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41.
Abstract

The process industries (specifically, energy and chemicals) are characterized by a variety of reactors and reactions to bring about successful process operations. The design of energy-related and chemical processes and their evolution is a complex process that determines the competitiveness of these industries, as well as their environmental impact. Thus, we have developed an Enviro-Energy Concept designed to facilitate sustainable industrial development. The Complete Onion Model represents a complete methodology for chemical process design and illustrates all of the requirements to achieve the best possible design within the accepted environmental standards. Currently, NOx emissions from industrial processes continue to receive maximum attention, therefore the issue problem of NOx emissions from industrial sources such as power stations and nitric acid plants is considered. The Selective Catalytic Reduction (SCR) is one of the most promising and effective commercial technologies. It is considered the Best Available Control Technology (BACT) for NOx reduction. The solution of NOx Emissions problem is either through modifying the chemical process design and/or installing an end-of-pipe technology. The degree of integration between the process design and the installed technology plays a critical role in the capital cost evaluation. Therefore, integrating process units and then optimizing the design has a vital effect on the total cost. Both the environmental regulations and the cost evaluation are the boundary constraints of the optimum solution.  相似文献   
42.
In the present study, the exposure to benzene of employees working in two filling stations (one urban and one rural) was estimated, through the method of passive sampling. Additional data (30′ measurements of benzene exposure through active sampling to employees dealing with different activities, meteorological and traffic data) were collected. The measurements campaign was performed in both summer and wintertime to determine the seasonal variation of the exposure pattern.In addition, a set of artificial neural networks (ANNs) was developed to predict benzene exposure pattern for the filling station employees based on active sampling data and the parameters related to the employees’ exposure. The quantification of the contribution of each parameter to the overall exposure pattern was also attempted.The results showed that although vapour recovery technologies are installed in the refuelling systems and benzene emissions are significantly reduced compared to the past, filling station employees are still highly exposed to benzene (52–15 μg m−3). Benzene exposure is strongly correlated to car refuelling (exposure levels up to 85 μg m−3), while activities like car washing or working in cash machine inside an office contribute to lower exposure levels (up to 44 and 24 μg m−3 respectively). In rural filling station, exposure levels were in general lower compared to the urban ones, due to the smaller amount of gasoline that was traded and the absence of any significant traffic effect or urban background concentration. The developed ANN seemed to be a promising technique in the prediction of the exposure pattern giving very good results, and the quantification of the parameters affirmed the importance of the refueling procedure to the exposure levels.  相似文献   
43.
We investigated the seasonal and spatial ozone variations in China by using three-year surface ozone observation data from the six Chinese Global Atmosphere Watch(GAW)stations and tropospheric column ozone data from satellite retrieval over the period2010–2012. It is shown that the seasonal ozone variations at these GAW stations are rather different, particularly between the western and eastern locations. Compared with western China, eastern China has lower background ozone levels. However, the Asian summer monsoon(ASM) can transport photochemical pollutants from the southern to the northern areas in eastern China, leading to a northward gradual enhancement of background ozone levels at the eastern GAW stations. Over China, the tropospheric column ozone densities peak during spring and summer in the areas that are directly and/or indirectly affected by the ASM, and the peak time lags from the south to the north in eastern China. We also investigated the regional representativeness of seasonal variations of ozone at the six Chinese GAW stations using the yearly maximum tropospheric column month as indicator.The results show that the seasonal variation characteristics of ozone revealed by the Chinese GAW stations are typical, with each station having a considerable large surrounding area with the ozone maximum occurring at the same month. Ozone variations at the GAW stations are influenced by many complex factors and their regional representativeness needs to be investigated further in a broader sense.  相似文献   
44.
The relationship between the rainwater composition on two consecutive rain days was analyzed. Logrono, a remote station in the North of Spain was chosen for the analyses. The concentration of the major ions in the rainwater of the first rain day is linearly related to the concentration of the second rain day except for those ions whose source is the soil (Ca2+ and Mg2+). These ions are related to SO4 2? and NO3 ? in the first rain day, but not in the second.  相似文献   
45.
小水电站环境影响评价中的公众参与   总被引:1,自引:0,他引:1  
吕庆华  蔡瑢 《四川环境》2004,23(2):78-79
本文分析了小水电站建设对环境影响的特殊性,阐述对其环境影响评价中的公众参与的特殊内容,提出了公众参与的三种方式:公众个人问卷调查、基层组织调查、县(市)政府公共管理部门调查。  相似文献   
46.
Within the European monitoring network (EMEP, ) several different sampling procedures for measuring the main air components have been applied. This has contributed to systematic concentration differences and a comparability problem. Since 1997 co-located experiments in 15 countries have been carried out to quantify these differences. In addition, three major measurement campaigns were organized by EMEP between 1985 and 1991. Differences among results depend on the concentration level and methods used. The decrease in SO2 concentrations over the last twenty years has placed greater demands on the methodology. Absorbing solutions methods for SO2, (H2O2 and tetrachloromercurate (TCM)) typically have higher detection limits than the reference method, which uses KOH impregnated filters. The TCM method also has problems with negative interference, especially in summertime. UV fluorescence monitors have in a few cases proven to give good results, but interferences, detection limit and poor maintenance can be problems. For NO2, many countries are using the TGS absorption solution method, which has a higher detection limit than the reference method using NaI impregnated glass sinters. The Salzmann method gives unreliable results at concentrations below 1 μgN/m3, and even at higher concentrations the uncertainty is rather unsatisfactory. The chemiluminescence monitor with molybdenum converters tends to systematically overestimate NO2 concentrations, possibly because zero-drift problems and the non-specific response to NO2. Particulate sulphate measurements in general have lower bias and uncertainties than gas and other aerosol measurements.  相似文献   
47.
铁路通车里程迅速增加,铁路中小站段随之增长。站段内污水排放达不到国家排放标准而引起的环境恶化事例屡见不鲜。作者通过现场调研和资料查询,针对中小站污水排放量小、浓度较低的特点,综合分析了厌氧生物处理系统、SBR法等几种常用铁路污水处理工艺,对铁路水处理技术的发展具有一定的指导意义。  相似文献   
48.
整合环境学院的仪器设备,建立室外气象监测站。针对设备选型和要素选择、站址选择、防雷措施等问题,提出解决办法。通过处理数据传输入库系统,建立室外气象参数的数据库,为实验教学中环境监测和空调系统设计提供具体、真实、可靠的数据。  相似文献   
49.
分析县级环境监测站质量管理的现状以及存在问题,提出加强和完善县级环境监测质量管理的对策,以期通过强化管理体系的运行管理,完善质量管理人员队伍体系,全面加强质量管理工作。  相似文献   
50.
科普宣传是防震减灾工作的重要组成部分。在传统科普宣传形式之外,如何利用大量专业地震监测台站开展科普宣传是一个重要课题。通过分析我国防震减灾科普宣传的成绩和不足,结合几年来北京市地震局地震台站开展防震减灾科普宣传实例,提炼归纳出利用地震监测台站开展科普宣传的独特优势,提出应该转变传统科普宣传思维模式,切实发挥专业地震监测台站防震减灾科普宣传的作用,并就如何加强地震监测台站的科普宣传工作提出了具体建议。  相似文献   
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