Abstract:
Wastewater decontamination in pharmaceuticals is crucial to prevent environmental and health risks from API residues and other contaminants. Advanced oxidation processes (AOPs) combined with cavitational treatments offer effective solutions. Challenges include designing reactors on a large scale and monitoring the effectiveness and synergies of the hybrid technology. In the present work, pilot-scale treatment of a real high COD (485 g/L) pharmaceutical wastewater (PW) was investigated using hydrodynamic cavitation (HC) operated individually at 330 L/h or in combination with oxidants and electrical discharge (ED) with cold plasma (15 kV and 48 kHz). The first approach consisted of PW cavitational treatment alone of 7 L of 1:100 diluted PW at a HC-induced pressure of 60 bar and a flow rate of 330 L/h. However, this strategy did not provide satisfactory results for COD (∼15% less), and only when HC treatment was extended to more than 30 min in a recirculation mode, encouraging results were obtained (∼45% COD reduction). Consequently, a hybrid approach combining HC with ED-cold plasma was chosen to treat this high-COD PW. Aiming to establish an efficient flow-through hybrid process, after optimising all cavitation and electrical discharge parameters (45 bar HC pressure and 10 kHz ED frequency), the best COD abatement of ∼50 % was recorded with a 1:50 diluted PW. However, a subsequent adsorption step over activated carbon was required to achieve an almost quantitative COD reduction (95%+). Our integrated physicochemical process proved to be extremely efficient in treating high-COD industrial wastewater and resulted in a remarkable reduction of the COD value. In addition, the residual surfactants content in the PW were also drastically reduced (98%+) when a small amount of oxidants was added in the hybrid HC/ED treatment.
摘要:
药品中的废水净化对于防止API残留物和其他污染物的环境和健康风险至关重要。高级氧化工艺(AOPs)与空化处理相结合提供了有效的解决方案。挑战包括大规模设计反应堆和监测混合技术的有效性和协同作用。在目前的工作中,使用水力空化(HC)在330L/h下单独运行或与氧化剂和冷等离子体放电(ED)结合使用(15kV和48kHz),研究了实际高COD(485g/L)制药废水(PW)的中试处理。第一种方法包括在HC诱导的60巴压力和330升/小时的流速下,仅对7升1:100稀释的PW进行PW空化处理。然而,这一策略对COD没有提供令人满意的结果(~15%以下),并且仅在再循环模式下将HC处理延长至30分钟以上时,获得了令人鼓舞的结果(COD降低45%)。因此,选择将HC与ED冷等离子体结合的混合方法来处理这种高CODPW。旨在建立高效的流通混合工艺,在优化所有空化和放电参数(45barHC压力和10kHzED频率)之后,用50稀释的PW中的1记录到最佳的化学需氧量降低50%。然而,需要在活性炭上的后续吸附步骤以实现几乎定量的COD降低(95%+)。事实证明,我们的综合物理化学工艺在处理高COD工业废水方面非常有效,并显着降低了COD值。此外,当在混合HC/ED处理中加入少量氧化剂时,PW中的残余表面活性剂含量也显著降低(98%+)。