臭氧微纳气泡高级氧化耦合工艺处理肼类废水

Treatment of hydrazine wastewater with ozone micro-nano bubbles advanced oxidation coupling process

以偏二甲肼(UDMH)推进剂废水为例探究臭氧微纳气泡对肼类废水的处理工艺,在混合效果方面,通过比较臭氧微纳气泡方式和传统曝气方式,表明前者的混合效果显著提升,其中气含率由0.18%提升到1.45%,臭氧传质系数提升2.1倍,说明微纳气泡明显提升臭氧传质效率。利用单纯臭氧微纳气泡和臭氧大气泡对偏二甲肼废水进行处理,结果表明臭氧微纳气泡技术处理后的偏二甲肼降解率、COD去除率和氨氮去除率分别比臭氧大气泡提升17.7%、14.6%和31.0%。但由于臭氧氧化的局限性,单纯依靠臭氧无法实现偏二甲肼废水的高效处理,通过探究紫外、H2O2和臭氧催化剂的强化工艺,发现臭氧微纳气泡与紫外和贵金属臭氧催化剂的耦合工艺效果最佳,COD去除率由20.2%提升到79.0%,并且在能耗对比中,该耦合技术优势明显。

Taking unsymmetrical dimethylhydrazine(UDMH)wastewater as an example,the ozone micro-nano bubbles treatment process was explored.Compared with traditional aeration mode,it was found that micro-nano bubbles could significantly improve the mixing efficiency,in which gas holdup increased from 0.18%to 1.45%.Moreover,ozone mass transfer coefficient increased by 2.1 times,suggesting that micro-nano bubbles improved the mass transfer of ozone.In the treatment experiment of UDMH,the degradation rate,COD and ammonia nitrogen removal by ozone micro-nano bubbles increase 17.7%,14.6%and 31.0%respectively in comparison with traditional aeration mode.However,ozone micro-nano bubbles can’t realize the efficient treatment of UNMH due to the limitation of ozonation.Exploring the enhanced method of UV,H2O2 and ozone catalysts to micro-nano bubbles,it was found that the combination of UV and precious metal catalysts could significantly enhance the treatment efficiency of ozone micro-nano bubbles,such as the COD removal reached 79.0%in comparison with 20.2%by traditional aeration mode.In addition,the energy consumption showed that the coupling process of micro-nano bubbles exhibited obvious advantages.