含酚废水厌氧处理的影响因素及作用机制研究

发布时间：2018-05-30 04:36

本文选题：含酚废水 + UASB　；参考：《合肥工业大学》2017年硕士论文

【摘要】：本论文研究了萃取剂甲基异丁基(甲)酮(MIBK)、氨氮以及鸟粪石沉淀、高酚冲击等因素对含酚废水厌氧处理效能的影响,并通过分析污泥的比产甲烷活性、酚降解活性、粒度大小、污泥比阻等性质,揭示上述各因素对厌氧处理效能产生影响的作用机制,并得到如下的结果:(1)当进水总酚浓度为1000 mg·L~(-1)时,UASB出水总酚浓度约为0.22mg·L~(-1),且COD去除率大于97%。当进水中含有0.1 g·L~(-1) MIBK时,UASB反应器对酚类污染物的去除效能未受影响。但是,当进水MIBK浓度增至10 g·L~(-1)时,UASB反应器的总酚去除效率下降了1-2%。然而,厌氧污泥的比产甲烷活性却下降了45-75%。通过对MIBK厌氧降解性能的分析,发现其厌氧降解速率符合伪一级动力学方程(MIBK初始浓度为35 mg·L~(-1),k=0.0115 h~(-1),R~2=0.9664)。此外,在MIBK浓度分别为0.1,0.5,5和10 g·L~(-1)的条件下,MIBK的相对产甲烷速率常数分别为0.00816,0.00613,0.00273和0.00207 d-1。相较于苯酚降解速率,高浓度MIBK会短时抑制污泥的产甲烷活性。(2)当进水氨氮浓度为0.23,1,3 g·L~(-1)时,UASB反应器对总酚和COD的去除效率均维持在99.90%左右,厌氧污泥的活性未受到氨氮的显著影响。但是,当氨氮浓度提高至5 g·L~(-1)时,总酚和COD去除率分别下降了55%、12%。此时,污泥的产甲烷活性下降了72%。当氨氮浓度达到10 g·L~(-1),厌氧反应器的总酚去除率接近零,COD去除率仅为50%左右。采用鸟粪石沉淀法降低进水氨氮浓度,结合正交试验和反应器运行条件,确定当氨氮浓度为10 g·L~(-1)时,鸟粪石沉淀法去除氨氮的最优条件为:pH=8.5、n(Mg~(2+)):n(NH_4~+):n(PO_4~(3-))=1:1:1。在鸟粪石沉淀预处理与厌氧工艺组合运行条件下,总酚去除率恢复至60-80%。(3)当进水苯酚浓度达到1,2,4 g·L~(-1)时,UASB反应器对苯酚和COD的去除率分别维持在95%和90%以上。当进水苯酚浓度达到8 g·L~(-1)时,UASB反应器出水苯酚浓度快速上升至4.63 g·L~(-1),且污泥的比产甲烷活性受到严重抑制。
[Abstract]:In this paper, the effects of the extraction agents, such as methyl isobutyl (methyl) ketone MIBK, ammonia nitrogen, bird dung stone precipitation and high phenol impact on the anaerobic treatment efficiency of phenol containing wastewater were studied, and the specific methanogenic activity, phenol degradation activity and particle size of sludge were analyzed. The effects of the above factors on anaerobic treatment efficiency are revealed. The results are as follows: 1) when the influent total phenol concentration is 1000 mg / L ~ (-1), the total phenol concentration is about 0.22mg L ~ (1) ~ (-1), and the removal rate of COD is more than 97%. The removal efficiency of phenolic pollutants by UASB reactor was not affected when the influent contained 0.1 g L ~ (-1) MIBK. However, when the influent concentration of MIBK increased to 10 g / L ~ (-1), the removal efficiency of total phenol decreased by 1 ~ 2%. However, the specific methanogenic activity of anaerobic sludge decreased by 45-75. By analyzing the anaerobic degradation performance of MIBK, it is found that the rate of anaerobic degradation accords with the pseudo-first-order kinetic equation that the initial concentration of MIBK is 35 mg / L ~ (-1) ~ 0.0115 h ~ (-1) ~ 0.9664 ~ (-1). In addition, the relative methanogenic rate constants of MIBK were 0.00816 ~ 0.00613 ~ 0.00273 and 0.00207 d ~ (-1) under MIBK concentration of 0.1g / L ~ (-5) and 10 g / L ~ (-1), respectively. Compared with the degradation rate of phenol, high concentration of MIBK could inhibit the methanogenic activity of sludge for a short time. The removal efficiency of total phenol and COD was about 99.90% when the influent ammonia nitrogen concentration was 0.23 ~ 1g / L ~ (-1). The activity of anaerobic sludge was not significantly affected by ammonia nitrogen. However, when the concentration of ammonia nitrogen increased to 5 g / L ~ (-1), the removal rates of total phenol and COD decreased by 55 / 12 and 55 / 12, respectively. At this time, the methanogenic activity of sludge decreased by 72%. The removal rate of total phenol in anaerobic reactor is only about 50% when the concentration of ammonia nitrogen reaches 10 g / L ~ (-1). The method of bird dung stone precipitation was used to reduce the influent ammonia nitrogen concentration. In combination with the orthogonal test and the operating conditions of the reactor, it was determined that when the ammonia nitrogen concentration was 10 g / L ~ 1), the optimum conditions for removal of ammonia nitrogen by the bird dung stone precipitation method were as follows: (1) pH = 8.5% (n = 10). The optimum conditions for removal of ammonia nitrogen by the method were as follows: 1: 1: 1: 1: 1: 1: 1: 1: 1: 1: 1: 1. Under the combined operation conditions of gustonite precipitation pretreatment and anaerobic process, the removal rate of total phenol returned to 60-80%. 3) when the influent phenol concentration reached 1 ~ 2 ~ 2 ~ 4 g / L ~ (-1), the removal efficiency of phenol and COD in UASB reactor was over 95% and 90%, respectively. When the influent phenol concentration reached 8 g / L ~ (-1), the effluent phenol concentration of UASB reactor increased rapidly to 4.63 g / L ~ (-1), and the specific methanogenic activity of sludge was severely inhibited.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

【参考文献】