间歇曝气SBR与传统SBR处理养猪沼液的比较研究

采用间歇曝气序批式反应器(intermittently aerated sequencing batch reactor,IASBR)和传统序批式反应器(SBR)处理养猪沼液,研究进水中化学需氧量(COD)与总氮(TN)比值(COD/TN)和运行负荷对污染物去除效果的影响.结果表明,在进水COD/TN约为2.2、氨氮负荷为(0.12±0.04)kg·(m3·d)-1时,IASBR中的氨氮、TN和有机物去除率分别为97.2%±4.4%、81.5%±7.5%、88.5%±2.4%,优于SBR的78.3%±19.6%、79.8%±4.9%、86.6%±3.2%;当氨氮负荷提高至(0.18±0.02)kg·(m3·d)-1时,IASBR中的氨氮、TN和有机物去除率略有降低,分别为92.4%±7.3%、77.5%±5.3%、86.4%±2.2%,但仍然优于SBR中的相应去除率78.1%±15.4%、61.8%±11.2%、81.8%±5.6%.在氨氮负荷为(0.20±0.01)kg·(m3·d)-1下,提高进水COD/TN至约3.0,则IASBR和SBR的污染物去除能力较进水COD/TN为2.2时有显著提升,IASBR中氨氮、TN和有机物去除率分别达到99.6%±0.2%、91.5%±2.9%和92.0%±0.9%,仍然高于SBR的90.2%±1.4%、83.0%±1.9%、90.2%±0.5%.总体而言,相较SBR,IASBR对TN和氨氮的去除更高效、耐冲击负荷能力更强,因此对养猪沼液等低碳氮比的废水更为适用.

A Comparative Study on Performance of an Intermittent Aeration SBR and a Traditional SBR for Treatment of Digested Piggery Wastewater

An intermittently aerated sequencing batch reactor (IASBR) and a traditional sequencing batch reactor (SBR) were respectively used for treating digested piggery wastewater, and the pollutant removal performance was studied at different ratios of chemical oxygen demand (COD) to total nitrogen (TN) in the influent and different loading rates. The results showed that the pollutant removal rates in the IASBR were much higher than those in the SBR. Under influent COD/TN of about 2.2 and NH₄⁺-N loading of (0.12±0.04) kg·(m³·d)^-1, the removal rates of NH₄⁺-N, TN and TOC in the IASBR were 97.2%±4.4%, 81.5%±7.5% and 88.5%±2.4%, respectively, higher than the corresponding rates of 78.3%±19.6%, 79.8%±4.9% and 86.6%±3.2% in the SBR. As the NH₄⁺-N loading was increased to (0.18±0.02) kg·(m³·d)^-1, the removal rates of NH₄⁺-N, TN and TOC in the IASBR were slightly decreased to 92.4%±7.3%, 77.5%±5.3% and 86.4%±2.2%, but still higher than the corresponding values of 78.1%±15.4%, 61.8%±11.2% and 81.8%±5.6% in the SBR. As the NH₄⁺-N loading was remained at (0.20±0.01) kg·(m³·d)^-1, but the influent COD/TN ratio was increased to about 3.0, the pollutant removal rates in both IASBR and SBR were increased, compared to those at influent COD/TN ratio of 2.2.The removal rates of NH₄⁺-N, TN and TOC in the IASBR were 99.6%±0.2%, 91.5%±2.9% and 92.0%±0.9%, respectively, higher than the corresponding rates of 90.2%±1.4%, 83.0%±1.9% and 90.2%±0.5% in the SBR. Based on the above, the IASBR was more efficient in TN and ammonium removal and more shocking load resistant, and therefore was more feasible than SBR for treating low COD/TN ratio wastewaters such as the digested piggery wastewater.