College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China.
Aerospace Kaitian Environmental Technology Co., Ltd, Changsha, People's Republic of China.
Environ Technol. 2022 Aug;43(20):3161-3174. doi: 10.1080/09593330.2021.1916093. Epub 2021 May 2.
The effects of initial total phosphorus (TP) concentration, current density, conductivity and initial pH value on the removal rate of TP and energy consumption, as well as the behaviour and mechanism of phosphorus removal, were investigated by sinusoidal alternating current coagulation (SACC). The flocs produced by SACC were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy FTIR and X-ray photo electron spectroscopy. The thermodynamic and kinetic behaviours of phosphorus removal by iron sol adsorption were also studied in detail. In a self-made SACC reactor equipped with five sets of parallel iron electrodes spacing 10 mm, the removal rate of TP reached 90.9% for a pH 7.0 wastewater with 5 mg dm TP ( = 800 μS cm) after being treated for 60 min by applying 2.12 mA cm sinusoidal alternating current. Compared with direct current coagulation (DCC), SACC exhibits a higher removal efficiency of phosphorus due to the stronger adsorption of the produced flocs. It was found that the adsorption in the SACC process follows pseudo-second-order kinetic with the involvement of the intra-particle model. The adsorption of iron sol to phosphorus was an endothermic and spontaneous process, and its adsorption behaviour can be characterized with Langmuir and Redlich-Peterson isothermal adsorption models. SACC may be employed for the treatment of more complex wastewater combined with biological and/or electrochemical techniques.
正弦交流电凝聚（SACC）对初始总磷（TP）浓度、电流密度、电导率和初始 pH 值对 TP 去除率和能耗的影响，以及磷去除的行为和机制进行了研究。采用扫描电子显微镜、能谱仪、X 射线衍射、傅里叶变换红外光谱和 X 射线光电子能谱对 SACC 产生的絮体进行了表征。还详细研究了铁溶胶吸附去除磷的热力学和动力学行为。在一个自制的 SACC 反应器中，配备了五组平行铁电极，电极间距为 10mm，在 pH 为 7.0、初始 TP 为 5mg/dm（=800μS/cm）的废水中，经过 60min、施加 2.12mA/cm 的正弦交流电处理后，TP 的去除率达到 90.9%。与直流凝聚（DCC）相比，由于产生的絮体具有更强的吸附能力，SACC 表现出更高的磷去除效率。结果表明，SACC 过程中的吸附符合准二级动力学模型，并涉及到内颗粒模型。铁溶胶对磷的吸附是一个吸热和自发的过程，其吸附行为可以用 Langmuir 和 Redlich-Peterson 等温吸附模型来描述。SACC 可与生物和/或电化学技术相结合，用于处理更复杂的废水。
