高负荷活性污泥法处理城市污水系统污泥产量的确定

根据高负荷活性污泥法处理系统对溶解性和颗粒性污染物的去除程度和机理不同,通过大量试验数据的回归拟合,提出了高负荷活性污泥法处理系统处理城市污水污泥产量的经验公式,并得到污泥表观产率Y0值,为今后高负荷活性污泥系统的工业化处理装置的设计、运行及理论研究提供一定的参考依据。     

基于FNA处理污泥实现城市污水部分短程硝化

为实现城市污水短程硝化厌氧氨氧化生物脱氮,以去除有机物的实际污水为研究对象,考察了游离亚硝酸盐(FNA)处理污泥实现城市污水部分短程硝化的可行性。 结果表明,FNA处理活性污泥后,亚硝酸盐氧化菌(NOB)的亚硝酸盐氧化速率下降程度大于氨氧化菌(AOB)的氨氧化速率,且在0～0.75 mg HNO₂-N·L^-1范围内随着FNA浓度的增加抑制作用增强。接种实际污水厂活性污泥后,系统亚硝酸盐(NO₂^--N)积累率仅为1%,即为全程硝化。在控制污泥龄约为15 d的条件下,采用FNA处理污泥可使系统亚硝酸盐积累率增加至90%以上。水力停留时间调至2.5 h时,实现了部分短程硝化,且出水NO₂^--N/NH₄⁺-N平均值为1.24,可满足厌氧氨氧化脱氮反应的要求。因此采用FNA处理污泥,结合水力停留时间和污泥龄控制可实现城市污水部分短程硝化。     

Supervisory control system to enhance partial nitrification in an activated sludge reactor

This work proposes a supervisory control system based on an optimization layer to calculate the optimum pH and dissolved oxygen (DO) set-points for the SISO controller, maintaining the process at stable partial nitrification. Takagi–Sugeno fuzzy multimodels were implemented to estimate ammonium degradation and nitrite accumulation from on-line DO and pH values, and updated using off-line measurements. An activated sludge reactor was operated successfully over 115 consecutive days with the supervisory control system, achieving ammonium degradation and nitrite accumulation values higher than 95% and 80%, respectively. The on-line estimates of the multimodels showed a prediction error of less than 7% at steady state operation, and reflected the tendencies shown in experiment to be caused by changes in pH value and DO concentration.     

Nitrate control strategies in an activated sludge wastewater treatment process

We studied nitrate control strategies in an activated sludge wastewater treatment process (WWTP) based on the activated sludge model. Two control strategies, back propagation for proportional-integral-derivative (BP-PID) and adaptive-network based fuzzy inference systems (ANFIS), are applied in the WWTP. The simulation results show that the simple local constant setpoint control has poor control effects on the nitrate concentration control. However, the ANFIS (4*1) controller, which considers not only the local constant setpoint control of the nitrate concentration, but also three important indices in the effluent—ammonia concentration, total suspended sludge concentration and total nitrogen concentration—demonstrates good control performance. The results also prove that ANFIS (4*1) controller has better control performance than that of the controllers PI, BP-PID and ANFIS (2*1), and that the ANFIS (4*1) controller is effective in improving the effluent quality and maintaining the stability of the effluent quality.     

多级活性污泥法处理糠醛生产废水

采用多级活性污泥法工艺处理糠醛生产废水,该工艺运行稳定。运行结果表明,在进水CODCr的质量浓度为12 000～14 000 mg/L,BOD5的质量浓度为5 600 mg/L,pH值在3～4的条件下,处理出水CODCr的质量浓度达到56 mg/L,BOD5的质量浓度达到15 mg/L,去除率均超过99%,出水水质达到GB 8978—1996《污水综合排放标准》的一级排放标准。     

生物滤池-活性污泥法处理啤酒废水的实践

衡阳啤酒厂废水处理站设计规模为2100m^3/d;进水CODCr=800-1500mg/L,BOD5=400-800mg/L,SS=300-600mg/L。采用高负荷生物滤池－活性污泥法处理工艺,运行表明出水水质达到GB8978－1988污水综合排放标准中规定的一级标准,且投资省。     

污水处理活性污泥法流态分析

阐述了活性污泥法的两种流态,分析比较了推流式和完全混合式曝气池的池型、曝气方式、水力特征、各自的特点和存在问题、反应内在规律、去除率、适用水质等,从理论上证明了同样的污水水质若达到同样的处理效果,则推流式曝气池的动力学负荷、体积处理负荷均大于完全混合式;推流式曝气池需氧量小于完全混合式;推流式曝气池比完全混合式曝气池经济。     

活性污泥法处理洗浴废水的中水工艺试验研究

洗浴废水属优质杂排水,是中水处理的主要水源.本试验采用SBR法,利用生活污水直接曝气产生活性污泥,并对其培养驯化,使其适应处理洗浴废水.试验证明经洗浴废水渐变比例驯化培养,活性污泥微生物可很好地适应洗浴废水的水质,微生物活性较高、表现活跃,洗浴废水对活性污泥微生物的影响较小,其出水CODCr去除率可达到74.1%,经过处理后的洗浴废水达到中水回用标准;推出洗浴废水SBR活性污泥法中水处理工艺的最佳负荷为0.07～0.10 kg/(kg·d),该负荷可作为SBR法处理洗浴废水运行操作的参考依据.     

Role of intermittent aeration in domestic wastewater treatment by submerged membrane activated sludge system

In this study, the treatment of domestic wastewater in a lab-scale submerged membrane activated sludge system (sMBR) was investigated under different aeration intervals. The COD concentration of the system effluent varied generally between 5 and 25 mg/l and the COD removal at the organic loads of 0.6-0.8 kg COD/m³.d was observed to be above 98%. The total phosphorus content of the filtrate was decreased to a level that was less than 1 mg/l under the aerobic conditions in which the aeration was continuously made. A dramatic increase in the total phosphorus content of filtrate was observed under the aerobic + anoxic conditions in which the aeration was made at differential intervals. The filtrate was free of suspended solid (SS) and total coliform bacteria and a percent removal of 100 was achieved in terms of these parameters. The influent turbidity removal was 97-99.8%. Generally, the removal of total Kjeldahl nitrogen (TKN) and ammonium nitrogen varied in the ranges of 87.8-99.1% and in the ranges of 89.4-99.8%, respectively. While the nitrate concentrations in the filtrate increased to 26.8 mg/l under the aerobic conditions, it was determined that this value was decreased to 2.4 mg/l under the aerobic + anoxic conditions.     

活性污泥法污水处理厂的运行模拟

结合ASM1和二沉池模型组成活性污泥模拟系统,将某污水处理厂的常规检测数据转化为活性污泥系统模型所需的组分数据,然后调整模型参数,使污水处理厂出水指标最接近于污水处理厂实际数据,从而确定适合该污水处理厂的模型参数,最后对该污水处理厂的工艺参数进行了模拟改造。     

Design of a modern automatic control system for the activated sludge process in wastewater treatment

The Activated Sludge Process (ASP) exhibits highly nonlinear properties. The design of an automatic control system that is robust against disturbance of inlet wastewater flow rate and has short process settling times is a chal enging matter. The proposed control method is an I-P modified controller automatic control system with state variable feedback and control canonical form simulation diagram for the process. A more stable response is achieved with this type of modern control. Settling times of 0.48 days are achieved for the concentration of microorganisms, (reference value step increase of 50 mg·L?1) and 0.01 days for the concentration of oxygen (reference value step increase of 0.1 mg·L?1). Fluctuations of concentrations of oxygen and microorganisms after an inlet disturbance of 5 × 103m3·d?1 are smal . Changes in the reference values of oxygen and microorganisms (increases by 10%, 20%and 30%) show satisfactory response of the system in al cases. Changes in the value of inlet wastewater flow rate disturbance (increases by 10%, 25%, 50%and 100%) are stabilized by the control system in short time. Maximum percent overshoot is also taken in consideration in all cases and the largest value is 25%which is acceptable. The proposed method with I-P controller is better for disturbance rejection and process settling times compared to the same method using PI control er. This method can substitute optimal control systems in ASP.     

Addition of activated carbon to batch activated sludge reactors in the treatment of landfill leachate and domestic wastewater

Leachate from a municipal landfill was combined with domestic wastewater and was treated in batch activated sludge systems. The effectiveness and applicability of the addition of Powdered Activated Carbon (PAC) to activated sludge reactors was investigated. Isotherm tests were carried out with PAC in order to estimate the extent of adsorption of organic matter onto PAC. Then, in activated sludge reactors COD (Chemical Oxygen Demand) removal and nitrification were studied both in the absence and presence of PAC for comparison purposes. In both cases, Oxygen Uptake Rates (OUR) were measured with respect to time in order to investigate substrate removal and change in microbial activity. Addition of PAC to activated sludge increased COD removal by removing mainly the non‐biodegradable fraction in leachate. The COD decreases in batch reactors were best expressed by a first‐order kinetic model that incorporated this non‐biodegradable leachate fraction. With added PAC, nitrification was also enhanced. But in all of the batch runs a significant accumulation of NO₂ ‐N took place, indicating that the second step of nitrification was still inhibited. © 2001 Society of Chemical Industry     

水解酸化+活性污泥法处理涂布白纸板废水

介绍了水解酸化 活性污泥法处理涂布白板纸废水系统的设计及运行情况.运行效果稳定,该工艺处理该类废水完全可行,出水达到广东省DB 44/26-2001《水污染物排放限值》标准.     

生物铁强化活性污泥法处理不同性质企业联片废水

江南某城镇工业园区集中了众多的医药、化工、磁性材料、染料、电镀等企业.这些企业所用的原料不同,生产工艺不同,产生的废水也不同.其中很多是高污染难处理的废水.该工业园区推行了一套先由企业进行一级预处理,然后进入联片污水厂集中处理的管理模式,采用先进的A/O2(生物铁强化活性污泥法 生物接触氧化法)的废水处理工艺,该处理系统经一年多的运行表明,COD、BOD、NH3-N的去除率高,出水达到GB 8978-1996《污水综合排放标准》一级标准,为工业园区联片废水处理探索了一条新路.     

高铁氧化-活性污泥耦合工艺处理甲草胺废水

研究了高铁氧化-活性污泥耦合工艺去除水中甲草胺的效能.高铁首先氧化废水中的甲草胺分子,然后进一步氧化其降解中间物.在优化工艺条件下,高铁可在10 min内完全去除40 mg/L甲草胺,但无法实现对甲草胺的完全矿化,氧化后水体中仍有大量CODCr残留.延长高铁氧化时间可提高甲草胺废水的可生化性,并降低废水对活性污泥处理能力的抑制.高铁氧化废水与市政污水按一定体积比混合后,进一步采用活性污泥工艺处理可最终实现对甲草胺的完全矿化过程.     

UASB反应器处理玉米淀粉废水稳定性研究

分析了UASB反应器稳定运行的影响因素,试验结果表明:通过对进水量的主动调整可以解决因进水浓度波动带来的影响,反应器COD容积负荷在10 kg/(m3·d)左右时,上升流速0.7 m/h是最佳值,能够承受2 kg/(m3·d)的负荷冲击,处理效率仍能保持在75%以上.     

MUCT工艺处理生活污水短程脱氮的实现及硝化菌群动态变化

采用连续流MUCT工艺处理实际生活污水,研究短程生物脱氮的实现,并采用实时荧光定量PCR方法(quantitative real time PCR,QPCR)分析全程脱氮向短程脱氮转变过程中氨氧化细菌(ammonia-oxidizing bacteria,AOB)和亚硝酸盐氧化菌(nitrite-oxidizing bacteria,NOB)的动态变化。通过降低溶解氧浓度为0.5mg·L^-1和缩短水力停留时间为6h,实现短程硝化,亚硝酸盐积累率达到90%。在短程硝化稳定运行阶段总氮去除率高达90%以上,远远大于全程阶段的74%。QPCR结果表明全程脱氮阶段水力停留时间的缩短使AOB细胞数呈现下降的趋势,NOB细胞总数稳定维持在10⁸cells·(g dried sludge)^-1。短程脱氮阶段,AOB细胞数小幅度上升,由3.17×10⁶cells·(g dried sludge)^-1增长到1.32×10⁷cells·(g dried sludge)^-1,同时AOB占全菌的比例也小幅度增长。NOB的细胞数在5.9×10⁷~1.78×10⁸cells·(g dried sludge)^-1之间波动。NOB占全菌的比例由1.44%下降到0.47%。因此,MUCT工艺处理实际生活污水的系统中NOB丰度降低及活性抑制是实现并维持短程生物脱氮的重要原因。短程脱氮运行期间由于控制低溶解氧浓度和短的水力停留时间,AOB丰度及相对含量没有显著增加,甚至下降,但不会影响氨氮和总氮的去除。     

Development of a correlation to study parameters affecting nitrification in a domestic wastewater treatment plant

BACKGROUND: Nitrification performance of an activated sludge reactor treating weak domestic wastewater was investigated for 11 months. Ammonia nitrogen removals were investigated as a function of wastewater composition and operational conditions. Backward elimination experimental design was used to determine the influence of the most important independent variables on NH₃‐N removal efficiencies. Influent ammonia and biological oxygen demand (BOD₅) concentrations, hydraulic retention time (HRT), mixed liquid suspended solids (MLSS), temperature, pH and dissolved oxygen (DO) concentration were considered as independent variables. This study aimed to find the most important parameters to describe nitrification performance. RESULTS: The presence of nitrification was confirmed by ammonia and nitrate variations throughout the reactor; ammonia oxidizing bacteria (AOB) populations were determined using a fluorescence in situ hybridization (FISH) method. MLSS concentration, influent BOD₅ concentration and temperature were found to be the most influential factors on nitrification performance. The empirical correlation using multiple linear regressions was statistically significant and produced an adjusted coefficient of multiple determinations (R²_adj) of 92.5%. CONCLUSION: Correlation provides a good understanding of the various parameters that affect the nitrification process, and could be extended to other case studies. Using these results, operators can apply proper operational strategies to maintain nitrification in wastewater treatment plants. Copyright © 2007 Society of Chemical Industry