Department of Civil and Environmental Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Republic of Korea.
Department of Civil and Environmental Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Republic of Korea.
Water Res. 2018 Apr 1;132:200-210. doi: 10.1016/j.watres.2018.01.003. Epub 2018 Jan 5.
This research was based on the investigation of a major principle, regarding the effects of NaCl and KHPO concentrations on struvite recovery, with electricity production using magnesium-air fuel cell electrocoagulation, in accordance with the concentration of phosphorous and chloride. The weight ratio of N:P in the synthetic wastewater was in the range of 1.2-21. The concentration of NHCl was fixed at 0.277 M (approximately 3888 ppm as NH-N and 5000 ppm as NH), while PO-P was in the range of 0.006-0.1 M. In addition, the concentrations of NaCl as electrolyte were 0, 0.01, and 0.1 M. Phosphate removal increased linearly with the Mg:P ratio, up to approximately 1.1 mol mol, irrespective of the initial concentrations of phosphate and NaCl. The one-to-one reaction as mole ratio between phosphate and the dissolved Mg ions resulted in phosphate removal, with the production of a one-to-one magnesium/phosphate mineral, such as struvite. The average removal rate of phosphorous in experiments without a dose of NaCl was 4.19 mg P cm h, which was lower than the relative values of 5.35 and 4.77 mg P cm h, in experiments with 0.01 and 0.1 M NaCl. The dissolution rate of Mg with electro-oxidation determined the rate of phosphorous removal with struvite recovery. The average removal rates of phosphorous with dose concentrations of 0.006, 0.01 and 0.02 M KHPO were 4.02, 5.54, 6.9 mg P cm h, respectively, which increased with the increase in KHPO dose. However, in experiments with a dose of 0.05 and 0.1 M KHPO the average removal rates of phosphorous decreased to 4.84 and 2.51, respectively. The maximum power densities in the electrolyte mixture of 0.05 M KHPO/0.277 M NHCl, 0.01 M NaCl/0.05 M KHPO/0.277 M NHCl, and 0.1 NaCl/0.05 KHPO/0.277 M NHCl were 25.1, 26.4, and 33.2 W/m, respectively. The increase in the NaCl dose concentration resulted in an increase in the maximum power density and current density. A dose above 0.05 M KHPO resulted in the decrease of the maximum power densities. However, when the dose was below 0.05 M KHPO, the maximum power density increased with the increase in KHPO dose.
本研究基于对主要原理的调查，研究了 NaCl 和 KHPO 浓度对利用镁-空气燃料电池电凝聚回收鸟粪石的影响，以及电凝聚过程中磷和氯的浓度变化。合成废水中的 N:P 重量比在 1.2-21 之间。NHCl 的浓度固定在 0.277 M（约 3888 ppm 作为 NH-N 和 5000 ppm 作为 NH），而 PO-P 的浓度在 0.006-0.1 M 之间。此外，电解质 NaCl 的浓度分别为 0、0.01 和 0.1 M。磷酸盐去除率随 Mg:P 比呈线性增加，最高约为 1.1 mol mol，与磷酸盐和 NaCl 的初始浓度无关。磷酸盐与溶解的 Mg 离子按摩尔比反应生成磷酸盐去除，同时生成一种与 Mg 离子的摩尔比为 1:1 的磷酸盐矿物，如鸟粪石。没有添加 NaCl 剂量的实验中，磷的平均去除率为 4.19 mg P cm h，低于添加 0.01 和 0.1 M NaCl 剂量的实验中 5.35 和 4.77 mg P cm h 的相对值。Mg 通过电氧化溶解的速率决定了鸟粪石回收过程中磷的去除速率。KHPO 剂量浓度分别为 0.006、0.01 和 0.02 M 时，磷的平均去除率分别为 4.02、5.54、6.9 mg P cm h，随着 KHPO 剂量的增加而增加。然而，在 KHPO 剂量为 0.05 和 0.1 M 的实验中，磷的平均去除率分别降低至 4.84 和 2.51。在 0.05 M KHPO/0.277 M NHCl、0.01 M NaCl/0.05 M KHPO/0.277 M NHCl 和 0.1 NaCl/0.05 KHPO/0.277 M NHCl 的电解质混合物中，最大功率密度分别为 25.1、26.4 和 33.2 W/m。NaCl 剂量浓度的增加导致最大功率密度和电流密度的增加。KHPO 剂量高于 0.05 M 会导致最大功率密度降低。然而，当 KHPO 剂量低于 0.05 M 时，最大功率密度随 KHPO 剂量的增加而增加。
