生物滤池串联工艺处理西洋河淀粉废水

为减少西洋河淀粉废水中大量N、P、CODCr进入洋河水库,加剧水库的富营养化,进行了 生物滤池串联工艺处理西洋河淀粉废水的研究。结果表明:系统对淀粉废水中的氨氮、总氮、总磷、 可溶性总磷、正磷酸盐、CODCr均具有较好的去除效果,去除率可分别达到57．7％、58．7％、66．8％、 65．7％、67．4％、75．2％,且对进水浓度变化具有一定的适应性。     

Onsite wastewater nitrogen reduction with expanded media and elemental sulfur biofiltration

A passive biofiltration process has been developed to enhance nitrogen removal from onsite sanitation water. The system employs an initial unsaturated vertical flow biofilter with expanded clay media (nitrification), followed in series by a horizontal saturated biofilter for denitrification containing elemental sulfur media as electron donor. A small-scale prototype was operated continuously over eight months on primary wastewater effluent with total nitrogen (TN) of 72.2 mg/L. The average hydraulic loading to the unsaturated biofilter surface was 11.9 cm/day, applied at a 30 min dosing cycle. Average effluent TN was 2.6 mg/L and average TN reduction efficiency was 96.2%. Effluent nitrogen was 1.7 mg/L as organic N, 0.93 mg/L as ammonium (NH(4)-N), and 0.03 as oxidized (NO(3) + NO(2)) N. There was no surface clogging of unsaturated media, nitrate breakthrough, or replenishment of sulfur media over eight months. Visual and microscopic examinations revealed substantially open pores with limited material accumulation on the upper surface of the unsaturated media. Material accumulation was observed at the inlet zone of the denitrification biofilter, and sulfur media exhibited surface cavities consistent with oxidative dissolution. Two-stage biofiltration is a simple and resilient system for achieving high nitrogen reductions in onsite wastewater.     

Simultaneous nitrification and de-nitrification in MBR.

Experiments have been carried out to get an understanding of the effect of DO, C/N ratio and pH on the performance of a bench scale membrane bioreactor (MBR) in simultaneous nitrification and denitrification. It was found that under the conditions of MLSS in the range of 8000-9000 mg/L and temperature of water in the MBR of 24 degrees C, influent COD and NH3-N in the range of 523-700 mg/L and 17.24-24 mg/L respectively, the removals of COD, NH3-N and TN were 98%, 99% and 60%; 96.5%, 0,98% and 75%; 96%, 95% and 92%; 90%,70% and 60% respectively at DO of 6, 3, 1 and 0.5 mg/L. It was also found that the changes in C/N ratio and pH in a certain range have a slight effect on COD removal but have significant influence on the removal of NH3-N and TN. The results showed that only under the conditions that each ecological factor was maintained relatively steadily, simultaneous nitrification and de-nitrification proceeded smoothly. It was found that when C/N ratio was 30, the influent pH 7.2, the temperature of water in MBR 24 degrees C and DO 1 mg/L, as optimum conditions, the removals of COD, NH3-N and TN were 96%, 95% and 92% respectively. In addition, mechanism research on simultaneous nitrification and de-nitrification in MBR has been conducted as well.     

Treatment of slaughterhouse plant wastewater by using a membrane bioreactor

The use of a membrane bioreactor (MBR) for removal of organic substances and nutrients from slaughterhouse plant wastewater was investigated. The chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) concentrations of slaughterhouse wastewater were found to be approximately 571 mg O2/L, 102.5 mg/L, and 16.25 mg PO4-P/L, respectively. A submerged type membrane was used in the bioreactor. The removal efficiencies for COD, total organic carbon (TOC), TP and TN were found to be 97, 96, 65, 44% respectively. The COD value of wastewater was decreased to 16 mg/L (COD discharge standard for slaughterhouse plant wastewaters is 160 mg/L). TOC was decreased to 9 mg/L (TOC discharge standard for slaughterhouse plant wastewaters is 20 mg/L). Ammonium, and nitrate nitrogen concentrations of treated effluent were 0.100 mg NH4-N/L, and 80.521 mg NO3-N/L, respectively. Slaughterhouse wastewater was successfully treated with the MBR process.     

长江下游干流水体中氮的空间分布特征

为全面了解长江下游干流氮素的含量水平,于2014年6月对长江下游干流表层、中层和底层水体中总氮(TN)、溶解性氮(TDN)、氨氮(NH₄⁺-N)的含量进行检测,分析了氮素的空间分布特征。研究结果表明:TDN是氮在长江下游干流水体中的主要形态,而且表层、中层、底层水体中氮素含量均不相同;长江下游干流水体中TN的含量范围为0.85～2.46 mg/L,表层和底层水体中TN平均含量均高于中层水体中TN的平均含量;水体中TDN的含量范围为0.72～2.08 mg/L,表层水体中TDN平均含量相对较高;水体中NH₄⁺-N的含量范围为0.13～0.75 mg/L,表层、中层和底层水体中NH₄⁺-N的含量相近;从研究区域上游至下游,TN和TDN的平均含量呈现上升的趋势;不同城市间的NH₄⁺-N平均含量波动较大。通过相关性分析还发现,TDN与叶绿素a (Chl-a)呈显著负相关, 水温(T)与叶绿素a (Chl-a)呈显著正相关,其它形态氮与水的理化性质无明显相关关系。此研究结果可作为控制长江下游干流水体中氮素污染的基础数据。     

Enhanced denitrification with external carbon sources in a biological anoxic filter

Three parallel biological anoxic filters (BaFs) were operated to investigate the denitrification kinetics of methanol, brewery wastewater and bakery wastewater. The experiment was conducted within the temperature range of 15-20 °C, with an influent nitrate and carbon dosage of 30 mg/L and 150 mg COD/L (COD: chemical oxygen demand). The denitrification efficiencies of brewery wastewater, bakery wastewater and methanol were 84, 66 and 74%, specific denitrification rates were 1.44, 1.11 and 1.24 kg NO(3)-N/m(3) d, and total nitrogen (TN) removal rates were 74, 62 and 66%, respectively. The volatile attached solid (VAS) tests reveal that methanol has the minimum net biomass yield, so it needs the least carbon to nitrogen (expressed in COD to nitrate, C/N) ratio for complete denitrification. While the brewery wastewater and bakery wastewater need higher C/N ratio to remove all nitrate nitrogen, and they both may need pretreatment to remove phosphate when used as external carbon sources.     

WRSIS系统中稻田田面水和地下排水中氮素的动态变化特征

在江苏高淳县WRSIS系统中进行田间试验,对不同氮肥施用量下稻田田面水和地下排水中氮素动态变化特性进行分析。结果表明:施肥1 d后田面水TN和NH4+-N质量浓度值达到最大,随着时间推移,质量浓度迅速下降,施肥7 d后TN质量浓度下降70%~76%,NH4+-N质量浓度下降83.5%~85.5%。田面水中ρ(NH4+-N)/ρ(TN)和ρ(NO3--N)/ρ(TN)具有相似变化规律,先升后降,且ρ(NH4+-N)/ρ(TN)显著大于ρ(NO3--N)/ρ(TN)。地下排水中氮素以NO3--N为主,施肥后NO3--N质量浓度在3.0~19.0 mg/L的范围内;NH4+-N质量浓度较低,整个生育期质量浓度都在1.1 mg/L以下。田面水和地下排水中氮素质量浓度均随着施肥量的增加而增加。施肥7 d内是防止氮素大量流失的关键时期,需要控制排水;同时减少氮肥施用量能显著减少氮素地表流失和地下渗漏损失量。     

低负荷下厌氧氨氧化处理养殖废水的启动研究

厌氧氨氧化作为新型生物脱氮技术其关键在于如何实现厌氧氨氧化反应的启动,现有研究多以模拟废水为研究对象,本文以猪场废水为对象的研究,利用ASBR为反应器,接种反硝化污泥培养厌氧氨氧化细菌,在NH+4-N与NO-2-N浓度均为100 mg/L的条件下,运行125 d,经历启动初期、过渡期、系统稳定运行期三个阶段,厌氧氨氧化反应器中NH+4-N的去除率达91.70%,NO-2-N去除率92.0%;NH+4-N的容积负荷为36.90 mg/L.d,NO-2-N的容积负荷为37.55 mg/(L.d),成功实现了厌氧氨氧化反应器的启动。该研究成果对厌氧氨氧化技术在工程实践的应用具有重要的指导意义。     

Biological nitrogen removal using bio-sorbed internal organic carbon from piggery wastewater in a post-denitrification MLE process.

Nitrogen removal from a piggery wastewater was investigated in a post-denitrification modified Lüdzack Ettinger (PDMLE) process. Overall hydraulic retention time (HRT) of the PDMLE, consisting of contact/separator (C/S), nitrification, denitrification and re-aerobic bioreactor was 10 days. 60% of the influent SCOD was separated in the C/S by contacting the return sludge with the synthetic wastewater, however, only 10% of the influent SCOD was separated from the piggery wastewater. Biosorption capacities of the synthetic wastewater and piggery wastewater were 800 and 150 mg/g-MLSS, respectively. In spite of the high organic and nitrogen load, nitrification efficiency was above 95%, and nitrification rate was about 180 mg-NH4+-N/L x day. The removed delta COD/delta nitrate ratios in the denitrification tank were 4.0 and 11.5 g-SCOD/g-nitrate, while denitrification rates were 8.4 and 2.6 mg-nitrate/day for synthetic and piggery wastewater, respectively. In the proposed PDMLE process, both bio-sorbed and bypassed organic matter could be successfully used for nitrate reduction as carbon sources and the final TN removal efficiency was as high as 95%.     

Baffled membrane bioreactor (BMBR) for advanced wastewater treatment: easy modification of existing MBRs for efficient nutrient removal.

In this study, a novel membrane bioreactor (MBR) in which nitrification and denitrification simultaneously proceed in a single reaction chamber is proposed for advanced municipal wastewater treatment. Anoxic/aerobic environments are alternatively created in the proposed MBR by inserting baffles inside the membrane chamber. The performance of the proposed baffled membrane bioreactor (BMBR) was examined at an existing municipal wastewater treatment facility based on long-term operation. Although the procedure was simple, insertion of the baffles actually created the alternative anoxic/aerobic environments in the chamber at a constant interval and showed a great improvement in the nutrient removal. The insertion did not cause any adverse effect on membrane permeability. In this study, almost complete elimination of NH4+-N was observed while around 8 mg/L of NO(3-)-N was detected in the treated water. The modification proposed in this study can immediately be applied to most existing MBRs and is highly recommended for more efficient wastewater treatment.     

Anammox bacteria enrichment and characterization from municipal activated sludge

A sustainable option for nitrogen removal is the anaerobic ammonium-oxidizing (anammox) process in which ammonium is oxidized to nitrogen gas with nitrite as electron acceptor. Application of this process, however, is limited by the availability of anammox biomass. In this study, two Brocadia-like anammox phylotypes were successfully enriched, detected and identified from an activated sludge taken from a domestic wastewater treatment plant (Minas Gerais, Brazil) employing a Sequencing Batch Reactor (SBR). The dominant phylotype was closely related to 'Candidatus Brocadia sinica', but one clone seemed to represent a novel species for which we propose the name 'Candidatus Brocadia brasiliensis'. Based on Fluorescence in situ hybridization (FISH) analysis, this enrichment led to a relative population size of 52.7% (±15.6) anammox bacteria after 6 months of cultivation. The cultivation process can be divided into three phases: phase 1 (approximately 25 days) was characterized by heterotrophic denitrification metabolism, phase 2 was the propagation phase and phase 3 (from the 87th day onwards), in which significant anammox activity was detected. A long-term performance of the SBR showed a near perfect removal of nitrite based on the influent NO(2)(-)-N concentration of 61-95 mg L(-1). The average ammonia removal efficiency was 90% with the influent NH(4)(+)-N concentration of 55-82 mg L(-1). Therefore, anammox cultivation and enrichment from activated sludge was possible under a controlled environment within 3 months.     

恒液位SBR工艺处理城市污水的研究

采用恒液位SBR工艺对城市污水处理进行实验研究。研究影响恒液位SBR工艺脱氮除磷效果的缺氧-好氧循环、沉淀时间、进水流量等因素。结果表明:在最佳工况下处理城市污水时,COD、TN、TP和NH3-N去除率分别为88.21%~91.04%、68.04%~70.45%、95.26%~96.11%和89.76%~91.17%,说明采用恒液位SBR工艺处理城市污水是可行的。     

Application of biofilm reactors to improve ammonia oxidation in low nitrogen loaded wastewater

An airlift reactor using zeolite particles as carrier material was used for the nitrification of effluents from the aquaculture industry. During the start-up the nitrogen concentration was kept around 100 mg NH4(+)-N/L to develop the nitrifying population. Later it was decreased down to around 3 mg NH4(+)-N/L and the dilution rate was increased up to 4.8 d(-1) in order to simulate the conditions in a an aquaculture waster treatment system. A nitrogen loading rate (NLR) of 535 mg NH(+)-N/m2 d was fully oxidized to nitrate. Higher values of NLRs caused nitrite accumulation. A second biofilm reactor was fed with a synthetic medium containing 50 mg NH4(+)-N/L which simulated the effluents from anaerobic units treating domestic wastewater. A nitrogen loading rate of 400 mg NH4(+)-N/L d was oxidized into nitrate with an efficiency of 60% at a dilution rate of 8 d(-1). Both biofilm systems allowed the development of a nitrifying population to treat the studied types of wastewaters.     

土壤过滤系统处理农村生活污水的 试验研究

采用一种土壤过滤系统处理农村生活污水,考察了该工艺对CODCr、BOD5、NH3-N、全氮（TN）和全磷（TP）的去除效果。实验结果表明,当水力负荷约为0.05 m3/（m2·d）, 水力停留时间为3 d时。该土壤过滤系统对CODCr、BOD5、NH3-N、全氮（TN）和全磷（TP）的去除效果较好,平均去除率分别达到84.6%、83.3%、64.3%、59.8%和70%。出水CODCr约为18.3~42.1 mg/L,BOD5约为8.9~17.3 mg/L,NH3-N约为11.2~17.7 mg/L,TN约为21.2~31.3 mg/L,TP小于2.0 mg/L,出水水质优于农田灌溉水质标准（GB 5084—2005）。气温变化和进水污染物浓度对处理效果影响明显。总体上来讲,温度大于22 ℃时,进水污染物浓度越低处理效果越好。     

External carbon feeding strategy for enhancing nitrogen removal in SBR.

Effective method for feeding an external carbon source (ECS) in SBR was investigated to enhance denitrification based on modifying the anoxic/aerobic sub-cycle for swine wastewater treatment. The wastewater discharged from the scraper-type barns contains relatively low readily biodegradable organic. Therefore NOx-N was accumulated during repeating sub-cycle in SBR operation. When acetic acid was fed as ECS during the final sub-cycle, the maximum nitrogen removal rate was 0.22 kg N/m3/d. This was due to both less denitrification rate during the sub-cycle period and inhibition of denitrification by pH drop during the final cycle. The pH drop was caused by a large amount of ECS feeding to remove high concentration of NOx-N in the final period. To overcome these limitations and achieve higher nitrogen removal rate, the intermittent ECS feeding method with raw wastewater at every anoxic period was developed. Using the modifying ECS feeding method, the removal rate was increased to 0.45 kg N/m3/d without NOx-N accumulation.     

臭氧-活性炭-反硝化生物滤池在污水再生回用中的应用

在酒仙桥污水处理厂建立200m3/d的示范工程进行高品质再生水的生产,在二级出水强化脱氮除磷的基础上,采用臭氧(O3)-活性炭(GAC)-反硝化生物滤池(DNBF)工艺进行试验研究。经过13个月的试验证明,该工艺由于O3在脱色除臭基础上,能够强化活性炭滤池的生物多样性及活性,从而使出水CODCr能够长期稳定在30mg/L以下,NH3-N小于1mg/L。在外加碳源CH3COONa条件下,系统经DNBF后出水TN小于2mg/L。同时试验发现,为了实现经济节能及良好的污水再生效果,DNBF和O3单元在流程中的位置设置非常关键,有别于污水二级处理工艺。     

MBR工艺处理城镇污水处理厂污泥水中试研究

将平板膜组件与传统脱氮除磷工艺相结合,构建了膜生物反应器强化生物脱氮除磷中试系统,并用于处理城镇污水处理厂的污泥系统废水。结果表明,出水CODCr、BOD5、NH3—N、TN和TP的平均浓度分别为70.8 mg/L、8.7 mg/L、15.1 mg/L、29.7 mg/L和0.38 mg/L,达到或接近了《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级标准。     

Use of real-time PCR to examine the relationship between ammonia oxidizing bacterial populations and nitrogen removal efficiency in a small decentralized treatment system 'Johkasou'.

The aim of this study was to examine the relationship between ammonia oxidizing bacterial populations and biological nitrogen removal in a small on-site domestic wastewater treatment system "Johkasou". The population dynamics of ammonia oxidizing bacteria (AOB) in six full-scale advanced Johkasous was surveyed using real-time PCR assay over a period of one year. These Johkasous were selected to compare the AOB populations in different treatment performance. When the effluent NH4-N concentration was higher than 2 mg L(-1), it was difficult to meet the effluent standard of advanced Johkasous (T-N 10 mg L(-1)). In contrast, the nitrogen removal efficiency was hardly affected by nitrite oxidation and denitrification in these systems. In other words, ammonia oxidation was a rate-limiting step. Furthermore, we focused on the relationship between NH4-N loading per AOB cell and nitrogen removal. Real time PCR monitoring results demonstrated that it is important to regulate NH4-N loading per AOB cell below 210 pg cell(-1) day(-1) to meet the effluent standard of advanced Johkasou. It is considered that NH4-N loading per AOB cell is a useful parameter for determining suitable nitrogen loading and small decentralized system design.     

中水湿地去氮效果研究

以山东省平阴中水湿地为研究对象,通过对湿地水体、底泥的氨态氮(NH3-N)、硝态氮(NO3--N)沿程变化的分析,研究湿地对中水中氮(N)的去除效果。结果表明:湿地对水体中NH3-N的去除效果较好,而作为水体中N主要存在形式的NO3--N沿水流方向却呈增加趋势,微生物硝化作用强烈。底泥中总氮(TN)沿水流方向也呈增加趋势,累计效应比较明显。研究结果为湿地设计的进一步改进提供理论支持。     

Nitrite accumulation by aeration controlled in sequencing batch reactors treating domestic wastewater.

The feasibility of obtaining and keeping stable nitrite accumulation in Sequencing Batch Reactors (SBRs) treating domestic wastewater is studied. The final product of ammonium oxidation is either reproducible nitrate or nitrite depending on the aeration strategy. With the aerobic-anoxic sequence, two SBRs fed with domestic wastewater are operated in parallel. One SBR (SBR1) is controlled by the aeration control strategy, and the other SBR (SBR2) by alternate aeration control strategy. Based on the on-line indirect measurements of DO and pH, the relationship between pH (or DO) and nitrogen concentration (NH4+-N, NO(3-)-N and NO(2-)-N) is investigated. The result indicates that pH and DO can be used as control parameters for the real-time aeration control strategy to obtain nitritation in SBR treating domestic wastewater. The result of SBR1 indicates that long-term stable nitritation is possible at 32+/-1 degrees C. The result of SBR2 indicates that the aeration control strategy is necessary for nitritation during the acclimation period, because the nitrite accumulation disappears when the aeration is extended.