid Vapor By Dry Chemical Powder

Currently, the vast majority of dry powder explosion suppression technology research isrelated to gas and coal dust explosion, and the explosion suppression experiments of gasoline,kerosene and other flammable liquid vapor are also rare. In order to prevent the explosion offlammable liquid vapor, for, this paper carry out a series of explosion suppression experimentsof93#gasoline, aviation kerosene using four kinds of inhibitors, ABC dry powder(NH4H2PO4), ABC ultrafine powder (NH4H2PO4), BC dry powder (NaHCO3), APP ultrafinepowder ((NH4PO3)n), and analysis the rule of powder flammable liquid vapor explosionsuppression. The main contents and results are as follows:(1) A self-designed test system of flammable liquid vapor blasting, explosion suppressioncharacteristics, and the translation of the experimental conditions of gasoline vapor, aviationkerosene vapor to corresponding liquid volume respectively:11.2-51.7mL and5.55-34.2mL;optimized design four key technology of test system, including: combustible liquid thermalvolatilization ejector technology, compressors and vacuum pumps gas collaborationtechnology, unilateral electrode center ignition technology, outside the trigger of delay circuit.(2) Summarized the12individual indicators which were used in the experiments of fourdry inhibitors, looked into some important parameters of explosion suppression material, suchas chemical composition, particle size, density, anti-caking resistance and fire performanceand so on; analyzed comparatively black powder and single base propellant powder pressurecurve and determined the black powder as a gas tank explosion suppression agent; analyzedcomparatively the large flow of small droplets spray nozzle angle and wide-angle solid conenozzle SMP from powder spraying Angle, fogging shape, Dispersion evenness, coverage areaand other parameters to determine a large flow nozzle droplet spray nozzle as the explosion suppression tank nozzle.(3) Through a blank experiment, the explosion pressure curves was measured at differentconcentrations of93gasoline, aviation kerosene vapor selecting the oil28mL,25mLexplosion pressure as a standard curve. It has shown that: what was corresponding to28mLgasoline is vapor concentration is3.25%, explosion relaxation time is52ms, the peak pressureof time is150ms, the maximum boost rate is37.2mv/ms, peak pressure output voltage is2125mv, calibration pressure value is0.90MPa, explosive energy is4.29×105mv·ms; whatwas corresponding to25mL aviation kerosene is vapor concentration is2.70%, the relaxationtime of the explosion is44ms, time to reach peak pressure is133ms, the maximum boost rateis31.6mv/ms, peak pressure output voltage is1844mv, calibrated pressure is0.78MPa, theexplosive energy is3.48×105mv·ms.(4) Through comparing and analyzing the explosion pressure curve of different drypowder inhibit flammable liquid vapors, it was determined that the optimal delay time of theABC powder, BC powder, ABC ultrafine powder, APP ultrafine powder explosionsuppression experiments were15ms,20ms,50ms and more than150ms respectively, thelargest explosion suppression peak pressure decrease were48.5%,29.4%,57.4%and22.1%respectively, and greatest decline of explosive energy of ABC powder,BC powder, ABCultrafine powder were40.6%,34.0%and42.0%. The relationship between the inhibitingeffect of ABC powder, BC powder, ABC superfine powder and the powder concentration isthat the performance of the three powder were weakened inhibition (40-80g), basicallyunchanged (40-120g) and inhibition enhanced (40-120g) with the increase of concentration ofpowder; Finally, summarized the important research results and formulated powder explosionsuppression effect rating scale, and made practical recommendations in accordance with thedirection of the explosion suppression characteristics of the four dry powder.