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1.
以产业物质代谢模型和生态效率理论为基础,采用权重分析法对我国2009年38个重点行业的资源环境效率和经济效率进行了评估。研究表明:机械设备制造相关行业可作为我国产业结构调整优先发展的领域,化工、钢铁等重工业行业是我国循环经济的重点。  相似文献   

2.
采集了宁东能源化工基地核心区的146个表层土壤样品,检测了6种优控酚类污染物.运用单因子污染指数、内梅罗综合污染指数和致癌风险指数评价了酚类污染物的污染程度及健康风险.借助主成分分析和绝对主成分分数-多元线性回归受体模型,结合地统计学方法,对酚类污染物的空间分布及来源进行了分析.结果显示:2,4-二氯酚和2,4,6-三...  相似文献   

3.
H2O2脱硝工艺是面向火电厂烟气污染物控制的一种环境友好型控制技术。通过对H2O2脱硝反应机理、关键影响因素、工艺路线和经济性等方面研究,综述了国内外H2O2脱硝技术研究进展,分析了不同工艺中存在的问题,并针对存在的问题进行了探讨。  相似文献   

4.
中国与世界银行对新建火电厂的环保要求对比分析   总被引:1,自引:1,他引:0  
详细介绍了中国和世界银行对新建火电厂的不同环保要求,比较分析了电厂污染物排放中的大气(颗粒物、二氧化硫、氮氧化物)、工业废水和噪声的排放限值,对规划、新建火电厂的主要污染物控制具有参考意义。  相似文献   

5.
建立了煤基能源化工基地生态工业园区建设的指标体系,包括准入指标、行业生态化发展指标和园区生态效率指标,并对煤基能源化工基地生态化建设的方向提出了政策建议(基本原则:提高准入、总量控制、清洁生产、坚持“3R”原则),为国家对生态工业示范园区的建设开展分类指导提供决策参考。指标体系的合理性和实用性有待进一步论证和优化。  相似文献   

6.
我国能源基地与负荷中心分布不协调,决定了我国必须要进行大规模的能源转运,输煤与输电是两种主要的方式.二氧化碳捕集与封存技术是一项具有光明前景的低碳电力技术.充分考虑各种低碳要素和低碳电力技术,建立低碳效益模型,以实现对于不同能源传送方式的量化分析与灵敏度判别.算例分析部分,根据我国典型的数据对模型进行了验证,并依照现行发展趋势,对未来两者进行预测,并分析关键因素的灵敏度.  相似文献   

7.
本文将《火电厂大气污染物排放标准》(GB13223-1996)与原《燃煤电厂大气污染物排放标准》(GB13223-91)在多方面作了比较,从环保管理者的角度,分析了新标准对电力建设与污染治理产生的影响,对今后在执行新标准的过程中可能遇到的问题提出了一些见解。  相似文献   

8.
中国2001年-2010年能源与环境不和谐图像及其控制对策研究   总被引:3,自引:3,他引:3  
国内外10余个国家多年的统计结果表明能源弹性系数正常值在0.5左右,但我国“十五”期间能源弹性系数基本上均超过1,最高达1.73,说明我国“十五”期间能源与环境的发展模式不够和谐。结合2004年-2005年上报国家环保总局环境工程评估中心审查的火电项目总装机容量3.77×108kW,多种方案预测了我国“十一五”期间能源、特别是火电的发展与大气污染物排放,结果表明“十一五”期间我国能源与环境的发展仍然很难和谐。为逐步实现能源与环境的和谐发展,必须加大产业结构调整力度,限制能耗总量增长过快趋势,使我国能源弹性系数逐步恢复到正常值。  相似文献   

9.
双河联合站污水热能的回收利用   总被引:1,自引:0,他引:1  
污水热能是一种可回收利用的清洁能源,弃之浪费,用之为宝。污水热能的回收利用,可节省能源(如煤、石油、电能等),有效降低CO2、NOx、SOx及粉尘等污染物的排放量,既节能又环保。据国外资料报道,日本利用此种能源与其他热能供给系统相比,大约可节约热能34%左右;污染物排放量可消  相似文献   

10.
孙光跃 《化工环保》1995,15(3):171-174
应用等标污染负荷法对大庆三十万吨乙烯装置污水处理场的外排水进行了评价,得知外排水中的主要污染因子为COD、BOD、酚和油,并对影响其合格率的因素进行了分析,同时对如何控制污染物的流失及提高外排水中污染物的合格率提出了的建议。  相似文献   

11.
Concentrations and total quantity of cadmium (Cd), cupper (Cu),lead (Pb) and zink (Zn) were determined in biomass and soil compartments in a replicated tree species experiment with 27-yr-old stands growing on former farmland in N.E. Sweden. Sequentialextractions of soil samples were performed in order to estimate the exchangeable and an organically bound fraction of each element. The tree species included were Picea abies (L.)H. Karst., Pinus sylvestris L., Pinus contorta Dougl., Larix sibirica Ledeb., and Betula pendula Roth.Tree species influenced the rate of removal of Cu, Pb and Zn incase of stemwood harvesting, and of Cd, Cu and Zn in the case ofwhole-tree harvesting. B. pendula and P. abies had higher quantities and average concentrations of Zn in the biomass. For all species, >50% of the Zn in the stems was found in the bark. P. abies and L. sibirica had higher quantities of Cu in the biomass than the other species.P. abies and P. contorta had high quantities of Cd inthe biomass in relation to the other species. Branches and stembark contained high concentrations of Cd and Pb in relation to foliage and stemwood. Dead branches had especially high concentrations of Pb. The high accumulation rate of Zn in thebiomass of B. pendula was related to a low exchangeable amount of Zn in the A horizon. In the superficial centimeters ofthe A horizon, a depletion similar to that found for Zn was detected for Cu, whereas for Cd and Pb, no correlations were found between quantities of elements in the trees and element pools in the soil.  相似文献   

12.
Recent starch-plastic research at the National Center for Agricultural Utilization Research is reviewed and related worldwide efforts are noted. Properties of starch that influence its formulation and performance in plastics are discussed. Methods are given for preparation of starch-poly(methyl acrylate) graft copolymer, starch-poly(ethylene-co-acrylic acid), and starch-poly(ethylene-co-acrylic acid)-polyethylene plastics. Their physical properties are discussed, as is degradability by enzymes or amylolytic organisms from soil, ponds, and streams.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   

13.
Bioassessment is a useful tool to determine the impact of logging practices on the biological integrity of streams and wetlands. Measuring biota directly has an intuitive appeal for impact assessment, and biota can be superior indicators to physical or chemical characteristics because they can reflect cumulative impacts over time. Logging can affect stream and wetland biota by increasing sedimentation rates, altering hydrologic, thermal, and chemical regimes, and changing the base of food webs. Biotic impacts of logging on streams compared to wetlands probably differ, and in this paper we review some of those differences. In streams, invertebrates, fishes, amphibians, algae, and macrophytes have been used as indicators of logging impacts. In wetlands, bioassessment is just beginning to be used, and plants and birds are the most promising indicator taxa. Various best management practices (BMPs) have been developed to reduce the impacts of logging on stream and wetland biota, and we review quantitative studies that have evaluated the efficacy of some of these techniques in streams and wetlands in the eastern United States. Remarkably few studies that address the overall efficacy of BMPs in limiting biotic changes in streams and wetlands after BMP implementation have been published in scientific journals, although some work exists in reports or is unpublished. We review these works, and compile conclusions about BMP efficacy for biota from this body of research.  相似文献   

14.
Air emissions and residual ash samples were collected and analyzed during experiments of open, uncontrolled combustion of electronic waste (e-waste), simulating practices associated with rudimentary e-waste recycling operations. Circuit boards and insulated wires were handled separately to simulate processes associated with metal recovery. The average emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDD/PCDFs) were 92 ng toxic equivalency (TEQ)/kg [n = 2, relative standard deviation (RSD) = 98%] and 11 900 ng TEQ/kg (n = 3, RSD = 50%) of the initial mass of the circuit boards and insulated wire, respectively. The value for the insulated wire is about 100 times higher than that for backyard barrel burning of domestic waste. The emission concentrations of polybrominated dibenzodioxins and dibenzofurans (PBDD/PBDFs) from the combustion of circuit boards were 100 times higher than for their polychlorinated counterparts. Particulate matter (PM) sampling of the fly ash emissions indicated PM emission factors of approximately 15 and 17 g/kg of the initial mass for the circuit boards and insulated wire, respectively. Fly ash samples from both types of e-waste contained considerable amounts of several metallic elements and halogens; lead concentrations were more than 200 times the United States regulatory limits for municipal waste combustors and 20 times those for secondary lead smelters. Leaching tests of the residual bottom ash showed that lead concentrations exceeded U.S. Environmental Protection Agency landfill limits, designating this ash as a hazardous waste.  相似文献   

15.
Chemical weathering losses were calculated for two conifer stands in relation to ongoing studies on liming effects and ash amendments on chemical status, soil solution chemistry and soil genesis. Weathering losses were based on elemental depletion trends in soil profiles since deglaciation and exposure to the weathering environment. Gradients in total geochemical composition were assumed to reflect alteration over time. Study sites were Horröd and Hasslöv in southern Sweden. Both Horröd and Hasslöv sites are located on sandy loamy Weichselian till at an altitude of 85 and 190 m a.s.l., respectively. Aliquots from volume determined samples from a number of soil levels were fused with lithium metaborate, dissolved in HNO3, and analysed by ICP – AES. Results indicated highest cumulative weathering losses at Hasslöv. The weathering losses for the elements are in the following order:Si > Al > K > Na > Ca > MgTotal annual losses for Ca+Mg+K+Na, expressed in mmolc m-2 yr-1, amounted to c. 28 and 58 at Horröd and Hasslöv, respectively. Variations between study sites could not be explained by differences in bulk density, geochemistry or mineralogy. The accumulated weathering losses since deglaciation were larger in the uppermost 15 cm than in deeper B horizons for most elements studied.  相似文献   

16.
Much work has been done on gaseous emissions and leaching of nitrogenous compounds from whole soil profiles and also from soil surface measurements which are assumed to be mainly due to topsoil activity. In soils with an impervious clay subsoil, the boundary between the topsoil and subsoil may provide an interface for microbial activity, including N transformations. In this study, we investigated movement and transformations of two reactive N species (nitrate and urea) at the subsoil interface using a series of replicate, intact soil blocks, under two contrasting watering regimes. We measured fluxes in both liquid and gaseous phases and demonstrated that nitrate reaching the subsoil interface does not necessarily leach into water systems, but may denitrify immediately and could, therefore, add to atmospheric pollution through N2O production. On the other hand, ammonium reaching the subsoil interface either directly, or after mineralization, appears to be more mobile than expected and has the potential to pollute watercourses.  相似文献   

17.
We have studied particulate matter (PM) concentrations,PM10 and PM2.5, measured in an urban air qualitymonitoring network in the Helsinki Metropolitan Area during1997–1999. The data includes PM10 concentrationsmeasured at five locations (two urban traffic, one suburbantraffic, one urban background and one regional backgroundsite) and PM2.5 concentrations measured at twolocations (urban traffic and urban background sites). Theconcentrations of PM10 show a clear diurnal variation,as well as a spatial variation within the area. Bycontrast, both the spatial and temporal variation of thePM2.5 concentrations was moderate. We have analysedthe evolution of urban PM concentrations in terms of therelevant meteorological parameters in the course of oneselected peak pollution episode during 21–31 March, 1998.The meteorological variables considered included wind speedand direction, ambient temperature, precipitation, relativehumidity, atmospheric pressure at the ground level,atmospheric stability and mixing height. The elevated PMconcentrations during the 1998 March episode were clearlyrelated to conditions of high atmospheric pressure,relatively low ambient temperatures and low wind speeds inpredominantly stable atmospheric conditions. The resultsprovide indirect evidence indicating that the PM10concentrations originate mainly from local vehiculartraffic (direct emissions and resuspension), while thePM2.5 concentrations are mostly of regionally andlong-range transported origin.  相似文献   

18.
Consortia were developed for the treatment of corncobs for use as a feedstock in a biogas fermentor. The treatment of corncobs with xylanolytic consortia enhanced the production of methane and biogas. All five consortia developed produced the maximum biogas and methane at a 6% loading rate and 20 days hydraulic retention time (HRT). The maximum biogas yield of 0.59m3/kg volatile solids (VS) with a methane content of 62% was produced with the KK-10 consortium. This was apparently due to a maximum hemicellulose degradation of 88%.  相似文献   

19.
Over 7,000 lakes around Sudbury, Ontario, Canada were acidified by S deposition associated with emissions from the Sudbury metal smelters and more distant S sources. Air pollution controls have led to widespread changes in damaged Sudbury lakes, including increased pH and decreased concentrations of SO4, metals and base cations. While chemical improvements have often been substantial, many lakes are still acidified, although water quality recovery is continuing. Biological recovery has been observed in some lakes among various groups of organisms including fish, zooplankton, phytoplankton and zoobenthos. Generally, however, biological recovery is still at an early stage. Lakes around Sudbury are also showing that the recovery of acid-damaged lakes is closely linked to the effects of other major environmental stressors such as climate change, base cation depletion and UV-B irradiance. Future studies of the recovery of acid-damaged lakes around Sudbury, and in other regions, will need to consider the interactions of these and other stressors.  相似文献   

20.
Starch granules were modified with trisodium trimetaphosphate (TSTP) and characterized by P31-NMR, FTIR and DSC. Seventy-micron films were prepared from modified starch and polycaprolactone blends by solvent casting technique. Three different types of films—PCL (100% polycaprolactone), MOD-ST/PCL (50% modified starch and 50% polycaprolactone blend) and NONMOD-ST/PCL (50% nonmodified starch and 50% polycaprolactone blends)—were prepared, and their thermal, mechanical, and morphologic properties were investigated to show the increased performance of PCL with the addition of starch and also the effect of modification. It was observed that with the addition of starch the Young's modulus of polycaprolactone was increased and became less ductile, whereas tensile strength and elongation at break values decreased. Biodegradation of these films was inspected under different aerobic environments with the presence of Pseudomonas putida, activated sludge, and compost. It was observed that whereas P. putida had almost no effect on degradation during 90 days, with the presence of activated sludge, considerable deformation of films was observed even in the first 7 days of degradation. In a compost environment, degradation was even faster, and all polymer films were broken into pieces within first 7 days of degradation and no film remained after 15 days.  相似文献   

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