对硝基苯酚废水近临界水氧化工艺

The Technology of Near-Critical Water Oxidation of p-Nitrophenol Wastewater

采用超临界水氧化法新技术,通过正交试验研究了近临界水中对硝基苯酚废水处理的工艺条件。结果表明,温度、压力、停留时间、双氧水用量等各因素对对硝基苯酚及总有机碳(TOC)去除率有一定影响,各因素对TOC去除率的影响的显著性顺序为:反应温度>反应停留时间>双氧水用量>反应压力。实验得出了反应的最佳工艺条件为:温度320℃,压力14 MPa,停留时间72 s,双氧水用量为计量倍数的4倍,反应后对硝基苯酚的去除率接近100%,TOC含量18.8 mg/L,优于国家污水排放一级标准。

Supercritical water oxidation is a new technology of treating all kinds of organic, in this paper, the orthogonal test was designed to research the technological conditions of the oxidation experiments which were carried in near-critical water. The experiment results showed that the reaction temperature, pressure, residence time and the dosage of oxidant all had important influence on the p-nitrophenol and TOC removal efficiency, the reaction temperature was the most important factor affected the TOC removal efficiency, then the residence time, the dosage of oxidant and the least important factor was the pressure Through analyzing the results of experiment, the optimal reaction condition was as follows：T=320℃,p=14 MPa, F72 s, and degree of excess oxygen 4. At this experiment conditions, TOC value was 18.8 mg/L, which had met the wastewater discharge demand of national standard.