Comparison among model estimates of critical loads of acidic deposition using different sources and scales of input data

The critical load (CL) of acidic atmospheric deposition represents the load of acidity deposited from the atmosphere to the earth’s surface at which harmful acidification effects on sensitive biological receptors are thought to occur. In this study, the CL for forest soils was estimated for 27 watersheds throughout the United States using a steady-state mass balance approach based on both national and site-specific data and using different approaches for estimating base cation weathering. Results suggested that the scale and source of input data can have large effects on the calculated CL and that the most important parameter in the steady-state model used to estimate CL is base cation weathering. These results suggest that the data and approach used to estimate weathering must be robust if the calculated CL is to be useful for its intended purpose.     

莱特生物强化技术处理高浓度有机废水的中试

采用莱特生物强化技术(LTBR—Littoral BioReactor),对兰州石化公司化工园区高浓度有机废水进行了中试试验,进行了正常运行的常规标定、水量冲击标定、浓度冲击标定。结果表明:采用LTBR生物处理工艺,使用特效微生物和营养基质,可以在高COD、高含盐等不利条件下正常进行有机物降解,达到了必须将废水中的COD降至2000mg/L以下的试验要求,为处理高浓度有机化工废水的工程应用开辟了新思路。     

COD自动监测技术及应用

结合COD标准测量方法,着重分析了常见的COD自动监测技术的原理及特点,指出了不同监测技术存在的优缺点及适用范围,为开展废水污染源监控提供借鉴。     

有机改性成都粘土预处理垃圾渗滤液

以成都粘土为原料,十六烷基三甲基溴化铵(HDTMA)为改性剂制备有机改性土,并将其应用于垃圾渗滤液的预处理。采用单因素静态吸附实验,以粘土对垃圾渗滤液COD和氨氮的去除率作为考查指标,初步探究有机改性土预处理垃圾渗滤液的适宜条件;并对有机改性粘土及原土进行性能表征,初步分析其吸附机理。研究结果表明,有机土的处理效果明显优于原土,处理效果上比原土提高了1.6~2.3倍;有机土预处理垃圾渗滤液适宜条件为:投加量120 g/L、搅拌速度200 r/min、搅拌时间50 min、pH=7、静置时间为6 h。     

Using multivariate regression modeling for sampling and predicting chemical characteristics of mixed waste in old landfills

Municipal solid waste landfills pose a threat on environment and human health, especially old landfills which lack facilities for collection and treatment of landfill gas and leachate. Consequently, missing information about emission flows prevent site-specific environmental risk assessments. To overcome this gap, the combination of waste sampling and analysis with statistical modeling is one option for estimating present and future emission potentials. Optimizing the tradeoff between investigation costs and reliable results requires knowledge about both: the number of samples to be taken and variables to be analyzed.This article aims to identify the optimized number of waste samples and variables in order to predict a larger set of variables. Therefore, we introduce a multivariate linear regression model and tested the applicability by usage of two case studies. Landfill A was used to set up and calibrate the model based on 50 waste samples and twelve variables. The calibrated model was applied to Landfill B including 36 waste samples and twelve variables with four predictor variables.The case study results are twofold: first, the reliable and accurate prediction of the twelve variables can be achieved with the knowledge of four predictor variables (Loi, EC, pH and Cl). For the second Landfill B, only ten full measurements would be needed for a reliable prediction of most response variables. The four predictor variables would exhibit comparably low analytical costs in comparison to the full set of measurements. This cost reduction could be used to increase the number of samples yielding an improved understanding of the spatial waste heterogeneity in landfills.Concluding, the future application of the developed model potentially improves the reliability of predicted emission potentials. The model could become a standard screening tool for old landfills if its applicability and reliability would be tested in additional case studies.     

生物滴滤塔处理氯苯废气的工艺性能

将活性污泥培养及驯化后接种于生物滴滤塔中,挂膜启动后处理模拟氯苯废气（简称氯苯废气）,考察了生物滴滤塔在挂膜启动阶段及稳定运行阶段的性能。实验结果表明：接种41 d后生物滴滤塔成功挂膜,此时氯苯去除率稳定在90%以上;生物滴滤塔稳定运行阶段,随着进气中氯苯质量浓度由303.82 mg/m³逐渐增至1 489.05 mg/m³,氯苯去除率从85.1%降至70.1%。处理氯苯废气适宜的工艺条件为：空塔停留时间超过45 s,喷淋液流量31.8 mL/min,氯苯负荷23.97~128.01 g/（m³·h）。生物滴滤塔对喷淋液的酸性环境有较好的适应性,喷淋液pH的变化对氯苯去除率无显著影响。     

三峡库区香溪河流域非点源营养盐输出变化的试验研究

综合三峡库区香溪河流域土地利用结构和水系特点,在三大支流出口处设置常规水质监测断面,于干流响滩处设置水文控制断面,通过断面水质水量监测,利用数字滤波法解析径流多源和污染多源,研究上游来流点源和非点源营养盐输出负荷变化。结果表明：受农业非点源污染影响,TN是高岚河（0788 mg/L）＞古夫河（0712 mg/L）＞南阳河（0567 mg/L）;南阳河受磷矿企业点源输入的影响,TP是南阳河（0323 mg/L）＞高岚河（0074 mg/L）＞古夫河（0053 mg/L）;断面流量与降雨量的相关系数〖WTBX〗R〖WTBZ〗2=0720 2;TN和TP非点源年负荷输出分别占总量的61%和40%的, 20100607次降雨径流监测分析发现此次降雨汇流期间营养盐TN和TP输出的非点源贡献率分别达752%和709%;营养盐负荷主要受径流量影响,TN和TP输出负荷与流量的相关系数分别是0963 6和0978 9     

近49年中国夏季制冷度日数的变化

利用全国531个气象站1960~2008年逐日平均气温资料,分析了近49 a来我国夏季制冷度日数的变化趋势,并以浙江省为例分析了制冷度日数与夏季空调降温电力负荷的关系。主要结论如下：我国日平均温度等于或高于26℃的日数（1971~2000年平均）大于10 d,夏季有制冷需求的站点主要分布在新疆、四川盆地和太行山 巫山 雪峰山一线以东地区,以及云南干热河谷地区。1960~2008年我国黄河以北地区夏季有制冷需求的站点6~9月平均气温从20世纪90年代中期开始呈现出较明显的上升趋势,使得制冷日数和度日数都相应增加;黄河以南、南岭以北地区近49 a来6~9月平均气温线性趋势不明显,制冷度日数变化不大;南岭以南地区6~9月气温持续上升,夏季制冷度日数的增加最为显著。以浙江省为例的分析显示,制冷度日数与夏季空调降温电力负荷有很好的线性相关关系,可以用来预测降温耗电量。
     

Biodegradation of aromatic hydrocarbons by Haloarchaea and their use for the reduction of the chemical oxygen demand of hypersaline petroleum produced water

Ten halophilic Archaea (Haloarchaea) strains able to degrade aromatic compounds were isolated from five hypersaline locations; salt marshes in the Uyuni salt flats in Bolivia, crystallizer ponds in Chile and Cabo Rojo (Puerto Rico), and sabkhas (salt flats) in the Persian Gulf (Saudi Arabia) and the Dead Sea (Israel and Jordan). Phylogenetic identification of the isolates was determined by 16S rRNA gene sequence analysis. The isolated Haloarchaea strains were able to grow on a mixture of benzoic acid, p-hydroxybenzoic acid, and salicylic acid (1.5 mM each) and a mixture of the polycyclic aromatic hydrocarbons, naphthalene, anthracene, phenanthrene, pyrene and benzo[a]anthracene (0.3 mM each). Evaluation of the extent of degradation of the mixed aromatic hydrocarbons demonstrated that the isolates could degrade these compounds in hypersaline media containing 20% NaCl. The strains were shown to reduce the COD of hypersaline crude oil reservoir produced waters significantly beyond that achieved using standard hydrogen peroxide treatment alone.     

壳聚糖的物理/化学改性及其对含酚废水的处理

将壳聚糖物理改性为球形颗粒,然后在微波辐射下,球形壳聚糖与柠檬醛接枝反应,再与NaBH4还原反应,制备一种新型环保材料--物化改性壳聚糖.采用红外光谱仪(IR)、X衍射仪(XRD)、电子显微镜(SEM)和比表面测定及孔径分析仪(BET)结构表征改性壳聚糖.通过含酚制药废水的动态小柱吸附实验,研究了时间、柱高和出水流速等...