摘要
随着线路板的广泛应用,其在印刷过程中产生的铜氨废水的排放问题日益突出。铜氨废水中氨氮和铜离子对环境的危害较大,为了解决该问题,提出了一种MAP法和折点氯化法相结合的方法。该方法首先向铜氨废水中加入镁盐和磷酸盐,将氨氮转化为MAP沉淀,降低铜氨废水中氨氮的浓度,同时可以将MAP回收再利用;然后向剩余浓液中加入过量的NaClO溶液,进一步将溶液中的氨氮浓度降低,随着NaClO溶液的增加,反应液会逐渐呈碱性,而Cu^(2+)在碱性环境中会与OH-生成Cu(OH)_(2)沉淀,进而降低Cu^(2+)的浓度,从而使铜氨废水中的氨氮和Cu2+的浓度均符合《中华人民共和国环境保护法》的排放要求;最后通过纳氏试剂分光光度法和火焰原子吸收光度法检验反应后浓液中氨氮和Cu^(2+)的浓度。经过验证得知,该方法可以显著降低氨氮和Cu^(2+)的浓度。
With the widespread application of circuit boards,the problem of copper-ammonia wastewater discharge generated during the printing process has become increasingly prominent.This is because ammonia-nitrogen and copper ions in copper-ammonia wastewater cause significant harm to the environment.Therefore,to address these issues,this paper proposes a combined method of the MAP method and breakpoint chlorination.First,magnesium salts and phosphates are added to the copper-ammonia wastewater to convert ammonia-nitrogen into MAP precipitates,reducing the concentration of ammonia-nitrogen in the copper-ammonia wastewater.Meanwhile,the MAP can be recycled.Then,an excessive amount of NaClO solution is added to the remaining concentrated liquid to further reduce the ammonia-nitrogen concentration in the solution.As the amount of NaClO solution increases,the reaction solution gradually becomes alkaline.In an alkaline environment,Cu^(2+)reacts with OH-to form Cu(OH)_(2) precipitates,thereby reducing the concentration of Cu^(2+).As a result,the concentrations of both ammonia-nitrogen and Cu^(2+)in the copper-ammonia wastewater meet the discharge requirements of the"Environmental Protection Law of the People's Republic of China".Finally,the concentrations of ammonia-nitrogen and Cu^(2+)in the reaction-treated concentrated liquid are tested using Nessler's reagent spectrophotometry and flame atomic absorption spectrophotometry.Verification shows that the method proposed in this paper can significantly reduce the concentrations of ammonia-nitrogen and Cu^(2+).
作者
黄常亮
Huang Changliang(Guangzhou Kexiang Environmental Protection Co.,Ltd.,Guangzhou,Guangdong 510000)
出处
《现代工程科技》
2025年第1期77-80,共4页
Modern Engineering Technology
关键词
MAP法
铜氨废水
氨氮回收
线路板
折点氯化法
环保排放标准
MAP method
copper-ammonia wastewater
ammonia-nitrogen recovery
circuit board
breakpoint chlorination
environmental protection emission standards
