碳源及反硝化芽孢杆菌强化低C/N比景观水体的生物脱氮

实验探讨了添加碳源及投加反硝化细菌对低碳氮比景观水体生物脱氮的影响。结果表明,有机碳源及B.subtilis FS05均能显著促进实验水体的生物脱氮作用,实验水体在28℃静置72 h后,乙醇添加组的TN、氨氮、硝酸盐及亚硝酸盐的去除率分别达到了62.7%、67.0%、69.8%和29.4%,而同样条件下,B.subtilis FS05投加组的去除率分别达到了66.9%、73.4%、66.0%和82.2%。从水质变化趋势可以看出,投加B.subtilis FS05能在更短时间内完成生物脱氮过程,其中,硝酸盐和亚硝酸盐去除速率最快,分别仅需要18 h和12 h。     

电吸附对水中盐类、氨氮、COD的去除效果分析

电吸附技术作为高效、环境友好型的除盐、除氨氮技术,可应用与水的深度处理领域内。为了使污水回用达到工业用水的水质标准,对电吸附去除水中盐类、氨氮、COD的效果进行分析,结果表明,电吸附设备处理不同氨氮浓度的废水,对中低浓度的氨氮去除效果稳定,当进水氨氮浓度低于20 mg/L时,处理后出水氨氮浓度低于5 mg/L,COD浓度小于25 mg/L,达到回用标准;随着进水盐浓度的增大电吸附处理效果逐渐变差,在电导率低于2 500 μS/cm时除盐率在75%左右,氨氮去除率达到70%左右,COD去除率达到60%左右。经电吸附处理后的低氨氮浓度废水,TDS、氨氮浓度均可达到工业回用水标准。     

Factors influencing on the bioaccessibility of polybrominated diphenyl ethers in size-specific dust from air conditioner filters

Size-specific concentrations and bioaccessibility of polybrominated diphenyl ethers (PBDEs) in dust from air conditioner filters were measured, and the factors influencing the PBDE bioaccessibility were determined. Generally, the PBDE concentrations increased with decreasing dust particle size, and BDE209 (deca-BDE) was generally the predominant congener. The bioaccessibility ranged from 20.3% to 50.8% for tri- to hepta-BDEs, and from 5.1% to 13.9% for BDE209 in dust fractions of varied particle size. The bioaccessibility of most PBDE congeners decreased with increasing dust particle size. The way of being of PBDE (adsorbed to dust surface or incorporated into polymers) in dust significantly influenced the bioaccessibility. There was a significant negative correlation between the tri- to hepta-BDE bioaccessibility and organic matter (OM) contents in dust. Furthermore, tri- to hepta-BDE bioaccessibility increased with increasing polarity of OMs, while with decreasing aromaticity of OMs. The tri- to hepta-BDE bioaccessibility significantly positively correlated with the surface areas and pore volumes of dust. Using multiple linear regression analysis, it was found that the OM contents and pore volumes of dust were the most important factors to influence the tri- to hepta-BDE bioaccessibility and they could be used to estimate the bioaccessibility of tri- to hepta-BDEs according to the following equation: bioaccessibility (%) = 45.05 − 0.49 × OM% + 1.79 × pore volume. However, BDE209 bioaccessibility did not correlate to any of these factors.     

一株高效降解废水有机质耐冷菌的筛选、鉴定及特性研究

利用生物法进行污水处理已被国内外广泛使用,但由于温度影响微生物的生长和繁殖,使其成为生物污水处理效率的限制因子.本研究从污水处理厂活性污泥中分离出5株在低温4℃条件下生长良好的菌株,其中菌株DW1在4℃条件下,96 h时可将初始COD为800 mg·L-1的生活污水有机物去除率高达67.7%.结合菌落形态特征、生理生化特性以及16S r DNA序列分析,将菌株DW1初步鉴定为假单胞菌(Pseudomonas sp.).菌株DW1对COD负荷较高的污水处理效果较好;接种量为3%(体积分数)、p H为7.0时,菌株对污水COD去除率和DHA活性较高.在4℃和25℃条件下,菌株DW1均在96 h对污水COD去除率和DHA活性最高,分别为71.2%、11.35μg·m L·h-1(以TF计)和78.8%、15.11μg·m L-1·h-1(以TF计).     

Composition and source apportionment of dust fall around a natural lake

The aim of this study was to determine the source apportionment of dust fall around Lake Chini, Malaysia. Samples were collected monthly between December 2012 and March2013 at seven sampling stations located around Lake Chini. The samples were filtered to separate the dissolved and undissolved solids. The ionic compositions(NO-3, SO2-4, Cl-and NH+4) were determined using ion chromatography(IC) while major elements(K, Na, Ca and Mg) and trace metals(Zn, Fe, Al, Ni, Mn, Cr, Pb and Cd) were determined using inductively coupled plasma mass spectrometry(ICP-MS). The results showed that the average concentration of total solids around Lake Chini was 93.49 ± 16.16 mg/(m2·day). SO2-4, Na and Zn dominated the dissolved portion of the dust fall. The enrichment factors(EF) revealed that the source of the trace metals and major elements in the rain water was anthropogenic, except for Fe. Hierarchical agglomerative cluster analysis(HACA) classified the seven monitoring stations and 16 variables into five groups and three groups respectively. A coupled receptor model, principal component analysis multiple linear regression(PCA-MLR), revealed that the sources of dust fall in Lake Chini were dominated by agricultural and biomass burning(42%),followed by the earth's crust(28%), sea spray(16%) and a mixture of soil dust and vehicle emissions(14%).     

碳中和时代下我国能量自给型污水处理厂发展方向及工程实践

基于碳中和背景及污水处理可持续、低碳运行理念,分析了我国污水处理厂不同水质、工艺类型、规模等条件下的能源消耗及能源回收特点,提出了以“碳改向技术+低耗高效复合脱氮技术+污泥厌氧共消化技术+污水热能回收技术+节能降耗技术”的污水处理新模式是实现我国能源自给型污水处理厂的关键,并提出我国污水处理厂实现碳中和应分为“完全能源自给”及“能源供应工厂”两个目标.此外,对基于此背景下建设的北京某再生水厂的理论能源自给情况进行了分析,结果表明,通过节能降耗、引入外源有机物、污水源热泵回收等措施,北京某再生水厂能源自给率由12.2%分别提高至17.1%、21.6%、84.7%.     

Bioanalytical and instrumental analysis of estrogenic activities in drinking water sources from Yangtze River Delta

The estrogenic activities of source water from Yangtze River, Huaihe River, Taihu Lake and groundwater in Yangtze River Delta in the dry and wet season were determined by use of reporter gene assays based on African green monkey kidney (CV-1) cell lines. Higher estrogenic activities were observed in the dry season, and the estrogenic potentials in water samples from Taihu Lake were greater than other river basins. None of the samples from groundwater showed estrogen receptor (ER) agonist activity. The 17β-Estradiol (E2) equivalents (EEQs) of water samples in the dry season ranged from 9.41 × 10^?1 to 1.20 × 10¹ ng E2 L^?1. In the wet season, EEQs of all the water samples were below the detection limit as 9.00 × 10^?1 ng E2 L^?1 except for one sample from Huaihe River. The highest contribution of E2 was detected in Yangtze River as 99% of estrogenic activity. Nonylphenol (NP, 100% detection rate) and octylphenol (OP, 100% detection rate) might also be responsible for the estrogenic activities in water sources. Potential health risk induced by the estrogenic chemicals in source water may be posed to the residents through water drinking.     

乌鲁木齐市散煤燃烧大气污染物排放清单及时空分布特征

为研究乌鲁木齐市散煤燃烧对大气污染物的贡献情况,根据实地调研收集到的散煤燃烧活动水平数据,利用排放因子法建立2015年乌鲁木齐市散煤燃烧PM_2.5、SO₂和NO_x的排放清单,利用ArcGIS空间分析工具进行空间分布特征分析,使用蒙特卡罗方法进行不确定性分析.结果表明:2015年散煤燃烧排放PM_2.5、SO₂、NO_x分别为1.70×104、4.13×104、2.80×103 t.PM_2.5和SO₂排放的主要贡献区域为乌鲁木齐县,分别占排放总量的27.35%和26.23%,这是由于乌鲁木齐县社区居民和大棚种植耗煤量较大所致;NO_x排放的主要贡献区域为米东区,贡献率高达28.03%,这是因为米东区社区居民所用炉灶为手动炉排层燃炉灶,其排放因子较大所致.空间分布特征表明,污染物主要分布在米东区南部、沙依巴克区北部及乌鲁木齐县中部.不确定性分析表明,村庄、社区、大棚种植、商业和事业单位在95%的置信区间时不确定性分别为-69%~165%、-57%~116%、-68%~171%和-67%~165%.蒙特卡罗预测结果（平均值）高于排放清单的计算结果.研究显示,乌鲁木齐市散煤燃烧对污染物排放贡献较大,并且具有明显的季节性和区域性特征.      

Spatial PM2.5 mobile source impacts using a calibrated indicator method

Motor vehicles are major sources of fine particulate matter (PM_2.5), and the PM_2.5 from mobile vehicles is associated with adverse health effects. Traditional methods for estimating source impacts that employ receptor models are limited by the availability of observational data. To better estimate temporally and spatially resolved mobile source impacts on PM_2.5, we developed an approach based on a method that uses elemental carbon (EC), carbon monoxide (CO), and nitrogen oxide (NO_x) measurements as an indicator of mobile source impacts. We extended the original integrated mobile source indicator (IMSI) method in three aspects. First, we generated spatially resolved indicators using 24-hr average concentrations of EC, CO, and NO_x estimated at 4 km resolution by applying a method developed to fuse chemical transport model (Community Multiscale Air Quality Model [CMAQ]) simulations and observations. Second, we used spatially resolved emissions instead of county-level emissions in the IMSI formulation. Third, we spatially calibrated the unitless indicators to annually-averaged mobile source impacts estimated by the receptor model Chemical Mass Balance (CMB). Daily total mobile source impacts on PM_2.5, as well as separate gasoline and diesel vehicle impacts, were estimated at 12 km resolution from 2002 to 2008 and 4 km resolution from 2008 to 2010 for Georgia. The total mobile and separate vehicle source impacts compared well with daily CMB results, with high temporal correlation (e.g., R ranges from 0.59 to 0.88 for total mobile sources with 4 km resolution at nine locations). The total mobile source impacts had higher correlation and lower error than the separate gasoline and diesel sources when compared with observation-based CMB estimates. Overall, the enhanced approach provides spatially resolved mobile source impacts that are similar to observation-based estimates and can be used to improve assessment of health effects.

Implications: An approach is developed based on an integrated mobile source indicator method to estimate spatiotemporal PM_2.5 mobile source impacts. The approach employs three air pollutant concentration fields that are readily simulated at 4 and 12 km resolutions, and is calibrated using PM_2.5 source apportionment modeling results to generate daily mobile source impacts in the state of Georgia. The estimated source impacts can be used in investigations of traffic pollution and health.     

Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region, China

The major features of different road sections were identified. Methods quantitatively determining the ecological impact of highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper. For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health; the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals were considered.