State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; National Engineering Research Center of Dredging Technology and Equipment, Key Laboratory of Dredging Technology, CCCC, Shanghai 200082, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
School of Municipal and Ecological Engineering, Shanghai Urban Construction Vocational College, Shanghai 200432, China.
Water Res. 2024 Jul 1;258:121655. doi: 10.1016/j.watres.2024.121655. Epub 2024 Apr 26.
Ammonia recovery from wastewater is of great significance for aquatic ecology safety, human health and carbon emissions reduction. Electrochemical methods have gained increasing attention since the authigenic base and acid of electrochemical systems can be used as stripper and absorbent for transmembrane chemisorption of ammonia, respectively. However, the separation of electrodes and gas permeable membrane (GPM) significantly restricts the ammonia transfer-transformation process and the authigenic acid-base utilization. To break the restrictions, this study developed a gas permeable membrane electrode assembly (GPMEA), which innovatively integrated anode and cathode on each side of GPM through easy phase inversion of polyvinylidene fluoride binder, respectively. With the GPMEA assembled in a stacked transmembrane electro-chemisorption (sTMECS) system, in situ utilization of authigenic acid and base for transmembrane electro-chemisorption of ammonia was achieved to enhance the ammonia recovery from wastewater. At current density of 60 A/m, the transmembrane ammonia flux of the GPMEA was 693.0 ± 15.0 g N/(m·d), which was 86 % and 28 % higher than those of separate GPM and membrane cathode, respectively. The specific energy consumption of the GPMEA was 9.7∼16.1 kWh/kg N, which were about 50 % and 25 % lower than that of separate GPM and membrane cathode, respectively. Moreover, the application of GPMEA in the ammonia recovery from wastewater is easy to scale up in the sTMECS system. Accordingly, with the features of excellent performance, energy saving and easy scale-up, the GPMEA showed good prospects in electrochemical ammonia recovery from wastewater.
从废水中回收氨对于水生生态安全、人类健康和减少碳排放具有重要意义。由于电化学系统的自生基底和酸可分别作为汽提器和吸收剂用于氨的跨膜化学吸附，因此电化学方法受到了越来越多的关注。然而，电极和透气膜（GPM）的分离严重限制了氨的迁移转化过程和自生酸碱的利用。为了打破这一限制，本研究开发了一种透气膜电极组件（GPMEA），它通过聚偏二氟乙烯粘结剂的简单相转化，分别在 GPM 的每一侧创新性地集成了阳极和阴极。将组装好的 GPMEA 装入堆叠式跨膜电化学吸附（sTMECS）系统中，实现了自生酸和碱的原位利用，从而增强了从废水中回收氨。在 60 A/m 的电流密度下，GPMEA 的跨膜氨通量为 693.0±15.0 g N/（m·d），分别比单独的 GPM 和膜阴极高 86%和 28%。GPMEA 的比能耗为 9.7∼16.1 kWh/kg N，分别比单独的 GPM 和膜阴极低 50%和 25%。此外，GPMEA 在废水中氨回收中的应用在 sTMECS 系统中易于放大。因此，GPMEA 具有优异的性能、节能和易于放大的特点，在电化学氨回收方面具有广阔的前景。
