TiO_2/EP光催化降解水体中微污染磺胺嘧啶的研究

制备了膨胀珍珠岩(EP)为载体的TiO2催化剂(TiO2/EP),对使用较为广泛的抗生素磺胺嘧啶(SDZ)进行了光催化降解研究,探讨了TiO2的负载量、溶液的初始浓度、初始pH、无机离子(HCO3-、SO42-和Cl-)和腐殖酸(HA)对SDZ降解效果的影响。结果表明:SDZ的光催化降解符合一级反应动力学方程;当TiO2最佳负载量为20 wt%,SDZ浓度为5 mg/L,pH=6.7,紫外光照射强度为1 000μW/cm2,反应时间为45 min时,SDZ的降解率达到96%;HCO3-在低浓度时能促进SDZ的光催化降解,高浓度时促进作用不明显;SO42-和Cl-对SDZ的光催化降解有轻微的抑制作用;HA对SDZ光催化降解有显著的抑制作用,浓度越高,抑制作用越强。UV-TiO2/EP是一种去除水体中微污染SDZ的有效方法。     

非水相硝基苯在含水层中的迁移释放规律

通过室内模拟实验,探讨了在非水相硝基苯污染含水层的条件下,其在含水层中的迁移及释放规律。迁移规律表明,非水相硝基苯并非在含水层中直接进行垂向迁移,而是一方面在自身重力作用下向含水层下部迁移,另一方面在地下水流的作用下随地下水同向运移,整体表现为随地下水流的侧向运移,并最终迁移至含水层底部。释放规律表明,非水相硝基苯在含水层迁移的过程中会向地下水大量释放,释放出的硝基苯在水流的作用下随地下水同向运移,污染源及迁移至含水层底部的非水相硝基苯均存在再次释放。     

利用城市污泥堆肥及建筑弃土种植麦冬研究

将污泥堆肥产品分别与建筑弃土按0%、10%、20%、30%、40%和50%(湿重)的比例配制营养土,以麦冬为例进行180 d的栽培实验,分析了营养土对麦冬生长特性、植物体内及栽培土壤中营养学指标和重金属含量的变化规律,并通过模糊综合评价方法选择营养土较佳配制方案。实验结果表明:堆肥比例在50%时麦冬生物量增加率、新生芽数及地表部分比重为最大值,在30%时纺锤体肉质数减少率为最大值;随着营养土中堆肥比例增加,麦冬体内养分含量、重金属积累量随之增加,均在50%时达到最大值;栽培土壤养分越多损失量越多,各指残留率越低,同时全磷、全氮及K含量降低率较有效磷、碱解氮小得多,Cr降低率在5.20%～8.34%之间,Zn降低率在3.27%～17.35%之间;堆肥比例在40%以上的营养土对麦冬生长效果好,但较佳配制方案为堆肥产品占20%。     

温拌沥青混合料摊铺节能减排效果的定量化研究

通过对温拌沥青混合料(WMA)和热拌沥青混合料(HMA)生产能耗值的测量和计算,对利用WMA替代HMA作为路面材料的节能效果进行了定量核算;并结合沥青路面摊铺的实际工程设计检测方案,通过实地检测,对WMA替代HWA进行路面摊铺这一重要环节的减排效果进行了定量化。测试和分析结果显示,采用适当的温拌技术,生产能耗可降低22.4%,但是提高生产环节的能源利用效率才是降耗的重要途径。对摊铺施工的实地测量表明,WMA替代HWA摊铺可使沥青烟排放降幅53.1%,一氧化碳排放降低35.4%,二氧化氮排放降低53%,二氧化硫排放降低63.1%,综合挥发性有机物化合物VOC排放降幅达56.2%。利用WMA代替HWA作为路面材料节能减排效果十分明显。     

雾化介质阻挡放电联合电晕放电对染料溶液脱色研究

实验将介质阻挡放电与电晕放电组合在一个反应器内,以靛蓝二磺酸钠溶液为实验废水,将高压电极上通入50Hz交流高压电,在常压空气中形成介质阻挡放电-电晕放电系统,放电产生的低温等离子体及其活性基团作用于染料分子。考察了电源电压、电极间距、处理时间对染料溶液脱色率和能量效率水平的影响,确定反应器工作状态为介质阻挡放电系统电极间距30mm、电晕放电系统电极间距25mm、电源电压20kV。     

Sorption kinetic characteristics of polybrominated diphenyl ethers on natural soils

Sorption kinetic characteristics of BDE-28 and BDE-47 on five natural soils with different organic carbon fractions were investigated, and could be satisfactorily described by a two (fast and slow)-compartment first-order model with the ratio of rate constants ranged from 9 to 94 times. The fast compartment made a dominant contribution (71% ∼ 94%) to the total sorption amount in the whole process, and accounted for over 90% of the increase in the total sorption amount at initial 5 h. The influence of the slow compartment on the increase in the total sorption amount became principal (above 90%) in the subsequent stage approximately from 9 h or 25 h to the apparent equilibrium at 265 h. The results proposed the different sorption behaviors of the mathematically classified compartments for BDE-28 and BDE-47, which may correspond to the different soil components, such as soil organic fractions with amorphous and condensed structures, respectively.     

低碳理念在工业园区规划环评中的应用低碳理念在工业园区规划环评中的应用

工业园区是温室气体排放的重要源头之一,工业园区规划环评应在规划的基础上,探讨如何在评价过程中通过制定合理的对策措施,促进园区低碳发展。本文分析了低碳发展理念纳入工业园区规划环评的工作重点,建议规划环评完善评价内容,在原有评价体系中融入园区温室气体排放特征、设定低碳发展评价指标、优化设计能源结构、构建低碳产业体系、低碳发展替代方案以及碳排放跟踪评价等内容,以达到规划环评指导工业园区按低碳路径发展的目的。     

高膜通量厌氧微网生物反应器处理生活污水的研究

将动态膜技术与厌氧膜生物反应器相结合,形成一体式厌氧微网生物反应器(AnFBR),用于城市生活污水的处理,研究了在高膜通量条件下,AnFBR的运行情况和对生活污水的处理效果。结果表明,AnFBR在膜通量为72 L/(m2.h)条件下可连续稳定运行40 d;系统对COD平均去除率为58.4%,对TN和NH3-N有一定的去除效果;出水SS最高为15.0 mg/L,出水中污染物粒径在10μm以下;微网动态膜对小分子物质的截留量不高,但对分子量大于1 000 kU的物质有明显的截留效果,进水中的大部分大分子物质被转化为小分子物质;AnFBR在保留了泥水分离特点的情况下还具有结构简单、膜通量高、微网过滤周期长等优点。     

Carbon dioxide and methane fluxes in the littoral zones of two lakes,east Antarctica

During the summertime of 2007/2008, carbon dioxide (CO₂) and methane (CH₄) fluxes across air–water interface were investigated in the littoral zones of Lake Mochou and Lake Tuanjie, east Antarctica, using a static chamber technique. The mean fluxes of CO₂ and CH₄ were ?70.8 mgCO₂ m^?2 h^?1 and 144.6 μgCH₄ m^?2 h^?1, respectively, in the littoral zone of Lake Mochou; The mean fluxes were ?36.9 mgCO₂ m^?2 h^?1 and 109.8 μgCH₄ m^?2 h^?1, respectively, in the littoral zone of Lake Tuanjie. Their fluxes showed large temporal and spatial dynamics. The CO₂ fluxes showed a significantly negative correlation with daily total radiation (DTR) and a weakly negative correlation with air temperature and water temperature, indicating that sunlight intensity controlled the magnitude of CO₂ fluxes from the open lakes. The CH₄ fluxes significantly correlated with local air temperature, water table and total dissolved solids (TDS), indicating that they were the predominant factors influencing CH₄ fluxes. Summertime CO₂ budgets in the littoral zones of Lake Mochou and Lake Tuanjie were estimated to be ?152.9 gCO₂ m^?2 and ?79.7 gCO₂ m^?2, respectively, and net CH₄ emissions were estimated to be 312.3 mgCH₄ m^?2 and 237.2 mgCH₄ m^?2, respectively. Our results show that shallow, open, alga-rich lakes might be strong summertime CO₂ absorbers and small CH₄ emitters during the open water in coastal Antarctica.     

Ground-level ozone in the Pearl River Delta region: Analysis of data from a recently established regional air quality monitoring network

The ambient air quality monitoring data of 2006 and 2007 from a recently established Pearl River Delta (PRD) regional air quality monitoring network are analyzed to investigate the characteristics of ground-level ozone in the region. Four sites covering urban, suburban, rural and coastal areas are selected as representatives for detailed analysis in this paper. The results show that there are distinct seasonal and diurnal cycles in ground-level ozone across the PRD region. Low ozone concentrations are generally observed in summer, while high O₃ levels are typically found in autumn. The O₃ diurnal variations in the urban areas are larger than those at the rural sites. The O₃ concentrations showed no statistically significant difference between weekend and weekdays in contrast to the findings in many other urban areas in the world. The average ozone concentrations are lower in urban areas compared to the sites outside urban centers. Back trajectories are used to show the major air-mass transport patterns and to examine the changes in ozone from the respective upwind sites to a site in the center of the PRD (Wanqingsha). The results show higher average ozone concentrations at the upwind sites in the continental and coastal air masses, but higher 1 h-max O₃ concentrations (by 8–16 ppbv) at the center PRD site under each of air-mass category, suggesting that the ozone pollution in the PRD region exhibits both regional and super-regional characteristics.