As an advanced oxidation process, hydrodynamic cavitation generates radicals inducing reduction of chemicals in water. In the present work dye degradation is investigated as a representative for such chemical. Cavitation intensity, outgassing and flow reactivity largely depend on pressure boundary conditions. The paper presents an experimental study aimed to investigate effects of outgassing on degradation through jet cavitation in a multiphase reactor by varying back pressure between 0.6 and 2 bar at a constant pressure difference of 40 bar. The measurements reveal that some outgassed air bubbles are recirculated into the jet, which may enhance the process as an oxidizing agent. Degradation is found to vary significantly by back pressure obtaining maximum degradation around ambient pressure in the experimental setup used. But outgassing also restricts reactivity at back pressures below ambient pressure. The influence of outgassing on degradation unlocks opportunities for energy-to-degradation efficient applications.

中文翻译：

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除气对射流空化中染料降解的影响


作为一种高级氧化过程，流体动力学空化会产生自由基，诱导水中化学物质的还原。在本工作中，染料降解作为此类化学品的代表进行了研究。空化强度、脱气和流动反应性在很大程度上取决于压力边界条件。本文提出了一项实验研究，旨在通过在 40 bar 的恒定压差下在 0.6 和 2 bar 之间改变背压来研究脱气对多相反应器中射流空化降解的影响。测量显示，一些脱气的气泡再循环到射流中，这可能会增强作为氧化剂的过程。发现降解会因背压而发生显著变化，在所使用的实验设置中，在环境压力附近获得最大降解。但释气也会限制在低于环境压力的背压下的反应性。释气对降解的影响为能量降解高效应用提供了机会。