超临界水氧化法处理垃圾渗滤液的研究

Study of Supercritical Water Oxidation Process for Landfill Leachate Treatment

采用连续式超临界水氧化小试装置处理垃圾渗滤液,以双氧水作为氧化剂,研究了超临界水氧化反应的温度、压力、氧化剂比例K和催化剂等因素对渗滤液中污染物去除效果的影响,结果表明在不同温度、不同压力、不同K值单因素实验条件下,温度480℃,压力26 MPa,K=3.0是处理垃圾渗滤液的最佳工艺参数。试验加入催化剂能够提高COD和氨氮去除率,当Cu2+浓度为45 mg/L时,垃圾渗滤液中COD和氨氮去除率分别达到78.9%和38.8%。正交试验表明,主要的工艺参数中温度对处理效率的影响最大,其次是氧化剂比例K,压力影响最小。试验结果的氨氮去除率相对较低,这可能是由于垃圾渗滤液水质复杂,各污染物之间存在相互干扰,氨氮的去除机理还有待进一步的深入研究。

Landfill leachate was treated by supercritical water oxidation process in a laboratory bench-scale continuous-flow unit using hydrogen peroxide （H202） as an oxidant. Experiments were conducted to investigate the effects of the temperature, pressure, proportion of oxidant K and catalyst of the reactant on the removal of pollutants. Result showed that reaction temperature 480℃,reacfion pressure 26 MPa and K 3.0 was the best process parameters for leachate treatment.The removal rate of COD and ammonia nitrogen was improved when the catalyst was added, and when the concentration of Cu2＋ was 45 rag/L, the removal rate of COD and ammonia nitrogen of the landfill leachate was 78.9% and 38.8% respectively. The orthogonal experiment showed that, in the main process parameters, the influence of temperature on the treatment efficiency was the largest, followed by K, and the last was pressure. The removal rate of ammonia nitrogen was relatively low, which may be affected by many factors, and ammonia nitrogen removal remains to be further in-depth study.