Galoppo Simona, Fenti Angelo, Falco Giovanni, Huang Qingguo, Chianese Simeone, Musmarra Dino, Iovino Pasquale
Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031, Aversa, Italy.
Department of Environmental, Biological and Pharmaceutical Science and Technologies, University of Campania "Luigi Vanvitelli", Via Vivaldi 43, 81100, Caserta, Italy.
Heliyon. 2024 Aug 23;10(17):e36803. doi: 10.1016/j.heliyon.2024.e36803. eCollection 2024 Sep 15.
Wastewater from livestock farms contains high concentrations of suspended solids, organic contaminants, and nitrogen compounds, such as ammoniacal nitrogen. Discharging livestock effluents into water bodies without appropriate treatment leads to severe environmental pollution. Compared to conventional treatment methods, electrochemical oxidation exhibits higher nitrogen removal efficiencies. In the present work, the electrochemical removal of ammoniacal nitrogen from real livestock wastewater was investigated through a lab-scale reactor. Preliminary experiments were carried out to investigate the effects of different anode materials, including boron-doped diamond and iridium/ruthenium-coated titanium, on the total nitrogen removal efficiency using synthetic wastewater. Boron-doped diamond, a well-known non-active electrode, allowed to obtain 63.7 ± 1.21 % of total nitrogen degradation efficiency. However, the iridium/ruthenium-coated titanium electrode, belonging to the class of active anodes, showed a higher performance, achieving 78.8 ± 0.76 % contaminant degradation. Coupling iridium/ruthenium-coated titanium anode with a stainless-steel cathode improved the performance of the system, achieving even 96.2 ± 2.73 % of total nitrogen removal. The optimized cell configuration was used to treat livestock wastewater, resulting in the degradation of 67.0 ± 2.25 % of total nitrogen and 37.3 ± 0.68 % of total organic carbon when sodium chloride was added. At the end of the process, the ammonium content was completely removed, and only 17.7 ± 0.51 % of the initial nitrogen turned into nitrate. The results show that the proposed system is a promising approach to treating livestock wastewater by coupling high contaminant removal efficiencies with low operational costs. Anyway, further studies on process optimization with an emphasis on power requirements and electrode costs need to be carried out.
畜牧场废水含有高浓度的悬浮固体、有机污染物和氮化合物，如氨氮。未经适当处理就将畜牧场废水排放到水体中会导致严重的环境污染。与传统处理方法相比，电化学氧化具有更高的脱氮效率。在本研究中，通过实验室规模的反应器研究了从实际畜牧废水中电化学去除氨氮的方法。进行了初步实验，以研究包括硼掺杂金刚石和铱/钌涂层钛在内的不同阳极材料对使用合成废水的总氮去除效率的影响。硼掺杂金刚石是一种著名的非活性电极，其总氮降解效率可达63.7±1.21%。然而，属于活性阳极类别的铱/钌涂层钛电极表现出更高的性能，实现了78.8±0.76%的污染物降解。将铱/钌涂层钛阳极与不锈钢阴极耦合提高了系统性能，总氮去除率甚至达到了96.2±2.73%。采用优化的电池配置处理畜牧废水，添加氯化钠时，总氮降解率为67.0±2.25%，总有机碳降解率为37.3±0.68%。在处理过程结束时，铵含量被完全去除，初始氮中只有17.7±0.51%转化为硝酸盐。结果表明，所提出的系统是一种将高污染物去除效率与低运营成本相结合的处理畜牧废水的有前景的方法。无论如何，需要进一步开展关于工艺优化的研究，重点是电力需求和电极成本。
