Research On Filtering Characteristics Of The Venturi Scrubber

Venturi scrubbers have been widely used in the flue gas desulphurization and dustremoval with high removal efficiency and low maintenance, etc. However, the operations ofindustrial venturi scrubbers rely on external power, so it was unsuitable as a mitigation facilityfor severe accident in nuclear power plant. Self-priming venturi scrubber working at thesubmerged state and the washing fluid is injected relying on the static pressure differencebetween inside and outside of the throat. The injection was automatically changed accordingto the gas ejector, so the circulating pump could be saved and the complexity of the systemcould be reduced, that the accident would be processed using completely passive technology.While the self-priming venturi scrubber was running, the inside of which was themixture of steam and air with radioactive and the outer was the specific washing liquid withcertain chemical composition. The washing liquid was injected into the throat of the scrubber,and the radioactive substances were remained in the washing solution through wetting andchemical reaction. In this paper, the atmosphere environment of the containment at severeaccident was simulated, and the entrainment properties, resistance characteristics, the internalflow and filtration properties of the self-priming venturi scrubber was experimental study,obtained the following results:(1) In this paper, the pressure drop formula of the self-priming venturi scrubber wasfitted based on experimental data and the average relative error of the formula is less than±15%, most of the which within±10%.(2) While the liquid level was remained at certain circumstance, the particle removalefficiency has a more significant increase with the improvement of gas flow rate of throatinitially, and when the speed of the throat reaches to a certain level, the collection efficiencyimproved to a lesser extent; the amount of washing liquid ejector will be increased with theimprovement of the submerged depth, at the same time, the pressure loss will be increasedtoo, as long as the submerged depth is no less than45cm, the collection efficiency can reach99%.(3) The iodine concentration on iodine removal efficiency is not obvious, which will beimproved with the increase of flow rate and the inundation depth of throat; in order to ensure a stable performance in iodine removal, the submerged depth of the throat should not be lessthan60cm, and the iodine removal efficiency was up to99.8%.