垃圾填埋场对地下水污染的模拟研究

在对长春市某垃圾填埋场进行野外调查的基础上，于室内进行了垃圾淋滤模拟实验。分析了垃圾渗滤液污染组分的自然衰减规律，建立了垃圾填埋场地下水污染的数值模型，采用FEFLOW软件对其进行模拟和预报，并取得了较好的效果，最后提出防止和防治垃圾填埋场污染地下水的若干措施。     

生活垃圾填埋场对地下水污染的风险评价——以北京北天堂垃圾填埋场为例

以国外生活垃圾填埋场对地下水污染的风险评价方法为基础,建立了综合考虑含水层脆弱性及生活垃圾填埋场自身性质的地下水污染风险评价方法,并以北京北天堂垃圾填埋场为例.评价了当地4个生活垃圾填埋场对地下水污染的风险级别.结果表明,生活垃圾填埋场对地下水污染的风险取决于场地规模、防护情况等自身相关参数以及场地所处位置的含水层脆弱...     

垃圾填埋场渗滤液的人工湿地处理

卫生填埋是垃圾处理的主要方式之一,填埋场产生的渗滤液对地下水和地表水会产生污染,因而需要进行有效的处理。介绍了垃圾渗滤液的人工湿地处理方法,包括人工湿地的组成、污染物去除机理、影响处理效率的因素等;对人工湿地处理渗滤液的工艺和国内外应用实例进行了总结;通过与传统处理方法相比,对其经济性进行了分析。可以看出,垃圾渗滤液的人工湿地处理法有成本低、构建和运行维护费用低、处理效果比较好等优点,在我国的某些地区有一定的适用性。     

城市生活垃圾填埋场项目环境风险与防范措施初探

通过对城市生活垃圾填埋场项目的环境风险进行研究和分析，提出了垃圾填埋场的环境风险与防范措施。     

垃圾填埋场渗滤液的蒸发处理工艺

垃圾填埋场渗滤液是一种难于处理的废水。本文首先对垃圾渗滤液处理工艺所存在的问题进行分析，指出蒸发处理垃圾渗滤液是一类有发展前景的工艺，然后综述了垃圾填埋场渗滤液的蒸发处理工艺。     

广州李坑生活垃圾填埋场周围植被现状调查与影响分析

为对垃圾填埋场封场后如何进行生态恢复研究提供基础资料，对超负荷运转中的广州市李坑生活垃圾填埋场周围的植被现状进行了调查，测算了物种量、覆盖度、污染状况等。同时运用植被覆盖度、结构、物种量和相对物种量等级评价以及对Zn、Cd等6种污染物的质量指数进行了评价。结果表明，所调查填埋场场区及灌区内有轻度污染，而场外与灌区外则相对较轻或无污染。     

垃圾填埋场渗滤液的蒸发处理工艺

垃圾填埋场渗滤液是一种难于处理的废水。本文首先对垃圾渗滤液处理工艺所存在的问题进行分析 ,指出蒸发处理垃圾渗滤液是一类有发展前景的工艺 ,然后综述了垃圾填埋场渗滤液的蒸发处理工艺     

垃圾降解过程中淀粉酶活性测定条件优化

垃圾填埋场中垃圾降解初期,淀粉酶活性对于垃圾填埋场中碳素的转化过程和垃圾填埋场生物学特性的研究有重要意义,而且也可作为垃圾填埋场稳定化机制研究的重要指标之一.以模拟垃圾填埋系统的垃圾为研究对象,通过正交实验(L25(56))对淀粉酶活性的测定条件进行了优化研究.结果表明:(1)正交实验结果表明,对淀粉酶活性测定的影响大...     

基于层次分析法的坦塘垃圾填埋场适宜性评价

垃圾填埋场场址的适宜性评价是生活垃圾填埋场建设和运营的前提和基础。以湖南省永州市坦塘垃圾填埋场为例,在分析研究区的地质与水文地质条件的基础上,确定了填埋场适宜性的影响因素为填埋场规模、运输条件、环境条件、建场条件和地质条件,具体包括填埋场面积及容量、综合路况条件、对地表水体污染的可能性、地形平坦程度以及场地是否处在岩溶区等条件,明确了局部地区岩溶发育是制约其适宜性的主要因素。结合垃圾填埋场的建设情况和相关规范、标准,采用层次分析法对坦塘垃圾填埋场进行适宜性评价。评价结果表明,坦塘垃圾填埋场是一个适宜场地,评价结果与实际情况相符。     

垃圾填埋场渗滤液生物处理技术改造实例分析

综述了垃圾填埋场渗滤液的物理化学、生物、土地处理等技术。对某地已投入使用的垃圾填埋场渗滤液的生物处理设施技术改造进行了较详细的分析探讨。     

利用填埋层内生物代谢控制生活垃圾填埋场渗滤液污染

讨论了目前国内卫生填埋场运行中存在的渗滤液问题 ,分析了不同填埋结构中生物代谢环境和主要污染物的代谢途径 ,探讨了不同填埋结构中利用渗滤液回灌来控制渗滤液污染的“生物反应器型”填埋技术。     

Self-organized criticality of air pollution

In this work, we investigate the frequency-size distribution of three pollution indexes (PM₁₀, NO₂ and SO₂) in Shanghai. They are well approximated by power-law distributions, which suggest that air pollution might be a manifestation of self-organized criticality. We introduce a new numerical sandpile model with decay coefficient to reveal inherent dynamic mechanism of air pollution. Only changing the number value of decay coefficient of pollutants, this model gives a good simulation of three pollutants' statistical characteristic. This work shows that it is the self-organized criticality of the air pollutants that results in the temporal variation of air pollutant indexes and the minor air pollution sources can trigger the occurrence of large pollutant events by SOC behavior.     

管道沉砂用作雨水花园土壤改良材料的可行性

以建筑黄砂为对照,采用排水管道清通作业产生的管道沉砂作为提高土壤渗透性能的改良材料,通过模拟土柱实验考察了雨水花园对路面径流污染的控制效果.实验结果表明,在装置初始运行阶段,模拟柱中污染物的淋出浓度迅速降低,污染地下水的风险很低;当污染物淋失达到稳定时,掺加同比例管道沉砂与建筑黄砂的模拟柱在提高土壤渗透速率方面效果相近,而对COD、TP、TSS、NH4+-N、NO3--N、重金属等污染物的去除两者效果则相差不大.结果表明,以管道沉砂作为土壤改良材料,在降低南方粘性土壤地区雨水花园的建造成本、实现废弃物的再利用方面具有良好前景.     

Modeling urban air pollution in São Paulo,Brazil: sensitivity of model predicted concentrations to different turbulence parameterizations

Production and transport of urban air pollution were studied at São Paulo, Brazil, due to the importance of the megacity as source of pollutants and the flow pattern and topography of the region. An Eulerian air quality model was applied. An improved method for calculating vertical diffusivities was introduced in the model and the impact on the behavior of pollutants was analyzed. The approach includes both shear generated and buoyancy-driven turbulence in a continuous formulation that adequately represents turbulence evolution in the atmospheric boundary layer. Dispersion and transformation processes are well described by model simulations. The application of the proposed parameterization leads to increased predicted concentrations. Relative changes range from 1.2 to 2. Uncertainties in the emissions result in some disagreement between measured and simulated concentrations.     

苏州市生活垃圾两种处置方法的生命周期影响评价

采用生命周期评价的方法,比较了苏州市垃圾填埋和垃圾焚烧2种处置方法对环境的影响。研究的系统范围主要包括垃圾收集、垃圾运输、垃圾填埋或焚烧以及发电等几个部分。采用收集的垃圾组分数据,利用IPCC推荐的模型等,计算了垃圾填埋和垃圾焚烧时CO₂等气体污染物的排放量。根据对垃圾渗滤液的实测数据,计算了水污染物的排放量。环境影响评价采用日本开发的AIST-LCA Ver4计算机软件进行。计算结果表明：垃圾填埋的生态币值要大得多,可见垃圾焚烧对环境的影响比垃圾填埋的影响要小。所获得的结论较为客观地反映了对环境的影响,可以作为中国城市垃圾处置决策的参考依据。     

运用GC-MS联用技术对垃圾渗滤液中有机污染物成分的分析

通过测定垃圾填埋场渗滤液的色度、BOD5、CODCr、TOC、NH3-N、NO-2-N、NO-3-N、TKN、TP、总硬度等指标来分析渗滤液的水质特性.利用GC-MS联用技术对渗滤液中有机污染物的组分进行了鉴定,共检测出主要有机污染物63种.     

Numerical Evaluation of the Effect of Traffic Pollution on Indoor Air Quality of a Naturally Ventilated Building

Abstract

A computational fluid dynamics technique was used to evaluate the effect of traffic pollution on indoor air quality of a naturally ventilated building for various ventilation control strategies. The transport of street-level nonreactive pollutants emitted from motor vehicles through the indoor environment was simulated using the large eddy simulation (LES) of the turbulent flows and the pollutant transport equations. The numerical model developed herein was verified by available wind-tunnel measurements. Good agreement with the measured velocity and concentration data was found. Twelve sets of numerical scenario simulations for various roof- and side-vent openness and outdoor wind speeds were carried out. The effects of the air change rate, the indoor airflow pattern, and the external pollutant dispersion on indoor air quality were investigated. The control strategies of ventilation rates and paths for reducing incoming vehicle pollutants and maintaining a desirable air change rate are proposed to reduce the impact of outdoor traffic pollution during traffic rush hours. It was concluded that the windward side vent is a significant factor contributing to air change rate and indoor air quality. Air intakes on the leeward side of the building can effectively reduce the peak and average indoor concentration of traffic pollutants, but the corresponding air change rate is relatively low. Using the leeward cross-flow ventilation with the windward roof vent can effectively lower incoming vehicle pollutants and maintain a desirable air change rate during traffic rush hours.     

Numerical evaluation of the effect of traffic pollution on indoor air quality of a naturally ventilated building

A computational fluid dynamics technique was used to evaluate the effect of traffic pollution on indoor air quality of a naturally ventilated building for various ventilation control strategies. The transport of street-level nonreactive pollutants emitted from motor vehicles through the indoor environment was simulated using the large eddy simulation (LES) of the turbulent flows and the pollutant transport equations. The numerical model developed herein was verified by available wind-tunnel measurements. Good agreement with the measured velocity and concentration data was found. Twelve sets of numerical scenario simulations for various roof- and side-vent openness and outdoor wind speeds were carried out. The effects of the air change rate, the indoor airflow pattern, and the external pollutant dispersion on indoor air quality were investigated. The control strategies of ventilation rates and paths for reducing incoming vehicle pollutants and maintaining a desirable air change rate are proposed to reduce the impact of outdoor traffic pollution during traffic rush hours. It was concluded that the windward side vent is a significant factor contributing to air change rate and indoor air quality. Air intakes on the leeward side of the building can effectively reduce the peak and average indoor concentration of traffic pollutants, but the corresponding air change rate is relatively low. Using the leeward cross-flow ventilation with the windward roof vent can effectively lower incoming vehicle pollutants and maintain a desirable air change rate during traffic rush hours.     

Ambient air quality levels in Tehran, Iran, from 1988 to 1993

The objectives of this study were to describe trends in ambient air quality in Tehran between 1988 and 1993, to determine if these levels exceeded the World Health Organization (WHO) guidelines, and to discuss possible health effects related to exposure for these particular pollutants. Data were acquired from Iran's Environmental Protection Agency (IEPA) and the Ministry of Health (MH). These agencies operate five automated ambient air monitoring stations located in areas with heavy traffic. Daily samples of SO₂, NO₂, CO, total suspended particulate matter (TSM), and hydrocarbons (HC) were collected to provide 24 hour averages for each pollutant. Every three months, mean concentrations were reported to IEPA. Composite samples from all five stations were stored in a databank operated by IEPA. The ambient air quality guidelines were obtained from WHO reports. Statistical analysis was carried out using a regression model, which was designed to fit the air pollution data and take into account missing data. The results showed that there was a statistically significant upward trend in air pollution levels for all of the measured pollutants, except NO2, during the years 1988 to 1993. WHO guidelines were routinely and substantially exceeded by all pollutants except TSM. These findings suggest that as the population continues to grow, and increasing numbers of motor vehicles are driven in Tehran, there is concern for the health effects that may result from exposure to these pollutants.     

中国土壤环境污染态势及预防、控制和修复策略

在综述中国土壤环境污染态势及成因的基础上,提出了土壤环境污染的预防、控制和修复策略.指出了当前中国土壤环境污染态势严峻,表现出土壤污染范围在扩大,污染物种类在增多,出现了复合型、混合型的高风险污染区,呈现出从污灌型向与大气沉降型并重转变、城郊向农村延伸、局部向区域蔓延的趋势;体现出土壤污染与土壤酸化的叠加、多种传统污染物与新兴污染物相互混合的态势,危及粮食生产、食物质量、生态安全、人体健康以及区域可持续发展.认为以预防为主,预防、控制和修复相结合是中国在相当长时期内的土壤环境保护策略;土壤污染预防需要法律法规、评价标准、管理政策和公众参与,土壤污染控制需要发展物化控制、生物学控制及其协同控制技术,土壤污染修复需要研发工程修复技术、材料、产品与设备,建立技术规范、评价标准和管理体系,推动市场化和产业化发展.