面向污泥减量化的侧流水解强化脱氮技术研究

发布时间：2018-11-27 09:36

【摘要】：目前,随着中国经济的急速发展,城市市政污水和各种工业废水的处理量逐渐提高,带来的一个结果是污泥总量的快速增长。而污泥的最终处理处置不但需要较高的费用,且容易带来二次污染问题。因而,如何对剩余污泥进行经济有效地最终处置,从源头上减少污泥产量,同时又不影响污水处理的效果,甚至提高出水效果,是未来一段时间内环保界人士所关注的难题之一。本文针对常见的低C/N污水处理过程中需要外加大量的碳源以保持一定的脱氮除磷效率问题,提出利用剩余污泥溶胞破壁后释放的内碳源作为外加碳源回流进入主体脱氮工艺中,研究系统在外加内碳源后脱氮除磷效率的变化和剩余污泥的减量化、资源化效果。首先对剩余污泥进行超声波预处理,在超声波的作用下,剩余污泥细胞壁破解,内容物释放出来进入系统。使系统中的SCOD、氨氮、总氮均有较大程度的增加。最佳超声波工艺参数为0.4W/m L的声能密度作用20min,此时系统上清液中SCOD浓度为517 mg/L,氨氮浓度为17.24 mg/L,总氮浓度为52.94 mg/L,释放了较多的碳源,利于后续实验利用。显微镜下观察污泥细胞被完全破解,提高了溶胞率,有利于污泥减量。其次,在利用A/O装置进行脱氮污泥的快速驯化过程中,控制条件初始进水氨氮=20mg/L,COD=200mg/L,总磷=5mg/L,C/N=10,随着实验的进行逐步提高进水C、N浓度,同时C/N递减到6.67。最终进水指标氨氮=180 mg/L,COD=1200 mg/L,总磷=17mg/L,出水氨氮1mg/L,COD50mg/L,总磷1mg/L,总氮去除率达86%左右。驯化好的脱氮污泥通过实际油墨废水进行验证实验,结果表明在进水稀释一倍的情况下,油墨废水的COD、氨氮去除率达95%以上,总氮去除率达83%,说明脱氮污泥驯化成功。最后通过全过程对照实验研究污泥内碳源回流对系统的影响,结果实验组与对照组的出水氨氮、COD、总磷浓度没有明显差别,均在小范围内波动。实验组出水平均总氮浓度虽然从24.50mg/L增加到27.38mg/L,但总氮的去除率也从86.39%增加到88.17%。在污泥减量化方面,通过计算两套系统的累积剩余污泥排放量和表观产率,对照组在试验阶段累积排放1019.8g污泥,污泥产率0.242g-MLSS/g-COD;实验组累积排放剩余污泥783.2g,污泥产率为0.131g-MLSS/g-COD,实现了23.20%的污泥减量率。
[Abstract]:At present, with the rapid development of Chinese economy, the treatment capacity of municipal sewage and various industrial wastewater is increasing gradually, which results in the rapid growth of the total amount of sludge. The final disposal of sludge not only requires high cost, but also brings secondary pollution easily. Therefore, how to dispose surplus sludge economically and effectively, reduce sludge output at source without affecting the effect of sewage treatment, and even improve the effluent effect, It is one of the problems that the environmental protection sector will pay close attention to for some time to come. In this paper, the common low C / N wastewater treatment process requires a large number of carbon sources to maintain a certain nitrogen and phosphorus removal efficiency. In this paper, the internal carbon source released after the dissolution of excess sludge into the main nitrogen removal process was put forward. The change of nitrogen and phosphorus removal efficiency, the reduction of excess sludge and the utilization effect of the system were studied. First, the excess sludge was pretreated by ultrasonic wave, the cell wall of the excess sludge was cracked, and the contents were released into the system. The SCOD, ammonia nitrogen and total nitrogen in the system were increased to a large extent. The optimum ultrasonic parameters were the sound energy density of 0.4W/m L for 20 minutes, and the SCOD concentration in the supernatant was 517 mg/L, ammonia nitrogen concentration was 17.24 mg/L, total nitrogen concentration was 52.94 mg/L, and more carbon sources were released. It is propitious to follow up the experiment. The observation of sludge cell was completely cracked under microscope, which increased the cell dissolution rate and was beneficial to sludge reduction. Secondly, during the rapid domestication process of denitrification sludge using the A / O plant, the initial influent ammonia nitrogen = 20 mg / L CODN = 200mg / L, total phosphorus = 5 mg / L C / N = 10, as the experiment was carried out, the influent concentration of Con N was gradually increased. At the same time, C / N decreased to 6.67. The final influent index ammonia nitrogen = 180 mg/L,COD=1200 mg/L, total phosphorus = 17 mg / L, effluent ammonia nitrogen 1 mg / L COD 50 mg / L, total phosphorus 1 mg / L, total nitrogen removal rate is about 86%. The results showed that the removal rate of COD, ammonia nitrogen and total nitrogen removal rate of ink wastewater were more than 95% and 83% respectively, which indicated that the denitrification sludge was domesticated successfully. Finally, the effect of carbon source reflux on the system was studied through the whole process control experiment. The results showed that the effluent ammonia nitrogen and total phosphorus concentration of COD, in the experimental group and the control group had no significant difference, and all fluctuated in a small range. The average total nitrogen concentration in the effluent of the experimental group increased from 24.50mg/L to 27.38 mg / L, but the removal rate of total nitrogen increased from 86.39% to 88.17%. In the aspect of sludge reduction, the cumulative excess sludge discharge and apparent yield of the two systems were calculated. In the control group, 1019.8g sludge was discharged, and the sludge yield was 0.242g-MLSS / g-COD. The sludge yield of the experimental group was 0.131g-MLSS / g-COD, and the sludge reduction rate of 23.20% was achieved.
【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

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