IAL-CHS硝化反应器好氧硝化和氮亏损作用研究

向IAL-CHS(Internal Airlift Loop with Ceramic Honeycomb Support)硝化反应器中接种外来硝化污泥,研究了反应器内氨氮去除率变化和生物相的变化以及系统内的好氧硝化效果与HRT之间的关系.此外,对此硝化反应器好氧氮亏损的试验结果发现,当总氮为77.64～108.15 mg/L,HRT为1 h时,好氧氮亏损率平均为50.03%,而且系统内的亚硝态氮和硝态氮均处于一个较低的水平.分析认为:系统内发生氮亏损的主要原因在于反应器内蜂窝陶瓷载体特殊的结构特点和运行方式.     

磁混凝与同步硝化反硝化集成系统处理城市污水

在连续流A/O流离生物膜反应器内同步硝化反硝化的研究结果基础上,基于磁混凝装置与好氧流离反应器的集成工艺,对城市污水进行脱氮除磷处理,并对磁混凝的优势和流离反应器内同步硝化反硝化特征进行了研究。结果表明,相对于常规混凝,磁混凝的絮体结构致密、zeta电位更趋近于零、停留时间短,除磷效果好;好氧流离反应器内呈现典型的同步硝化反硝化特征,总氮和氨氮去除率分别为40%和50%。通过对集成系统的运行研究表明,该系统分段以实现氮磷的去除,易操作、实用性强、脱氮除磷效果好,利于现有污水处理设施的改进与优化。     

ABR 反应器处理食堂污水的研究

研究了ABR反应器对食堂污水中COD_(Cr)、TN的去除效果、影响因素及反应器不同隔室的作用效果。试验证明,环境温度在25～35℃,当HRT在20h,曝气量在150L/h,容积负荷在0.4～1.1kg COD_(Cr)/(m~3·d)时,COD_(Cr)去除率能高达90%;当HRT在24h,曝气量在200L/h,进水COD_(Cr)在1400mg/L时,TN去除率可达90%。反应器从启动到试验结束时,均没有出现酸化现象,出水水质稳定。     

AMBBR处理生活污水的特性及脱氮机理研究

试验采用缺氧移动床生物膜反应器处理我国南方热带亚热带地区的城市生活污水,研究了水力停留时间(HRT)、pH等因素对出水CODCr和氨氮的影响,并探索了该反应器的脱氮机理。试验结果表明,HRT为4 h时,反应器出水达到了《城镇污水处理厂污染物排放标准》(GB 18918—2002)二级标准;并且发现,当HRT≥8 h时,系统实现了短程硝化反硝化反应脱氮;而当HRT<8 h时,发现反应器脱氮以短程硝化反硝化反应和厌氧氨氧化反应同时并存现象。     

研究生论文摘要

亚硝酸型硝化的控制与反硝化除磷影响因子的研究研究生:陈鸣岐导师:任南琪(哈尔滨工业大学市政环境工程学院150090)反硝化除磷脱氮双泥工艺(Anaerobic-Anoxic/Nitrification,A2N)是以控制水体富营养化为目的的脱氮除磷新工艺,工艺中包括好氧SBR反应器和厌氧/缺氧SBR反应器。以模拟生活污水为处理对象,分别进行了厌氧/缺氧SBR间歇试验和好氧SBR的连续流试验,为下一阶段运行A2N动态试验提供运行参数的参考范围。在厌氧/缺氧SBR间歇试验中,采用厌氧/缺氧交替运行方式培养驯化反硝化聚磷污泥,结论如下:(1)当厌氧段的pH分别为8、7.5、7…     

A /O泳动床反应器脱氮性能研究

基于A/O工艺与泳动床工艺技术的联合,开发出A/O泳动床生物膜反应器.A/O泳动床系统表现出高效去除COD_(Cr)、NH_3-N和TN以及较好的抗负荷冲击能力.在HRT=12.5 h,回流比为300%,进水COD_(Cr)、NH_3-N平均浓度分别为343.4 mg/L、94.1 mg/L时,COD_(Cr)和NH3-N平均去除率分别为84.6%, 86.8%;COD_(Cr)的容积负荷与去除负荷现良好的线性关系,R~2=0.970 4;系统在较低的C/N下,TN平均去除率为70.8%.     

污水处理厂反硝化除磷研究及实践

结合苏州娄江污水处理厂生产运行实践,研究了改良型一体化交替反应池在实现良好反硝化除磷条件下的运行工况.实践表明,提高反硝化除磷的关键是要有充足的硝酸盐氮为反硝化聚磷菌(DPB)提供电子受体,当NO-2N浓度在5 mg/L以上时,可以实现较好的反硝化除磷;当SRT为12～14 d时,反硝化除磷和系统脱氮除磷效果最好,生物除磷运行成本较低.此外,进水COD/TP、好氧池DO、厌氧池MLSS以及SRT也是影响一体化反应池生物除磷的主要因素.针对雨季低负荷运行除磷效果不理想的现象,提出了相应的工况运行措施.     

硝酸盐浓度及缺氧好氧时段对反硝化聚磷诱导过程的影响

在以厌氧 缺氧 好氧方式运行的SBR反应器中 ,通过改变电子受体———硝酸盐的浓度、缺氧好氧时段 ,研究了反硝化聚磷菌的诱导条件及反硝化聚磷过程的影响因素。试验结果表明 :聚磷菌 (PAOs)包括仅以氧作为电子受体的非脱氮聚磷菌 (non DNPAOs)和既可以氧作为电子受体又可以硝酸盐为电子受体的脱氮聚磷菌 (DNPAOs)。影响脱氮聚磷菌所完成的反硝化聚磷过程的主要因素是电子受体浓度和缺氧好氧时段。     

一体化生物膜脱氮反应器介绍

根据传统好氧硝化和缺氧反硝化生物脱氮的工艺原理,开发了一体化生物膜反应器,用于生活污水的脱碳和脱氮处理。反应器分为好氧区、缓冲区和缺氧区,分别设置了不同密度的弹性纤维填料。反应器对CODCr和TN的去除率分别达96%和80%。     

生物流化床法处理城市污水处理厂污泥回流液的可行性研究

以城市污水处理厂污泥回流液为研究对象,研究生物流化床法降低污泥回流液中氮磷浓度的效果,并分析了COD/TN与COD/TP值对生物流化床脱氮除磷的影响.结果表明,COD_(Cr)浓度对脱氮影响不大,而对除磷有较大影响.在COD_(Cr)为500 mg/L,进水TN为115 mg/L时,TN的去除率最大为72.05%,此时,COD/TN值为4.35.在COD_(Cr)为480 mg/L,进水TP为11.25 mg/L时,TP的去除率最高为36.98%,此时COD/TP为42.67.生物流化床法对降低高浓度氮磷污泥回流液具有一定的去除效果,TN去除率可达56.35%,TP去除率为28.96%.     

Nitrification and denitrification in partially aerated biological aerated filter (BAF) with dual size sand media.

A 104-mm (4-inch) diameter pilot-scale biological aerated filter (BAF) with a media depth of 2.5 m (8.3 feet) was operated with an anaerobic, anoxic and oxic zone at a temperature of 23 degrees C. The medium for the anaerobic and anoxic zones was 10 mm diameter sand while the medium for the oxic zone was 5 mm diameter sand. The influent sCOD and total nitrogen concentrations in the feedwater were approximately 250 mg/L and 35 mg N/L, respectively. sCOD removal at optimum hydraulic retention time (HRT) of 3 h with recirculation rates of 100, 200 and 300% in the column was above 96%. Nitrification was found to be more than 96% for 3 h HRT at 200 and 300% recirculation. Total nitrogen removal was consistent at more than 80% for 4 and 6 h HRT at 300% recirculation. For 3 h HRT and 300% recirculation, total nitrogen removal was approximately 79%. The ammonia loading rates for maximum ammonia removed were 0.15 and 0.19 kg NH3-N/m3-day for 100 and 200% recirculation, respectively. The experimental results demonstrated that the BAF can be operated at an HRT of 3h with 200-300% recirculation rates with more than 96% removal of sCOD and ammonia and at least 75% removal of total nitrogen.     

Grey water treatment in UASB reactor at ambient temperature.

In this paper, the feasibility of grey water treatment in a UASB reactor was investigated. The batch recirculation experiments showed that a maximum total-COD removal of 79% can be obtained in grey-water treatment in the UASB reactor. The continuous operational results of a UASB reactor treating grey water at different hydraulic retention time (HRT) of 20, 12 and 8 hours at ambient temperature (14-24 degrees C) showed that 31-41% of total COD was removed. These results were significantly higher than that achieved by a septic tank (11-14%), the most common system for grey water pre-treatment, at HRT of 2-3 days. The relatively lower removal of total COD in the UASB reactor was mainly due to a higher amount of colloidal COD in the grey water, as compared to that reported in domestic wastewater. The grey water had a limited amount of nitrogen, which was mainly in particulate form (80-90%). The UASB reactor removed 24-36% and 10-24% of total nitrogen and total phosphorus, respectively, in the grey water, due to particulate nutrients removal by physical entrapment and sedimentation. The sludge characteristics of the UASB reactor showed that the system had stable performance and the recommended HRT for the reactor is 12 hours.     

生态混凝土对富营养化水源地水质改善效果

考察了生态混凝土对太湖梅梁湾水源地水质改善效果。中试结果表明:生态混凝土对TN、TP、CODMn、Chla的平均去除率分别为36.1%、53.8%、22.9%、55.5%,对总藻毒素和胞外藻毒素的去除率在27.4%～38.9%之间。通过生态混凝土可使水体的富营养状况有所降低,水质等级有所提高,对富营养化水源地水质有较明显的改善。     

Enhanced removal of chemical oxygen demand, nitrogen and phosphorus using the ameliorative anoxic/anaerobic/oxic process and micro-electrolysis

Synthetic wastewater was treated using a novel system integrating the reversed anoxic/anaerobic/oxic (RAAO) process, a micro-electrolysis (ME) bed and complex biological media. The system showed superior chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) removal rates. Performance of the system was optimised by considering the influences of three major controlling factors, namely, hydraulic retention time (HRT), organic loading rate (OLR) and mixed liquor recirculation (MLR). TP removal efficiencies were 69, 87, 87 and 83% under the HRTs of 4, 8, 12 and 16 h. In contrast, HRT had negligible effects on the COD and TN removal efficiencies. COD, TN and TP removal efficiencies from synthetic wastewater were 95, 63 and 87%, respectively, at an OLR of 1.9 g/(L·d). The concentrations of COD, TN and TP in the effluent were less than 50, 15 and 1 mg/L, respectively, at the controlled MLR range of 75-100%. In this system, organics, TN and TP were primarily removed from anoxic tank regardless of the operational conditions.     

Grey water treatment in upflow anaerobic sludge blanket (UASB) reactor at different temperatures

The treatment of grey water in two upflow anaerobic sludge blanket (UASB) reactors, operated at different hydraulic retention times (HRTs) and temperatures, was investigated. The first reactor (UASB-A) was operated at ambient temperature (14-25 degrees C) and HRT of 20, 12 and 8 h, while the second reactor (UASB-30) was operated at controlled temperature of 30 degrees C and HRT of 16, 10 and 6 h. The two reactors were fed with grey water from 'Flintenbreite' settlement in Luebeck, Germany. When the grey water was treated in the UASB reactor at 30 degrees C, total chemical oxygen demand (CODt) removal of 52-64% was achieved at HRT between 6 and 16 h, while at lower temperature lower removal (31-41%) was obtained at HRT between 8 and 20 h. Total nitrogen and phosphorous removal in the UASB reactors were limited (22-36 and 10-24%, respectively) at all operational conditions. The results showed that at increasing temperature or decreasing HRT of the reactors, maximum specific methanogenic activity of the sludge in the reactors improved. As the UASB reactor showed a significantly higher COD removal (31-64%) than the septic tank (11-14%) even at low temperature, it is recommended to use UASB reactor instead of septic tank (the most common system) for grey water pre-treatment. Based on the achieved results and due to high peak flow factor, a HRT between 8 and 12 h can be considered the suitable HRT for the UASB reactor treating grey water at temperature 20-30 degrees C, while a HRT of 12-24 h can be applied at temperature lower than 20 degrees C.     

Advanced phosphorus removal for secondary effluent using a natural treatment system

Mechanisms for low concentrations phosphorus removal in secondary effluent were studied, and a process was developed using limestone filters (LF), submerged macrophyte oxidation ponds (SMOPs) and a subsurface vertical flow wetland (SVFW). Pilot scale experimental models were applied in series to investigate the advanced purification of total phosphorus (TP) in secondary effluent at the Chengjiang sewage treatment plant. With a total hydraulic residence time (HRT) of 82.52 h, the average effluent TP dropped to 0.17 mg L(-1), meeting the standard for Class III surface waters. The major functions of the LF were adsorption and forced precipitation, with a particulate phosphorus (PP) removal of 82.93% and a total dissolved phosphorus (TDP) removal of 41.07%. Oxygen-releasing submerged macrophytes in the SMOPs resulted in maximum dissolved oxygen (DO) and pH values of 11.55 mg L(-1) and 8.10, respectively. This regime provided suitable conditions for chemical precipitation of TDP, which was reduced by a further 39.29%. In the SVFW, TDP was further reduced, and the TP removal in the final effluent reached 85.08%.     

Nitrogen removal of high strength wastewater via nitritation/denitritation using a sequencing batch reactor.

The sequencing batch reactor (SBR) process concept was applied to achieve efficient ammonium removal via nitrite under both laboratory and pilot-scale conditions. Both sets of experimental results show that without pH control or carbon addition the nitritation process consistently converted approximately 50% of the ammonium from biosolids dewatering liquids to nitrite with hydraulic retention times (HRT) as short as 10 h. The results from the pilot-scale study also indicate that the selective oxidation of ammonium to nitrite is a reliable process as the accumulation of nitrate was never an issue during a 330-day trial. The SBR process concept was extended to achieve complete nitrogen removal through nitritation and denitritation in the laboratory scale. The experimental results indicate that a total reduction of 96-98% of the ammonium nitrogen from biosolids dewatering liquids (influent concentration typically 1,200 g m(-3)) was achieved with a short HRT of 1.1 d and a removal rate of 1.05 kgNm(-3)d(-1). This process concept was tested at pilot scale where the nitritation process could be started up without temperature control in a short period of time. Nitrogen removal rates up to 1.2 kgNm(-3)d(-1) at an HRT of 0.88 d have been obtained. COD to nitrogen ratios required in the pilot plant were consistently in the range 1.6-1.9 kgCOD kg(-1)N removed.     

Optimization of the performance of an integrated anaerobic-aerobic system for domestic wastewater treatment

A promising system consisting of Up-flow Anaerobic Sludge Blanket (UASB) and Down-Flow Hanging Sponge (DHS) system was investigated for removal of COD, BOD(5) fractions, ammonia and faecal coliform from domestic wastewater. The combined system was operated at different HRTs of 16, 11 and 8 h. The results indicate that increasing the total HRT from 8 to 16 h significantly (p < 0.05) improves the COD(total) and BOD(5 total) removal mainly as a result of a higher removal of COD(soluble), BOD(soluble), COD(particulate) and BOD(particulate). The main part of coarse suspended solids was removed in the UASB reactor (76.4+/-18%) and the remaining portion was adsorbed and/or enmeshed and degraded in the biomass of the DHS system. The combined system achieved a substantial reduction of total suspended solids (TSS) resulting in an average overall percentage removal of 94+/-6% (HRT = 16 h) and 89.5+/-7.8% (HRT = 8 h). Faecal coliform reduction was significantly improved when increasing the total HRT from 8 to 16 h. Residual counts of faecal coliform were 3.1 x 10(3)/100 ml at a total HRT of 16 h, and 2.8 x 10(4)/100 ml at total HRT of 8 h, corresponding to overall removal efficiency of 99.97+/-0.03 and 99.6+/-0.3% respectively. Despite the increase of ammonia concentration as a result of protein hydrolysis in the UASB reactor, a substantial removal of ammonia was achieved in the DHS system. The results obtained show that decreasing the OLR imposed to DHS system from 2.6 to 1.6 kg COD/m(3).d significantly (p < 0.05) improves the removal efficiency of ammonia by a value of 29%. However, the removal efficiency of ammonia is not further increased when decreasing the OLR from 1.6 to 1.3 kg COD/m(3).d. The discharged sludge from UASB + DHS system exerts a good settling property and partially stabilized.DHS profile results have shown that the major part of COD, BOD(5), and TSS was removed in the upper part of the system, consequently, the nitrification process was occurring in the lower part of the DHS system.     

Biological phosphorus removal with nitrite as election acceptor.

Biological phosphorus removal was studied in a sequencing batch reactor (SBR). The results showed that nitrite could be used as electron acceptor in denitrifying phosphorus removal. Feed mode of nitrite had significant influence on denitrifying phosphorus removal. Anoxic phosphorus assimilation rate could reach 10.44 mgP/gSS.h and the percentage of anoxic phosphorus assimilation amount was more than 97% with continuous feed mode. Granular sludge with denitrifying phosphorus removal activity was found in the SBR. The effects of different operational conditions, such as COD loading, settling time, HRT etc., on the formation of granules were also studied.     

水平潜流人工湿地脱氮除磷研究进展

总结了水平潜流人工湿地的脱氮除磷机理,分析了进水水质、植物、基质、温度和水力停留时间这5种影响处理效果的主要因素,从不同角度论述了提高脱氮除磷效果所采取的措施,并探讨了水平潜流人工湿地存在的局限性和发展趋势。