电凝聚法处理家具工业废水。

Electrocoagulation treatment of furniture industry wastewater.

机构信息

Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal.

Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal; CIEPQPF-Chemical Engineering Processes and Forest Products Research Centre, Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Rua Sílvio Lima, 3030-790, Coimbra, Portugal.

出版信息

Chemosphere. 2023 Jul;328:138500. doi: 10.1016/j.chemosphere.2023.138500. Epub 2023 Mar 22.

DOI:10.1016/j.chemosphere.2023.138500

PMID:36963577

Abstract

Electrocoagulation was investigated as a method for treating wastewater containing polyvinyl acetate (PVAc) from the furniture industry. The study evaluated the evolution of iron concentration and passivation during the treatment process. Laboratory-scale experiments were conducted to evaluate the effects of inter-electrode distance (d), current density, and mode on treatment performance. Three values of d (0.3, 0.6, and 0.9 cm) were studied and found to have no significant effect on performance. However, lower d values resulted in reduced energy consumption due to a decrease in applied voltage. Three values of current density (132, 158, and 197 A m) were studied under two current modes, Direct Current (DC) and Alternating Pulsed Current (APC). The best treatment performance for DC occurred under 158 A m (the treated wastewater was characterized by pH = 4.59 ± 0.02, conductivity = 996 ± 21 μS cm, COD = 1940 ± 55 mgO L, TSS = 105 ± 14 mg L, and Fe = 50.39 ± 1.87 mgFe L). For APC, the best performance was achieved under 197 A m (the treated wastewater was characterized by pH = 6.33 ± 0.06, conductivity = 988 ± 17 μS cm, COD = 1942 ± 312 mgO L, TSS = 199 ± 55 mg L, and Fe = 44.68 ± 4.60 mgFe L). Despite the promising results, treatment performance was insufficient to meet the legal requirements for water discharge. APC was found to be a more economically viable approach, as it reduced anode wear, electrode passivation, and energy consumption. The quantity of iron released increased with d, and the effect of current density on iron concentration was found to be non-linear. However, applying APC reduced the iron content for all tested current densities. The tests showed that EC was effective in removing chemical oxygen demand (COD) and total suspended solids (TSS), achieving removal efficiencies above 92% and 99%, respectively. However, the studied treatment procedures were insufficient to meet the EU legal requirements for water discharge. Therefore, the obtained wastewater should undergo a post-treatment process.

摘要

电化学混凝法被研究用于处理来自家具行业的含聚醋酸乙烯（PVAc）的废水。本研究评估了在处理过程中铁浓度和钝化的演变。进行了实验室规模的实验来评估电极间距离（d）、电流密度和模式对处理性能的影响。研究了 3 个 d 值（0.3、0.6 和 0.9 cm），发现它们对性能没有显著影响。然而，较低的 d 值由于施加电压的降低而导致能耗降低。在两种电流模式（直流（DC）和交流脉冲电流（APC））下研究了 3 个电流密度（132、158 和 197 A m）。对于 DC，电流密度为 158 A m 时处理效果最佳（处理后的废水的 pH 值为 4.59 ± 0.02，电导率为 996 ± 21 μS cm，COD 为 1940 ± 55 mgO L，TSS 为 105 ± 14 mg L，Fe 为 50.39 ± 1.87 mgFe L）。对于 APC，电流密度为 197 A m 时处理效果最佳（处理后的废水的 pH 值为 6.33 ± 0.06，电导率为 988 ± 17 μS cm，COD 为 1942 ± 312 mgO L，TSS 为 199 ± 55 mg L，Fe 为 44.68 ± 4.60 mgFe L）。尽管结果很有前景，但处理性能仍不足以满足废水排放的法律要求。APC 被发现是一种更具经济可行性的方法，因为它减少了阳极磨损、电极钝化和能耗。随着 d 的增加，释放的铁量增加，而电流密度对铁浓度的影响是非线性的。然而，施加 APC 降低了所有测试电流密度下的铁含量。测试表明，EC 有效去除化学需氧量（COD）和总悬浮固体（TSS），去除效率分别超过 92%和 99%。然而，所研究的处理程序不足以满足欧盟对废水排放的法律要求。因此，获得的废水应进行后处理。