基于污水厂监测数据的反硝化脱氮影响因素分析

以污水厂长序列运行数据为基础,反推脱氮实际影响因素,开展反硝化脱氮试验。结果表明,在2019年4月前后TN出水平均浓度降低58%;受季节和污水厂升级改造影响,温度由15℃升高至25℃,混合液悬浮固体质量浓度(MLSS)由4300 mg/L增至8000 mg/L,活性污泥成分增加,脱氮效果提升;BOD 5/TN和pH值等变化相对稳定,温度、MLSS是影响该污水处理厂反硝化脱氮的主要因素;当反应温度为(25±5)℃,pH值为7.5±0.2,MLSS为4800 mg/L时,反硝化脱氮效果最佳,硝酸盐氮去除率达91%。     

反硝化除磷工艺进展及影响因素

阐述了反硝化除磷的基本机理与特点,介绍了基于反硝化除磷理论研发出的单污泥工艺和双污泥工艺流程,比较了各类工艺的优缺点,提出了相应的优化改进措施。分析了反硝化除磷系统的主要影响因素,包括碳源种类、pH值、电子受体、C/P比、污泥龄等,提出了将处于实验阶段的新型工艺投入运行、探究多因素对系统脱氮除磷的综合影响等后续研究展望。     

两级SBR工艺处理小城镇生活污水的试验研究

采用两级SBR1工艺对小城镇生活污水进行了试验研究。结果表明，先通过SBR1反应器对污水起到平衡，均化作用。再通过SBR2反应器实现污水的脱氮除磷，使出水CODcr浓度为21-43mg/L。去除率达到85%-93%；出水NH3-N浓度为3.3-9.5mg/L，去除率达到65%-81%；出水TP浓度为0.32-0.63mg/L，去除率达到87%-95%。     

回流污泥比对厌氧释磷效果影响研究

为系统研究厌氧污泥回流比对生物除磷效果的影响,本文以实际生活污水作为研究水样,研究不同污泥回流比下厌氧段对COD、N、P的去除效果,深入研究污泥回流比对生物强化除磷代谢过程的影响。结果表明,在厌氧环境中污泥回流比对NH3-N的去除没有明显影响,但对硝态氮、TP、COD的去除影响较大。最佳回流污泥比应控制在60%~80%左右,在这两个工况下,PAO释磷量能达到24.13mg/L,这样能使PAO在厌氧池有效地利用碳源,充分释磷,从而提高除磷效率,同时应控制最佳厌氧有效时间为2~3h,如果厌氧时间过长或者过短都对PAO释磷产生一定的负作用。     

上海市水体富营养化及洗涤剂中磷的影响研究

针对上海市水体污染状况进行调查研究,结果表明,上海市主要水体苏州河和黄浦江有机污染日益严重,其中苏州河TP 0.6mg/L、TN 10.06mg/L,黄浦江TP 0.23mg/L、TN 4.03mg/L,超标较严重,存在发生富营养化的条件,根据国内外经验和上海的相关资料估算,洗涤剂中的磷占总磷负荷的6.82％。     

基于比值法解析老城区河段氮磷污染特征

2013年12月—2015年2月,对南淝河老城区约4 km河段水体和主要点源的氮、磷污染物进行测定,并利用碳氮比(CODCr/TN)、氮磷比(TN/TP)、氨氮百分含量(NH3-N/TN)等主要指标对所得数据进行分析研究。结果表明,南淝河老城区段水体的氮磷污染严重,氨氮百分含量接近甚至超过50%,具有一般城市生活污水的特征;氮磷比在春夏季处于藻类适宜的生长范围(9.0TN/TP22.6);整个水体处于低碳氮比水平(碳氮比小于2.5),不利于水体的净化;主要受上游望塘污水处理厂、城市生活污水和地表径流的影响。其主要支流四里河水体的氮磷污染亦相当严重,且氮、磷污染物的输入途径一致。     

两种碳源对聚磷菌种群结构及除磷脱氮性能的影响

分别以乙酸钠和丙酸钠作为有机碳源,利用序批式反应器系统对聚磷菌进行富集培养,通过高通量测序技术和化学分析,研究两种碳源对聚磷菌种类及除磷脱氮性能的影响。结果表明：稳定状态下,两者均取得良好的除磷率（＞94%）,丙酸钠对除磷的促进作用优于乙酸钠,丙酸钠对脱氮的促进作用低于乙酸钠;在科和属的水平上,丙酸钠系统的聚磷菌丰度均高于乙酸钠系统。     

洮滆水系湖库富营养化生态风险的特点与比较

茅东水库、长荡湖、涌湖、太湖竺山湾是洮滆水系从上游到下游排列的4大典型湖库,2008年的监测分析表明,氮、磷是该水系湖库富营养化的主要污染因子,并沿流域呈加剧趋势,上下游TP质量浓度为0.081～0.296 mg/L,差异小,而TN质量浓度为0.314～5.67 mg/L,差异大,长荡湖到涌湖是洮滆水系首要污染物TN快...     

合肥市环巢湖地区种植业面源污染监测与评价

通过2016-2018年在合肥市环巢湖5个县区主要农田周边沟渠中采集水样,监测农田氮磷流失浓度,并评价该区域种植业面源污染状况。结果表明,这3年该区域种植业TN、TP流失的平均质量浓度分别为3.48 mg/L、0.602 mg/L,均高于地表水Ⅴ类水质标准。2016年与2017年TN、TP浓度差异不大,2018年较前两年TN浓度有所提高,TP浓度相比显著降低。巢湖市农田沟渠水中TP浓度高于其他县区,TN浓度相对较低;NO-3 N浓度庐江县高于其他县区;NH 3 N地区间几乎没有差异。TP和NH 3 N浓度均为秋季高于夏季,TN和NO-3 N浓度均为夏季高于秋季。     

基于DPeRS模型的淮河流域氮磷面源污染评估

采用DPeRS模型对淮河流域氮、磷面源污染空间特征进行遥感像元尺度解析,并对"十三五"《重点流域水污染防治规划》中划定的淮河流域235个控制单元进行面源污染优先控制单元分析。结果表明,淮河流域2016年TN和TP面源污染排放量分别为44. 99和2. 44万t,入河量分别为27. 72和1. 27万t;空间分布上,淮河流域的东部和南部氮、磷污染程度较为显著,北部污染程度较轻;农田径流型是淮河流域最主要的氮、磷面源污染源,均占到总污染量90%以上,是该流域氮、磷面源污染防治优先控制的污染源,对于TN指标次要影响类型为城镇地表径流,对于TP指标次要影响类型为畜禽养殖;筛选出淮河流域TN和TP面源污染优先控制单元分别为164和185个,面积占比分别为75. 3%和85. 0%。     

Planted floating bed performance in treatment of eutrophic river water

The objective of the study was to treat eutrophic river water using floating beds and to identify ideal plant species for design of floating beds. Four parallel pilot-scale units were established and vegetated with Canna indica (U1), Accords calamus (U2), Cyperus alternifolius (U3), and Vetiveria zizanioides (U4), respectively, to treat eutrophic river water. The floating bed was made of polyethylene foam, and plants were vegetated on it. Results suggest that the floating bed is a viable alternative for treating eutrophic river water, especially for inhibiting algae growth. When the influent chemical oxygen demand (COD) varied from 6.53 to 18.45 mg/L, total nitrogen (TN) from 6.82 to 12.25 mg/L, total phosphorus (TP) from 0.65 to 1.64 mg/L, and Chla from 6.22 to 66.46 g/m³, the removal of COD, TN, TP, and Chla was 15.3 %–38.4 %, 25.4 %–48.4 %, 16.1 %–42.1 %, and 29.9 %–88.1 %, respectively. Ranked by removal performance, U1 was best, followed by U2, U3, and U4. In the floating bed, more than 60 % TN and TP were removed by sedimentation; plant uptake was quantitatively of low importance with an average removal of 20.2 % of TN and 29.4 % of TP removed. The loss of TN (TP) was of the least importance. Compared with the other three, U1 exhibited better dissolved oxygen (DO) gradient distributions, higher DO levels, higher hydraulic efficiency, and a higher percentage of nutrient removal attributable to plant uptake; in addition, plant development and the volume of nutrient storage in the C. indica tissues outperformed the other three species. C. indica thus could be selected when designing floating beds for the Three Gorges Reservoir region of P. R. China.     

Estimating reference nutrient criteria for Maryland ecoregions

Management of stream nutrients is becoming increasingly important in order to protect both water quality and aquatic resources throughout the USA. Using an extensive water quality database from the long-term Maryland Biological Stream Survey (MBSS), we describe nutrient relationships to landscape characteristics as total nitrogen (TN) and total phosphorus (TP) of small-order, non-tidal streams in USEPA L2 and L3 ecoregions in Maryland and by MBSS stream order at the L2 and L3 ecoregion levels. To protect stream ecosystem integrity, preliminary reference nutrient estimates (TN and TP) as percentiles (25th of all stream reaches and 75th of stream reference reaches) for the six Maryland L3 ecoregions are: Blue Ridge TN 0.29 and 0.64 mg/L, TP 0.0065 and 0.0090 mg/L; Central Appalachians TN 0.40 and 1.0 mg/L, TP 0.0060 and 0.015 mg/L; Middle Atlantic Coastal Plains TN 0.93 and 2.5 mg/L, TP 0.094 and 0.065 mg/L; Northern Piedmont TN 1.6 and 1.8 mg/L, TP 0.010 and 0.015 mg/L; Ridge and Valley TN 0.40 and 0.98 mg/L, TP 0.0063 and 0.012 mg/L; and Southeastern Plains TN 0.33 and 0.82 mg/L, TP 0.016 and 0.042 mg/L. High levels of both TN and TP are present in many streams found in non-tidal watersheds associated with all Maryland ecoregions, but are especially elevated in the Northern Piedmont and Middle Atlantic Coastal Plain ecoregions, with the latter second-order streams (average TN?>?2.9 mg/L) significantly higher than all other ecoregion–order combinations. Across all six ecoregions, mean nutrient loading for both TN and TP was generally equivalent in first-order streams to nutrient concentrations seen in both second- and third-order streams, indicating a definite need to increase efforts in preventing nutrients from entering first-order streams. Small-order stream nutrient levels are the drivers for subsequent TN and TP inputs into the upper freshwater tidal reaches of the Chesapeake Bay, resulting in a potential risk for altered estuarine ecosystems.     

Northern Rivers Ecosystem Initiative: Nutrients and Dissolved Oxygen – Issues and Impacts

Anthropogenic inputs of nitrogen (N), phosphorus (P) and oxygen-consuming material to aquatic ecosystems can change nutrient dynamics, deplete oxygen, and change abundance and diversity of aquatic plants and animals. The Northern Rivers Ecosystem Initiative required a research and assessment program to establish the contribution of pulp mill and sewage discharges to eutrophication and depressions in dissolved oxygen (DO) in the Athabasca and Wapiti rivers of northern Alberta, Canada and examine the adequacy of existing guidelines for protecting these systems. Analysis of long-term data showed that total N (TN) and total P (TP) concentrations in exposed river reaches exceeded concentrations in reference reaches by ≤ 2 times for the Athabasca River, and by 9.6 (TP) and 2.6 (TN) times for the Wapiti River. Results from nutrient limitation experiments conducted in situ and in mesocosms showed that benthic algal production was nutrient sufficient downstream of pulp mill discharges but constrained in upper river reaches by insufficient P (Athabasca River) or N + P (Wapiti River). Dissolved oxygen (DO) concentrations in both rivers declined during winter such that median concentrations in the Athabasca River 945 km downstream of the headwaters were approximately 8 mg L⁻¹ in mid-February. Although water column DO rarely approached the guideline of 6.5 mg L⁻¹, DO studies undertaken in the Wapiti River showed that pore water DO often failed to meet this guideline and could not be predicted from water column DO. Results from this integrated program of monitoring and experimentation have improved understanding of the interactions between nutrients, DO and aquatic ecosystem productivity and resulted in recommendations for revisions to nutrient and DO guidelines for these northern rivers.The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.     

Stream water nutrient enrichment in a mixed-use watershed

Eutrophic conditions, in both saline and freshwater systems, result from nutrient export from upstream watersheds. The objective of this study was to quantify the surface runoff losses of nitrate-nitrogen (NO?-N), total nitrogen (TN), dissolved reactive phosphorus (DRP), and total phosphorus (TP) resulting from prevailing practices on a managed golf course. Inflow and outflow discharge waters on a sub-area of Northland Country Club (NCC) located in Duluth, Minnesota were measured for both quantity and quality from April through November from 2003 to 2008. Nutrient losses were detectable throughout the year, had a seasonal trend, and routinely exceeded recommended levels to minimize eutrophication. The median outflow TN concentration (1.04 mg L?1) was significantly greater (p < 0.05) than the median inflow (0.81 mg L?1) concentration. Similarly, the median outflow TP concentration (0.03 mg L?1) was significantly greater (p < 0.05) than the median inflow concentration (0.02 mg L?1). Maximum recorded concentrations during the study period were 1.9 mg L?1 NO?-N, 3.93 mg L?1 TN, 0.34 mg L?1 DRP, and 1.11 mg L?1 TP. Mean annual export coefficients at NCC were 0.7 kg ha?1 NO?-N (1.7% of applied), 4.43 kg ha?1 TN (10.7% of applied), 0.14 kg ha?1 DRP (2.6% of applied), and 0.25 kg ha?1 TP (4.6% of applied). The findings of this study highlight the need for adopting conservation practices aimed at reducing offsite nutrient transport.     

生物生态耦合技术处理农村生活污水的应用研究

在对“厌氧池+跌水充氧接触氧化池+水耕蔬菜型人工湿地”生物生态耦合技术应用于农村生活污水处理进行实证研究的基础上，进一步探讨了生物与生态处理单元各自的主要去除对象和效率，为生物生态技术的合理耦合提供了依据。结果表明：在进水COD、TN、TP质量浓度波动范围为51.20~211.12，28.29~122.12，1.26~5.97mg/L时，出水平均质量浓度为15.80，5.51，0.34mg/L，出水水质达到《城镇污水处理厂污染物排放标准（GB 18918—2002）》一级A标准。污水中COD、TN、TP的78%，85%，50%的去除是在生物处理单元完成的，而TP的达标排放还必需生态处理单元的参与。整个处理技术处理效果良好，运行费用低，适合在条件允许的农村地区推广使用。     

Phytoremediation facilitates removal of nitrogen and phosphorus from eutrophicated water and release from sediment

Phosphorus (P) fractions and the effect of phytoremediation on nitrogen and phosphorus removal from eutrophicated water and release from sediment were investigated in the eco-remediation experiment enclosures installed in the Hua-jia-chi pond (Hangzhou city, Zhejiang province, China). The main P fraction in the sediment was inorganic phosphorus (IP). For the mesotrophic sediments, IP mainly consisted of HCl-extractable P (Ca-P). The annual-average concentration of total nitrogen (TN), total phosphorus (TP) in water and the content of TN, TP in different vertical depth of sediment in the experiment enclosures with hydrophyte were always much lower than those in the control enclosure without hydrophyte and those outside of experiment enclosures. It is suggested that phytoremediation was an effective technology for N and P removal from eutrophicated water and release from sediment.     

淮南潘北矿塌陷湿地土壤退化评价

采煤带来的地面塌陷是极为重要的新生环境地质问题。以淮南潘北矿塌陷湿地为研究区域,其总氮(TN)含量平均水平为1.04g/kg,总磷(TP)含量平均水平为425mg/kg,在空间分布上均有从非季节性积水区向季节性积水区递减的趋势。土壤理化性质指标间总氮与有机质(SOM)含量呈极显著正向相关,与pH呈负向相关,与有效磷(AP)呈正向相关;总磷与有效磷表现为极显著相关;AP与有效钾(AK)、SOM都有很好的相关关系。通过应用相关分析和模糊数学的原理,以TN、TP、AP、AK和SOM等5个土壤肥力指标为基础,对该区域季节性积水区和非积水区土壤肥力进行数值化综合评价。季节性积水区IFI为0.463,非积水区IFI为 0.601,表明塌陷湿地形成后会加剧水域周边土壤的退化。