共查询到16条相似文献,搜索用时 109 毫秒
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短程硝化--反硝化生物脱氮工艺的研究进展 总被引:2,自引:0,他引:2
短程硝化反硝化生物脱氮工艺是将硝化控制在形成亚硝酸阶段,阻止亚硝酸的进一步硝化,然后直接进行反硝化。本文结合国内外的研究,对短程硝化脱氮技术的实现途径进行了概括和探讨,对该工艺的开发应用(如SHARON工艺、OLAND工艺、CANONT艺和生物膜/活性污泥法结合的短程硝化反硝化工艺)作了简要综述,并指出了该工艺的技术优势和应用价值。 相似文献
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一、生活污水处理方法 1. AAA污水处理方法 这是一种间断性曝气的生物处理过程,通过好氧过程和厌氧过程的交变来消解水中污染物。 AAA是一种带澄清槽和污泥循环的活性污泥系统,连续进、出水,通过传感器检测污水中溶解氧浓度的变化速率来动态地控制曝气量和曝气时间,从而发生硝化和反硝化生物脱氮反应。特点是:曝气能量最小,可连续地控制使 BOD和氮得到最优化地去除,出水中悬浮污泥少,有溶解氧传感器的失灵报警。用 AAA对现有工艺进行改进,可降低成本。 2. APT预发酵生物除磷和氮 APT是 Activated Primar… 相似文献
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ABSTRACT: When a series of aerators are used to raise the level of dissolved oxygen in a polluted stream through instream artificial aeration augmentation, the system is governed by the basic dissolved oxygen mass balance equation with the existence of artificial aeration as its boundary conditions. A mathematical model is formulated for the optimization of the allocation of aeration capacity to each of the series of aerators subject to a limitation on total available aeration capacity. The objective function is the minimization of the sum of the squares of the aeration costs and the costs incurred by damaging or unnecessarily improving the system. The original constrained allocation problem is simplified by converting it to an unconstrained one via the use of Lagrange multiplier. A discretized dynamic programming algorithm is formulated for finding the optimal allocation policy. A typical optimal aeration capacity allocation policy and its corresponding dissolved oxygen sag profile for the illustrated numerical example is presented, and the relationship between the total available aeration capacity and Lagrange multiplier is also developed treating weighting factors as parameters. 相似文献
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城镇污水处理厂低浓度连续进水间歇曝气运行模式分析 总被引:3,自引:0,他引:3
根据南方城镇污水处理厂建成运行初期的实际运行情况,对低浓度进水的运行模式进行了分析和研究。运行中,污水处理厂MISS浓度调整为25g/L,采用曝气3h、停曝5h、连续进水的运行模式,实现了生物系统稳定运行,出水达标。 相似文献
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Barry C. Moore Ping-Hung Chen William H. Funk David Yonge 《Journal of the American Water Resources Association》1996,32(4):723-731
ABSTRACT: Hypolimnetic aeration is a widely used technique for lake restoration and fisheries enhancement. However, system design still depends on application of “safety factors” to observed oxygen demand rates, in large part because actual oxygen demand may be greater after aeration than before. Laboratory incubations of sediment show that sediment oxygen demand (SOD) rates follow mixed order kinetics, with an initial period of zero order reaction, followed by first order kinetics. The transition from zero to first order kinetics may correspond to the transition from laminar to turbulent flow. This suggests that SOD reaction kinetics are governed by thickness of the diffusive sublayer adjacent to the sediments. Therefore, zero and first order reaction regions correspond with oxygen diffusion limitation and substrate limitation, respectively. Such a mechanism would account for the induced oxygen demand observed following hypolimnetic aeration and would reconcile differences in SOD reaction orders noted in the literature. This paper describes development of equations based on laboratory SOD incubations for predicting induced oxygen demand following hypolimnetic aeration. 相似文献
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The PEMMC-Biobarrel (packed-bed of entrapped mixed microbial cells with Bio-barrel) process and MEMMC-Biobarrel (moving EMMC-Biobarrel) process were investigated for enhancing concurrent organic and nitrogen removal with applied intermittent aeration. For the PEMMC-Biobarrel process, the EMMC-Biobarrel carriers were employed at a packing ratio of 20%. In the MEMMC-Biobarrel process, the EMMC-Biobarrel carriers with a packing ratio of 10% were added along with the activated sludge (AS) in the bioreactor. Three different hydraulic retention times (HRTs) of 9, 6 and 4 h were applied. Aeration was provided intermittently at time schedules of 1 h air on/1 h air off, 1 h on/1.5 h off and 1 h on/2 h off. Nitrogen removal in the PEMMC-Biobarrel system was not improved by increasing the intermittent non-aeration time period. On the other hand, the MEMMC-Biobarrel process enhanced nitrogen removal with increasing non-aeration time even though the SCOD/N(TIN) ratio decreased from 6 to 4. Significant denitrification during the aeration cycle was observed in the MEMMC-Biobarrel process. The MEMMC-Biobarrel process demonstrated the most efficient organic and nitrogen removal at an HRT of 6 h with an intermittent aeration time schedule of 1 h on/2 h off. Nitrogen removal of 80% was achieved, which was about 15% higher compared to the AS system. TCOD and SCOD removal efficiencies were 80% and 75%, respectively. 相似文献
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Christopher R. Ellis Heinz G. Stefan 《Journal of the American Water Resources Association》1991,27(6):903-914
ABSTRACT: Artificial aeration is used to prevent winter fish kills due to oxygen depletion in ice-covered lakes. Conventional aeration by air bubble plumes and other techniques usually mixes the water column and produces hazardous open water in the ice cover. A non-mixing winter lake aeration system which creates a fish refuge was designed and field tested to oxygenate the water and maintain water temperature stratification in a lake such that no open water is created. The system uses a cascade aerator and has a design discharge and dissolved oxygen input rate of 85 1/s and 70 kg/d, respectively. Aerated water is discharged near mid-depth with minimum disturbance of the ambient water through a specially designed diffuser. The system was tested in a shallow 3 m deep lake of 17 ha surface area during two winters and was found to perform as expected. Significant photosynthetic production of dissolved oxygen under the ice-cover was also observed during snow-free periods. 相似文献