曝气生物滤池中含苦味酸废水的COD降解动力学特性

An empirical model for COD removal in a biological aerated filter (BAF) in the presence of 2,4,6-trinitrophenol (TNP) was developed, which related effluent COD to influent COD or hydraulic loading rate along the bed height. The overall reaction rate for substrate biodegradation could be described as pseudo first order. The experimental data of COD removal against reactor height were used to calculate the parameters in the empirical model. The COD concentration at different reactor height was expressed as a function of influent COD concentration and hydraulic loading rate, and , respectively, under the experimental condi-tion. The models may be used to predict the COD removal profiles along the reactor height at different hydraulic loading rates and influent COD concentration for design, selection and sizing of BAF.     

寒冷天气下新型复合式生物生态系统与曝气生物滤池组合工艺处理生活污水的协同作用(英文)

A lab-scale integrated treatment system including the novel sequence bio-ecological process (SBEP) and biological aerated filter (BAF) for a sewage mixture (chemistry laboratory wastewater and domestic sewage) was presented in this paper. The main objective of the study was to test the contribution of artificial aeration, recir-culation ratio and mass concentration of steel slag on pollutant removal in winter when the plants are dormant. It had been shown that SBEP and BAF play different roles in removing contaminants from wastewater. During the airflow experiment, the removal efficiency of COD and TP in SBEP was higher than that in BAF, whereas BAF can compensate for the deficiency of SBEP where no significant improvement on ammonium nitrogen removal is ob-served. Yet, the removal efficiencies of COD, TP and -N in SBEP could be improved apparently when differ-ent recirculation ratio or various mass concentration of steel were applied. Especially, when the airflow of 0.06 L·h 1, the recirculation ratio rate of 80% and the mass concentration of steel of 2.2-2.4 g·L 1 were applied, the highest efficiency of 94.6%, 77.9% and 80.7% for COD, TP and -N were achieved, respectively. The inte-grated treatment system of SBEP and BAF was proved to be an effective wastewater treatment technique and a bet-ter alternative to treat domestic sewage.     

厌氧／缺氧SBR反硝化除磷过程的研究

Removal of denitrifying phosphorus was verified in a laboratory anaerobic/anoxic sequencing batch reactor (A/A SBR). The results obtained demonstrated that the anaerobic/anoxic strategy can enrich the growth of denitrifying phosphorus removing bacteria (DPB) and take up phosphate under anoxic condition by using nitrate as the electron acceptor. The phosphorus removal efficiency was higher than 90% and the effluent phosphate concentration was lower than 1mg·L^-1 after the A/A SBR was operated in a steady-state. When the chemical oxygen demand(COD) of influent was lower than 180mg·L^-1, the more COD in the influent was, the higher efficiency of phosphorus removal could be attained under anoxic condition. However, simultaneous presence of carbon and nitrate would be detrimental to denitrifying phosphorus removal. Result of influence of sludge retention time (SRT) on denitrifying phosphorus removal suggested that the decrease of SRT caused a washout of DPB and consequently the enhanced biological phosphorus removal decreased with 8 days SRT. When the SRT was restored to 16 days, however, the efficiency of phosphorus removal was higher than 90%.     

Performance evaluation of a modified step-feed anaerobic/anoxic/oxic process for organic and nutrient removal

A pilot scale modified step-feed process was improved to increase nutrient(N and P)and organic removal operations from municipal wastewater.It combined the step-feed process and a method named "University of Cape Town(UCT)".The effect of nutrient ratios and inflow distribution ratios were studied.The highest uptake efficiency of 95% for chemical oxygen demand(COD)has been achieved at the inflow distribution ratio of 40/35/25.However,maximum removal efficiency obtained for total nitrogen(TN)and phosphorus at 93% and 78%,respectively.The average mixed liquor suspended solids(MLSS)was 5500 mg·L~(-1).In addition,convenient values for dissolved oxygen(DO)concentration,and p H were obtained throughout different stages.The proposed system was identified to be an appropriate enhanced biological nutrient removal process for wastewater treatment plants owing to relatively high nutrient removal,sturdy sludge settle ability and COD removal.     

Denitrification and Dephosphatation by Anaerobic/Anoxic Sequencing Batch Reactor

Removal of denitrifying phosphorus was verified in a laboratory anaerobic/anoxic sequencing batch reactor (A/A SBR). The results obtained demonstrated that the anaerobic/anoxic strategy can enrich the growth of denitrifying phosphorus removing bacteria (DPB) and take up phosphate under anoxic condition by using nitrate as the electron acceptor. The phosphorus removal efficiency was higher than 90% and the effluent phosphate concentration was lower than lmg·L-1 after the A/A SBR was operated in a steady-state. When the chemical oxygen demand(COD) of influent was lower than 180mg·L-1, the more COD in the influent was, the higher efficiency of phosphorus removal could be attained under anoxic condition. However, simultaneous presence of carbon and nitrate would be detrimental to denitrifying phosphorus removal. Result of influence of sludge retention time (SRT) on denitrifying phosphorus removal suggested that the decrease of SRT caused a washout of DPB and consequently the enhanced biological phosphorus     

复合生物反应器亚硝酸型同步硝化反硝化脱氮

Sequence hybrid biological reactor （SHBR） was proposed, and some key control parameters were investigated for nitrogen removal from wastewater by simultaneous nitrification and denitrification （SND） via nitrite. SND via nitrite was achieved in SHBR by controlling demand oxygen （DO） concentration. There was a programmed decrease of the DO from 2.50 mg·L^-1 to 0.30 mg·L^-1, and the average nitrite accumulation rate （NAR） was increased from 16.5% to 95.5% in 3 weeks. Subsequently, further increase in DO concentration to 1.50 mg·L^-1 did not destroy the partial nitrification to nitrite. The results showed that limited air flow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate. Nitrogen removal efficiency was increased with the increase in NAR, that is, NAR was increased from 60% to 90%, and total nitrogen removal efficiency was increased from 68% to 85%. The SHBR could tolerate high organic loading rate （OLR）, COD and ammonia-nitrogen removal efficiency were greater than 92% and 93.5%, respectively,, and it even operated under low DO concentration （0.5 mg·L^-1） and maintained high OLR （4.0 kg COD·m^-3·d^-1）. The presence of biofilm positively affected the activated sludge settling capability, and sludge volume index （SVI） of activated sludge in SHBR never hit more than 90 ml·L^-1 throughout the experiments.     

A2O工艺缺氧生物磷去除

A lab-scale anaerobic-anoxic-oxic （A^2O） process used to treat a synthetic brewage wastewater was investigated. The objectives of the study were to identify the existence of denitrifying phosphorus removing bacteria （DPB）, evaluate the contribution of DPB to biological nutrient removal and enhance the denitrifying phosphorus removal in A^2O bioreactors. Sludge analysis confirmed that the average anoxic P uptake accounted for approximately 70% the total amount of P uptake, and the ratio of anoxic P uptake rate to aerobic P uptake rate was 69%. In addition, nitrate concentration in the anoxic phase and different organic substrate introduced into the anaerobic phase had significant effect on the anoxic P uptake. Compared with conventional A^2O processes, good removal efficiencies of COD, phosphorus, ammonia and total nitrogen （92.3%, 95.5%, 96% and 79.5%, respectively） could be achieved in the anoxic P uptake system, and aeration energy consumption was saved 25%. By controlling the nitrate recirculation flow in the anoxic zone, anoxic P uptake could be enhanced, which solved the competition for organic substrates among poly-P organisms and denitrifiers successfully under the COD limiting conditions. Therefore, in wastewater treatment plants the control system should be applied according to the practical situation to optimize the operation.     

硅藻土颗粒在处理煤气废水活性污泥系统中的作用

Diatomite is a kind of natural low-cost mineral material. It has a number of unique physical properties and has been widely used as an adsorbent in wastewater treatment. This study was conducted to investigate the aerobic biodegradation of coal gasification wastewater with and without diatomite addition. Experimental results indicated that diatomite added in the activated sludge system could promote the biomass and also enhance the performance of the sludge settling. The average mixed-liquor volatile suspended solids (MLVSS) is increased from 4055 mg•L－1 to 4518 mg•L－1 and the average settling volume (SV) are changed only from 45.9% to 47.1%. Diatomite additive could enhance the efficiency of chemical oxygen demand (COD) and total phenols removal from the wastewater. The COD removal increased from 73.3% to near 80% and the total phenols removal increased from 81.4% to 85.8%. The mechanisms of the increase of biomass and pollutants removal may correlates to the improvement of bioavailability and sludge settlement characteristics by diatomite added. Micrograph of the sludge in the diatomite-activated sludge system indicated that the diatomite added could be the carrier of the microbe and also affect the biomass and pollutant removal.     

应用铝和铁电极电化学处理酒精废醪蒸馏废水(英文)

Electrochemical treatment of distillery spent wash was carried out using different combinations of aluminum and iron electrodes in batch mode of operation.The spent wash was characterized for various parameters as per standard method of analysis and the treatment results were analyzed in terms of chemical oxygen demand(COD) removal efficiency of the spent wash.The experiments were performed to study the effect of operating parameters such as current density,pH of the spent wash,agitation speed,electrolysis time and the distance between the electrodes on the COD removal efficiency of the spent wash.It was observed that aluminum electrodes were more suitable for treatment of distillery spent wash as compared to iron electrodes.The maximum COD removal efficiency of 81.3% was obtained with Al-Al electrodes at the current density of 0.187 A·cm-2 and pH 3 for an electrolysis time of 2 h.     

耦合内置缺氧区的氧化沟系统强化脱氮除磷的研究(英文)

A novel modified pilot scale anaerobic oxidation ditch with additional internal anoxic zones was operated experimentally, aiming to study the improvement of biological nitrogen and phosphorus removal and the effect of enhanced denitrifying phosphorus removal in the process. Under all experimental conditions, the anaerobic-oxidation ditch with additional internal anoxic zones and an internal recycle ratio of 200% had the highest nutrient removal efficiency. The effluent NH4+-N, total nitrogen (TN), PO43-P and total phosphorus (TP) contents were 1.2mg·L-1 , 13mg·L-1, 0.3mg·L-1 and 0.4mg·L-1, respectively, all met the discharge standards in China. The TN and TP removal efficiencies were remarkably improved from 37% and 50% to 65% and 88% with the presence of additional internal anoxic zones and internal recycle ratio of 200%. The results indicated that additional internal anoxic zones can optimize the utilization of available carbon source from the anaerobic outflow for denitrification. It was also found that phosphorus removal via the denitrification process was stimulated in the additional internal anoxic zones, which was beneficial for biological nitrogen and phosphorus removal when treating wastewater with a limited carbon source. However, an excess internal recycle would cause nitrite to accumulate in the system. This seems to be harmful to biological phosphorus removal.     

粉煤灰复合滤料曝气生物滤池处理污水试验研究

采用粉煤灰复合滤料曝气生物滤池(BAF)装置处理污水,研究了气水体积比、水力负荷、进水污染物负荷对COD和NH3-N去除效果的影响。结果表明,在进水COD和NH3-N的质量浓度分别为200mg/L和25mg/L时,适宜的气水体积比为10:1,COD和NH3-N的去除率能够分别达到77.93%和84.78%;适宜的水力负荷为1.01 m3/(m.2h),COD和NH3-N的去除率能够分别达到87.88%和90.01%。反应器具有较强的抗污染物冲击负荷的能力,有机负荷在1.03～3.68kg/(m.3d)时,COD去除率均保持在75%以上;当氨氮负荷在0.22～0.44kg/(m.3d)化时,NH3-N去除率均保持在85%以上。     

外加剩余污泥水解酸化液碳源时曝气生物滤池的生物脱氮性能

利用剩余污泥水解酸化液作为外加碳源研究中部曝气和底部曝气曝气生物滤池(BAF)处理低碳氮比生活污水时的生物脱氮性能。结果表明,碳源与污水投配的流量比以及是否回流对BAF生物脱氮效果影响明显,气水流量比和回流流量比对BAF生物脱氮效果有一定影响;进水NH4+-N、TN质量浓度和COD分别为43.11、45.07、29.2mg.L-1时,中部曝气BAF的NH4+-N和TN去除率分别为99.04%和78.32%,出水COD为32.4 mg.L-1;底部曝气BAF的NH4+-N和TN去除率分别为98.61%和68.99%,出水COD为28.4 mg.L-1。研究表明,BAF在2种运行方式下可获得良好的硝化与反硝化性能,且不会引起二次污染。     

曝气生物滤池处理含硝态氮废水的研究

将优选后的好氧反硝化菌用于曝气生物滤池处理含硝态氮工业废水,研究了曝气生物滤池挂膜与启动阶段的脱氮效率,并对运行参数进行优化。结果表明,系统启动16 d后,达到稳定阶段,脱氮效率达到92.3%以上,且基本无NO2--N积累,此时可认为挂膜成功;当pH为7、水力负荷低于0.671 m3.m-2.h-1、NO3--N负荷低于1.93 kg.m-3.d-1、气水体积比为8:1时,系统获得最好的脱氮效果,NO3--N的去除率最高达到96.1%,且出水中基本无NO2--N积累。     

两级复合滤料生物滤池处理洗衣废水的试验

采用两级复合滤料生物滤池进行洗衣废水的处理试验,研究了水力负荷、气水比、COD负荷、滤层厚度及生物对其处理效果的影响,结果表明两种方式运行(工况1控制滤柱Ⅰ、滤柱Ⅱ好氧,工况2控制滤柱Ⅰ厌氧、滤柱Ⅱ好氧)的最佳工况均为气水比为2∶1,水力负荷为1.4 m3/m2.h。工况1对COD平均去除率为91.3%,对LAS的平均去除率为88.4%,对TN、TP的平均去除率分别达到29.8%和39.7%;工况2对COD去除率为87.1%,对LAS的平均去除率为93.3%,对TN、TP的平均去除率分别达到48.9%和93.3%,其出水COD、LAS、TP和TN可分别达到56 mg/L、3.1 mg/L、0.5 mg/L和15.8 mg/L。     

曝气生物滤池在化工污水回用处理中的研究

利用曝气生物滤池(BAF)工艺处理化工污水处理厂外排水回用的中试研究,主要考察了BAF启动及BAF的运行参数对处理效果的影响等。研究结果表明:在10～19℃的水温条件下,用活性污泥闷曝接种,经过30多天的成功挂膜。当BAF的进水流量为4m3/h,滤料高度为2.0m,水力负荷为2～3m3/(m2·h),气水体积比为3:1时,出水的COD、SS去除率分别为74.2%、92.7%,处理效率高、出水水质稳定,可满足冷却用水的要求。     

2级竹炭曝气生物滤池处理校园污水的启动性能研究

研究了上流式2级竹炭曝气生物滤池(UBAF)处理校园生活污水的启动规律。利用2级曝气生物滤池串联的方式,采用复合式接种挂膜的方法对曝气生物滤池进行挂膜启动。设计挂膜时间为31 d,探讨了挂膜过程中COD、BOD5以及NH3-N随时间的变化规律。由于竹炭本身具有一定吸附性,因此以空白试验验证其对COD的吸附效率。结果表明,在挂膜开始的第15天,COD与BOD5的去除率均达到80%以上,进一步以NH3-N含量变化研究,其去除率达到70%以上。表明此时曝气生物滤池挂膜启动成功。     

生物絮凝吸附与曝气生物滤池组合工艺处理生活污水

针对曝气生物滤池容易堵塞和进水中COD不宜太高的问题,而生物絮凝吸附工艺对进水中SS和COD有着较好的去除效果,提出了生物絮凝吸附与曝气生物滤池的组合工艺处理生活污水。试验表明,生物絮凝吸附能较好的去除水中的颗粒性物质、悬浮性物质和有机物,其对SS的去除率达到了69%,对COD的去除达到了61.8%,减少了后续曝气生物滤池进水的SS和COD。组合工艺对COD的平均去除率为93.7%,对氨氮的平均去除率为93.6%,总的出水SS几乎为零。在无外加碳源的情况下对TN的去除效果不好,在C/N=5时,出水的ρ(TN)≤2 mg/L,其总的平均去除率达到了95.35%。整个系统对磷酸盐的平均去除率只有为54.9%。     

珊瑚砂BAF-活性焦吸附深度处理一级A出水研究

采用珊瑚砂曝气生物滤池(BAF)-活性焦吸附工艺深度处理GB 18918-2002一级A出水,研究其性能特点及运行效果。结果表明,珊瑚砂BAF在A/O容积比为1:1、水力负荷0.60 m^3/(m^2·h)、回流体积比200%、气水体积比5:1时获得较好的处理效果。在此工况下,组合工艺对尾水中COD、NH4^+-N、TN和TP的平均去除率分别为77.09%、88.87%、56.06%和57.22%,出水COD平均为10.18 mg/L,出水NH4^+-N、TN、TP的质量浓度分别为0.53、6.36、0.192mg/L。出水中COD、NH4^+-N和TP满足GB 3838-2002的Ⅳ类水质要求,TN满足准Ⅳ类水质要求。珊瑚砂BAF-活性焦吸附是一种能满足深度处理GB 18918-2002一级A出水要求,投资少、能耗低和设备简单的组合工艺。     

两级曝气生物滤池处理生活污水的中试研究

通过两级曝气生物滤池处理城市生活污水的中试研究,探讨气水比、水力负荷、回流比及甲醇投加量等工程控制参数对两级曝气生物滤池处理城市生活污水效果的影响,结果表明,当气水比为3：1,水力负荷为2～3m3／（m2·h）,回流比为80％,甲醇投加量为80mg／L时,两级曝气生物滤池处理效果最佳,其出水可达《城镇污水处理厂污染物排放标准》中的一级A标准。