基于硫酸根自由基的高级氧化技术深度处理造纸废水的研究

Advanced Treatment of Papermaking Wastewater by Sulfate Radical-based Advanced Oxidation Process

采用零价铁(ZVI)活化过硫酸钠(PS)产生硫酸根自由基的高级氧化技术处理造纸废水二级出水(CODCr为160 mg/L,色度为200度),考察了常温下pH值、ZVI用量、PS用量等因素对CODCr降解率及色度去除率的影响,并对其降解过程动力学进行了探讨,初步确定了硫酸根自由基氧化降解造纸废水的工艺条件,通过采用GC-MS检测分析了废水处理前后的物质变化情况。结果表明,在酸性至中性条件下,硫酸根自由基皆可有效降解有机污染物;在ZVI用量为8 g/L、PS用量为4 g/L时,室温条件下反应3h后,初始pH值为3和未调节pH值废水的CODCr降解率分别达到57.5%和34.2%,色度去除率分别达到83%和89%;通过GC-MS检测分析可知二级出水中含35种有机污染物,经过硫酸根自由基氧化降解后废水中苯类物质得到了一定的降解,相对含量有一定的变化,但种类基本没变。

Typically, pulping and paper making wastewater contains high levels of non-biodegradable organics, and this type of organics still exist after secondary treatment. This paper reports the first scientific study to apply sulfate radical （SO4^- ）-based advanced oxidation process （SR-AOP） to treat papermaking wastewater, with an emphasis of removal of COD and color of refractory organics. Using zero-valent iron （ZVI） activated persulfate （PS） for the oxidation of the wastewater after secondary treatment（ CODer of 160 mg/L, color of 200 degrees） was studied through a series of batch experiments. The effect of pH on the degradation efficiency of wastewater was investigated on the condition of room temperature, also the effects of ZVI dosage and PS dosage were examined. The results showed that, the efficiencies of CODcr degradation or color removal are about 57.5% and 83% at condition of pH = 3 within 5h, or about 34.2% and 89% at condition of pH = 8.14 with 3h when the ZVI dosage was 8 g/L and PS dosage was 4 g/L respectively. The secondary treatment wastewater and the advanced treatment wastewater with SR-AOP were qualitative analyzed and quantitative determined using GC-MS analyzer, the results showed that some of organics were removed and others were partially degraded after advanced treatment.