The present study focuses on use of hydrodynamic cavitation (HC) alone and in combination with oxidants as pre-treatment for conventional biological treatment with an objective of enhancing the treatability of industrial effluent. Under fixed conditions of inlet pressure (4 bar) and pH (4), chemical oxygen demand (COD) reduction has been investigated using HC alone and its combination with hydrogen peroxide (H₂O₂), O₃ and Fenton’s reagent. The individual operation of HC resulted in only 21.6% of reduction in 120 min of treatment with rate constant of 2.1 ×10^-3 min^-1. The combination of HC+H₂O₂, HC+O₃ and HC+Fenton yielded significantly enhanced COD reduction than the treatment using HC alone with actual values as 39.5%, 52.8%, and 72.1% respectively. Improvements in primary and tertiary treatment options have also been investigated in the current work. The coagulation using alum as primary treatment to HC+Fenton process gave overall enhanced COD reduction of about 80%. Subsequent conventional biological oxidation resulted in COD reduction of about 98%. Finally, the effluent obtained from biological treatment was filtered to remove biomass and disinfected using sodium hypochlorite. After all the steps of treatment, the final COD obtained was ≤ 250 mgO₂/dm³ which is suitable for discharge. Also, different treatment approaches were compared based on the power consumption and the operational cost. Overall, an improved treatment scheme involving HC+Fenton conventional biological treatment and chemical oxidants was demonstrated for treatment showing compliance for the treated effluent.

本研究的重点是单独使用流体动力空化（HC）并与氧化剂结合使用作为常规生物处理的预处理，目的是提高工业废水的可处理性。在固定的入口压力（4 bar）和pH（4）的条件下，仅使用HC及其与过氧化氢（H ₂ O ₂），O ₃和Fenton试剂的组合，就研究了化学需氧量（COD）的降低。HC的单独操作在治疗120分钟内仅减少21.6％，速率常数为2.1×10 ^-3 min ^-1。HC + H ₂ O ₂，HC + O _3的组合与单独使用HC的处理相比，HC + Fenton和HC + Fenton的COD降低效果显着提高，实际值分别为39.5％，52.8％和72.1％。在目前的工作中，还研究了一级和三级治疗方案的改进。使用明矾作为HC + Fenton工艺的主要处理方法进行的混凝处理总体上使COD降低了约80％。随后的常规生物氧化导致COD降低约98％。最后，将从生物处理中获得的废水过滤以除去生物质，并使用次氯酸钠消毒。经过所有处理步骤后，最终获得的COD≤250 mgO ₂ / dm ³适合放电。此外，根据功耗和运营成本比较了不同的处理方法。总体而言，已证明涉及HC + Fenton常规生物处理和化学氧化剂的改进处理方案可显示出对所处理废水的依从性。