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371.
对GB/T 18883-2002《室内空气质量标准》的几点看法   总被引:2,自引:0,他引:2       下载免费PDF全文
介绍了GB/T18883—2002《室内空气质量标准》的特点,对标准强制执行的实施主体、项目间的相关性和可操作性进行了讨论。  相似文献   
372.
污水处理厂出水是环境中OPEs的重要来源,且污水处理厂的生物处理单元可去除部分OPEs.为了更好的研究污水处理厂工况条件,以达到优化去除宏量有机物和微量有机物的目的,良好的小试装置必不可少.本研究在实验室设计并安装了一套A2O小试装置,根据有机磷酸酯的结构特点,在进水中投加了3种代表性的有机磷酸酯.比较了小试装置中与实际工艺单元中这3种有机磷酸酯的去除规律,发现OPEs在A2O小试中的去除规律与实际工艺单元中相似,磷酸三丁氧酯(TBEP)在两种工况下去除效果均较好,总去除率分别为84.6%与83.6%,磷酸三(1-氯-2-丙基)酯(TCPP)去除效果均较差.在不同处理单元中,由于厌氧池中主要发生水解作用,TCPP在两种工况下的厌氧池中都可去除,且在A2O小试厌氧池中的去除率(57.7%)优于实际工艺(25.5%).TBEP的去除主要发生在好氧池中,且A2O小试二沉池可以有效去除TBEP(67.9%),优于实际工艺的二沉池.两种工况下,好氧池曝气强度较大,引入磷酸三(1-氯-2-丙基)酯(TCPP)不易降解,TCPP在好氧池去除效果较差.除此之外,优化了小试装置的OPEs的检测取样量保证检测的准确性.  相似文献   
373.
Greenhouse gas(GHG) emissions from oil and gas systems are an important component of the GHG emission inventory. To assess the carbon emissions from oilfield-produced water under atmospheric conditions correctly, in situ detection and simulation experiments were developed to study the natural release of GHG into the atmosphere in the Shengli Oilfield,the second largest oilfield in China. The results showed that methane(CH4) and carbon dioxide(CO2) were the primary gases released naturally from the oilfield-produced water.The atmospheric temperature and release time played important roles in determining the CH4 and CO2emissions under atmospheric conditions. Higher temperatures enhanced the carbon emissions. The emissions of both CH4 and CO2from oilfield-produced water were highest at 27°C and lowest at 3°C. The bulk of CH4 and CO2was released from the oilfield-produced water during the first release period, 0–2 hr, for each temperature, with a maximum average emission rate of 0.415 g CH4/(m3·hr) and 3.934 g CO2/(m3·hr), respectively. Then the carbon emissions at other time periods gradually decreased with the extension of time. The higher solubility of CO2 in water than CH4 results in a higher emission rate of CH4 than CO2over the same release duration. The simulation proved that oilfield-produced water is one of the potential emission sources that should be given great attention in oil and gas systems.  相似文献   
374.
对陇东地区进行社会经济条件调查,得出陇东地区内有庆阳市和平凉市两大城市,以2013年统计数据为准,庆阳市和平凉市平均人口密度分别为97人/平方千米和219人/平方千米,均高于甘肃省平均人口密度(61人/平方千米);陇东地区生产总值达947.29亿元,占甘肃省生产总值的15.11%,属经济发达地区;且陇东地区含有丰富的煤炭和石油资源;可以得知陇东地区区域人口密度高,经济发达,资源丰富。从社会经济条件分析,陇东地区不适合作为中国高放废物粘土岩地质处置库预选区。  相似文献   
375.
376.
Environmental impact assessment (EIA) is identified as an important instrument for facilitating environmental protection and sustainable development. However, since its emergence there has been a growing interest in examining its translation from theory into practice. This paper reviews the translation of mitigation measures proposed in environmental impact statements (EISs) into planning conditions at two platinum mining and processing projects along the Great Dyke of Zimbabwe. By comparing mitigation measures proposed in EISs and those included in environmental management plans (EMPs), examining views of environmental managers and local residents, as well as field observations the mitigation implementation status is verified and evaluated. Results show that 52% of mitigation measures proposed in EISs and mostly procedural are translated into planning conditions. Residents near the platinum processing plant were not satisfied with the mitigation of sulphur dioxide, dust and noise impacts on their health. The need to incorporate and enforce substantive mitigation measures in EISs and planning conditions is recommended for the future.  相似文献   
377.
A monitoring programme during 4 years (1993-1996) was established in four eutrophic marine basins along the Mediterranean coast of Alexandria (Egypt) to follow the occurrence of a newly recorded dinoflagellate Gymnodinium catenatum and ambient environmental conditions. the species achieved its massive occurrence in warm seasons at low salinity, density stratified water column and different nutrient concentrations. A simple statistical approach showed temperature and phosphate to effect its distribution. Apparently no cases of toxic effect have accompanied the occurrence of G. catenatum. the regular occurrence of the species during the 4 year survey mean the existence of its benthic resting cysts, which certainly have important implications for its distribution dynamics.  相似文献   
378.

Backcasting is a planning methodology that is particularly helpful when problems at hand are complex and when present trends are part of the problems. When applied in planning towards sustainability, backcasting can increase the likelihood of handling the ecologically complex issues in a systematic and coordinated way, and also to foresee certain changes, even from a self-beneficial point of view, of the market and increase the chances of a relatively strong economic performance. To that end, backcasting should be performed from a set of non-overlapping principles that are general enough to be helpful in the coordination of different sectors of society and in business, as well as to cover relevant aspects of sustainability. Such principles are helpful when developing reliable non-overlapping indicators for monitoring of the development when coordinating various measures from different sectors of the society or within individual firms with each other, and when handling trade-offs in a relevant way. Furthermore, the transition can benefit from being undertaken in a strategic step-by-step manner, by which such investments search for those that combine two qualities: (i) technical flexibility to serve as platforms for future investments in line with non-overlapping principles of sustainability, and (ii) good possibilities of giving relatively fast return on investment. This framework for planning is developed together with the Natural Step, a non-government organization, and in collaboration with a network of scientists and business. Examples are given from firms applying the framework.  相似文献   
379.
医疗废物焚烧处置过程中关键参数研究   总被引:4,自引:0,他引:4  
针对我国相关标准和技术规范在医疗废物焚烧处置中的问题,以控制二英、燃烧效果、残渣处置为关键目标,从二英控制机理、工况设计、设备选择和残渣处置等焚烧的关键环节进行深入分析。提出:一燃室、二燃室的最佳温度分别为850~870和1000~1200℃;烟气停留时间大于2s,但可根据实际情况延长;湍流程度的雷诺数大于1×104,当雷诺数大于5×104时,焚烧效率更高;急冷装置在180~550℃时烟气停留时间应小于1 5s,布袋除尘器最佳工作温度为120~150℃;残渣、飞灰和底渣中的w(PCDD DFs)(以TEQ计,下同)应分别小于1 0,0 3和0 5ng g。当底渣中的w(PCDD DFs)高于0 3ng g时,则当作危险废物处理。   相似文献   
380.
室内空气污染对人体健康的危害及预防   总被引:3,自引:0,他引:3  
论述了室内空气污染的主要指标,列出了沈阳市2003年的室内空气检测结果。阐明室内污染对人体尤其是对孕妇和儿童产生的危害性;并根据国家公布的室内环境标准,提出了消费者在进行室内装修时应采取的预防措施。  相似文献   
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