Remediation of saturated soil contaminated with petroleum products using air sparging with thermal enhancement

Pollutants in the form of non-aqueous phase liquids (NAPLs), such as petroleum products, pose a serious threat to the soil and groundwater. A mathematical model was derived to study the unsteady pollutant concentrations through water saturated contaminated soil under air sparging conditions for different NAPLs and soil properties. The comparison between the numerical model results and the published experimental results showed acceptable agreement. Furthermore, an experimental study was conducted to remove NAPLs from the contaminated soil using the sparging air technique, considering the sparging air velocity, air temperature, soil grain size and different contaminant properties. This study showed that sparging air at ambient temperature through the contaminated soil can remove NAPLs, however, employing hot air sparging can provide higher contaminant removal efficiency, by about 9%. An empirical correlation for the volatilization mass transfer coefficient was developed from the experimental results. The dimensionless numbers used were Sherwood number (Sh), Peclet number (Pe), Schmidt number (Sc) and several physical-chemical properties of VOCs and porous media. Finally, the estimated volatilization mass transfer coefficient was used for calculation of the influence of heated sparging air on the spreading of the NAPL plume through the contaminated soil.     

环境空气监测子站气象仪器性能状况比对研究

气象监测是环境空气质量监测的重要组成部分,在环境空气质量精细化管理中发挥着重要作用.气象部门通常采用集中送检或现场校准的方式对气象仪器性能状况进行检查,但环保部门对监测子站气象仪器的相关性能检查还处于空白状态.结合国家环境空气质量自动监测网管理现状,研究采用现场比对方式进行气象仪器性能评估.试验过程中,温度、气压比对数...     

Air pollution in California: Manufacturing vs. services

Relative to manufacturing, service activities are often considered by planners and officials to generate considerably less environmental pollution. This hypothesis is tested by means of an examination of the economic linkages of both manufacturing and service activities and of the resulting direct and indirect emissions of five air pollutants per dollar of output in the California statewide air basin and in four regional basins within the state. Overall acceptance or rejection of the hypothesis depends in part on the particular pollutant and air basin considered but, most importantly, on the judgement as to what activities are to be considered as service activities.This paper is based on research sponsored by the California Air Resources Board under Agreement A7-143-30.     

Comparative analysis of air pollution emissions by electric utilities: Public policy implications

One of the objectives of US environmental regulations was to reduce industrial air pollution emissions, especially from the electric utility industry, the major industrial air polluter. In this study, a comparative analysis of air pollution emissions from fossil-fuel-burning electric utility plants is conducted. The analysis focuses on a 12-yr period from 1975 to 1987 for three air pollutants: particulates, surfur dioxide, and nitrogen oxides. The results indicate that particulate emissions have been significantly reduced but that sulfur dioxide and nitrogen oxides are still major problems for a number of plants. Furthermore, the disparity in the performance by plants indicates that by using current technology, the industry as a whole could greatly reduce these emissions. These results have policy implication for future environmental legislation.     

太阳能光伏产业链的构建与优化分析——以锦州市为例

针对目前"十二五"规划提出发展新兴战略产业的布局,新能源成为七大新兴战略产业之一,并上升为国家重点建设项目.新能源的开发与利用体现了一国的科技水平和综合实力,太阳能成为新能源中最具发展潜力的能源.介绍了太阳能光伏产业的发展背景和理论意义,重点构建了完整的太阳能光伏产业链,阐明了产业链各个环节的内容,并结合锦州市光伏产业链实例与完整产业链进行对比,指出锦州市光伏产业链存在的问题与不足,提出了解决办法和发展建议.     

The Use of a Simple Air Quality Index in the Helsinki Area, Finland

2 (1 and 24 h), SO₂ (1 and 24 h), O₃ (1 h) and PM₁₀ (24 h). The AQI is linked to the new air quality guidelines in Finland. The AQI is based on acute health effects, but long-term effects on nature and materials are also taken into consideration. Subindices are calculated hourly for all pollutants and for a given hour the highest subindex becomes the AQI. AQI values are currently calculated for the center of Helsinki and for typical suburban areas.     

Valuation of improved air quality in Utah County,USA

A contingent valuation approach was used to estimate maximum willingness-to-pay for improved air quality in Utah County. Respondents demonstrated a high rate of concern over poor air quality and averaged a willingness-to-pay of $37 per month per household. Noniterative openended questions were used successfully. No information bias was observed but benchmark values did influence bids. Willingness-to-pay for improved air quality was large for both sexes and across all income groups, ages, and occupations.     

固相萃取-超高效液相色谱-串联质谱法测定地表水中5种磺胺类抗生素

建立了固相萃取-超高效液相色谱-串联质谱对水中5种磺胺类抗生素的测定分析方法。将水样经固相萃取后进样,经ACQUITY UPLC BEH C18(2.1 mm×100 mm,1.7μm)分离后,采用串联质谱电喷雾电离(ESI+),多反应监测(MRM)模式检测,内标法定量。方法的线性范围为5.0~100.0μg/L,线性相关系数均大于0.995,样品100倍浓缩后,检出限低至0.009μg/L;在5.0~100.0μg/L范围内,高中低3个水平的加标回收率为80.2%~90.7%,相对标准偏差(RSD)为4.3%~12.0%。该方法能够满足《国务院关于印发水污染防治行动计划的通知》限制使用抗生素等化学药品开展专项整治的需要,是一种高效、准确、灵敏度高的方法。     

太阳能光伏发电成本及展望

针对太阳能电池的昂贵发电成本,分析和预测了国内外的太阳能光伏产业链的现状与发展;指出研制高效率、低成本太阳能光伏发电系统将是今后的任务。     

美国在环境议题上的分歧及对中国的启示

美国曾经在环境保护和治理污染上做出了卓越的成绩,但是如今环境议题成为撕裂美国的重要议题。美国的共和党和民主党在环境议题上互相牵制,难以达成共识。最近,美国特朗普总统宣布退出应对气候变化的《巴黎协定》就是这种分歧的表现。但当美国1970年代开始环境立法治理污染的时候,美国社会上下和两大党之间高度一致。在此后,因为环境思想上的差异和代际转变,政党斗争、选举体制、利益集团等多方面原因,美国不同政治势力在环境议题上越发分裂。美国在环境议题上的分歧对中国如今解决环境问题有重要的启示意义:首先,现在我国社会上下一致应对环境问题的广泛共识很宝贵,应该抓住难得的机遇期,为未来环境治理积极立法,留下宝贵法治遗产。另一方面,随着人们在环境议题上的利益变得多元,中国应该在环境治理上整合各方面利益,防止中国未来的环保事业被利益集团绑架。最后,中国应该明确环境议题的概念远远大于治理污染,为未来环境事业扩展空间。     

Air assimilative capacity-based environment friendly siting of new industries--a case study of Kochi region, India

Air pollution has become a matter of grave concern, particularly in mega-cities and urban areas, where the situation is alarming and becoming more and more severe day-by-day and warrants, therefore, careful planning to facilitate future industrial development. Site selection, with the objective of minimizing adverse environmental impacts based on environmental criteria is a vital prerequisite, particularly for air polluting industries. In order to locate any air polluting industry, the assimilative capacity of the region needs to be assessed carefully and planned accordingly, so that the receiving environment is not adversely affected. Assimilative capacity of a region/airshed, widely represented through the ventilation coefficient by many researchers in the past, does not give a clear picture about the amount of emission load that can be assimilated in a given region. The ventilation coefficient, at best, can only present a broad picture about the air pollution dispersion potential (low, medium or high) of the region. A modified approach, which utilizes air quality modelling as a tool to estimate the maximum allowable emission load that a region can assimilate without violating the stipulated standards, has been used for estimating the assimilative capacity of the air environment. Details of this approach have been presented in this paper through a case study carried out for the Kochi region, located in the Kerala State of India. A variety of emission and meteorological scenarios have been considered and critical emission loads have been estimated. This approach shall provide necessary technical guidance to the environmental regulatory authorities as well as to the industries in planning environment friendly industrial development.     

Optimization of a Wind/PV Hybrid Power Generation System

This study investigates the wind and solar electricity generation availability at the Solar Energy Institute of Ege University, Izmir, Turkey. The main purpose of this study is to design an appropriate wind-PV hybrid system to cover the electricity consumption of the Institute. In order to do this, monthly average solar irradiation and wind speed data are used, which were measured, consisting of hourly records over an eight-year period from 1995–2002. Simple models were developed to determine wind, solar, and hybrid power resources per unit area. Correlations between the solar and wind power data were carried out on an hourly, daily, and monthly basis. It is shown that the hybrid system can be applied for the efficient and economic utilization of these resources.     

彭州市环境空气质量变化趋势及规律分析

“九五”期间 ,彭州市环境空气监测主要因子有二氧化硫、二氧化氮、总悬浮颗粒物、降尘和降水。市区空气中主要污染物排序依次为降尘、总悬浮颗粒物、二氧化硫、二氧化氮。其季节变化规律一般为第一季度 >第二季度 >第四季度 >第三季度。主要污染物年变化依次为降尘、总悬浮颗粒物、二氧化硫、二氧化氮 ,在“九五”期间除降尘量出现缓慢下降趋势外 ,其余 3项均不明显。