生物炭三维电极对水中氨氮的去除机理

摘要

In order to investigate the removal mechanism of ammonia by biochar three⁃dimensional electrode, a lab⁃scale innovative three⁃dimensional electrode reactor using biochar as reactive media was established, and the removal trend and mechanism of ammonia (in non⁃chlorine water) during the reactor operation were investigated. Experimental results indicated that the biochar three⁃dimensional electrode reactor could achieve a high ammonia reduction in a short time (ρ0=100 mg/L, t=3 h,η=45.72%). The ammonia transform process is a hydroxyl consumption reaction, which fitted well with the first⁃order kinetic model well, and biochar adsorption contributed insignificantly on bulk ammonia removal, while the direct and indirect oxidation within the reactor would convert the ammonia nitrogen to gaseous nitrogen and nitrate nitrogen instead.%为考察生物炭三维电极对水中氨氮的作用机制，以生物炭为反应介质构建三维电极反应器，研究其对无氯水体中氨氮的去除效果，并探究水中氨氮的转化机理．结果表明，生物炭三维电极可以在短时间内对氨氮高效去除（氨氮初始质量浓度ρ0＝100 mg／L，t＝3 h，η＝45．72％），去除过程符合一级动力学模型，且氨氮的转化过程是一个消耗OH－的反应过程．反应器系统中反应产物分析证明，生物炭吸附作用对氨氮去除贡献甚微，氨氮主要通过直接氧化和间接氧化作用得以去除，最终转化为等量的N2和NO3－－N而得以去除．