| 流量分配对分段进水A/O工艺脱氮性能的影响 |
| 摘要点击 2714 全文点击 2215 投稿时间：2008-01-23 修订日期：2008-04-04 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 生活污水 脱氮 分段进水 A/O 流量分配 |
| 英文关键词 domestic wastewater nitrogen removal step-feed A/O influent flow distribution |
|
| 中文摘要 |
| 采用分段进水A/O中试脱氮系统处理实际生活污水,为充分利用原水碳源,采用流量分配系数法对进水流量进行分配.在高、低负荷,进水COD/TKN分别为3、 5、 7、 9、 11、 13下,研究流量分配比对分段进水A/O工艺脱氮性能的影响.结果表明,在高负荷、低C/N(COD/TKN＜5)下,按流量分配系数分配流量,会造成系统硝化容量浪费,导致氨氮去除效果下降.而在高负荷、高C/N(COD/TKN＞9),由于首端氨氮负荷过高,氨氮不能完全氧化,导致后段反硝化电子受体不
足,造成系统碳源浪费,结果随C/N提高,总氮(TN)去除率却逐渐降低.而低负荷下,由于不存在硝化限制,系统TN去除率随进水C/N升高而升高,当C/N为13时,出水TN<2 mg/Ｌ,最高TN去除率可达976%.高、低负荷,不同C/N下的试验结果证明,高C/N污水(C/N＞α),采用流量分配系数分配流量,可充分利用原水碳源,提高TN去除效率,但需保证各段硝化完全.而低C/N污水(C/N＜α),C/N是决定TN去除率的关键因素,从保证硝化效果、利于硝化菌生长的角度考虑,不宜采用流量分配系数法分配流量,各段等负荷分配流量是一个可能的选择. |
| 英文摘要 |
| In order to optimize the utilization of influent carbon source, a feeding pattern so-called “coefficient of influent flow rate" was adopted in a pilot-scale step-feed A/O process treating domestic wastewater. The effects of influent flow distribution ratio on nitrogen removal efficiency were investigated when the reactor was operated at different loading rates and COD/TKN ratio of 3, 5,
7, 9, 11, 13, respectively. The experiment results indicated that the wasting of ni trification capacity occurred when high loading rate and low C/N ratio (COD/TKN＜5) were applied, while ammonia removal efficiency was decreased obviously at the same time. When the system was operated at high loading rate and high C/N ratios, the insufficient nitrification occurred in first stage, which resulted in the absence of electron accepter in the downstream anoxic zone. Consequently, the to
tal nitrogen (TN) removal efficiency was decreased even though the COD/TKN was higher than 9. However, due to the unlimited nitrification, the increased C/N ratio led to an enhancement of TN removal efficiency when the system was operated at low influent loading rate. When the influent COD/TKN was kept at 13 around, relatively low effluent TN concentration less than 2 mg/Ｌ, and a highest TN removal efficiency of 976% were achieved, respectively. For the feeding pattern sele
cted for the study, the conclusions obtained from the experiment results showed that the influent flow coefficient method could use carbon source sufficiently and decrease the influent flow rate of last stage when the wastewater with higher C/N(C/N＞α) was fed. However, a completely nitrification should be promised in each stage during this period. When the wastewater with low C/N ratio (C/N＜α), due to the limited carbon source, C/N is the key parameter for TN removal efficiency. From the point view to favor the growth of nitrifiers and satisfy the ammonia effluent standard, the balanced loading of nitrifiers in each stage strategy maybe substitute the feeding pattern proposed in this study as an optimal choice. |
|
|
|
