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131.
基于生命周期理论,采用CNI环境影响评价方法对我国水泥生产的环境负荷进行了定量分析。结果表明:水泥生产的环境影响主要体现在温室效应、不可再生能源消耗和不可再生资源消耗,其环境负荷分别占对应环境影响类型世界总负荷的2.76%,2.34%和1.39%,2006年我国水泥生产的环境负荷约占世界总负荷的1.28%,其中,立窑生产工艺、湿法回转窑生产工艺和新型干法生产工艺的环境负荷分别为0.84%,0.12%和0.32%。通过行业结构调整,用新型干法生产工艺取代其他落后的生产工艺,可使我国水泥生产的环境负荷降至世界总负荷的1%左右。 相似文献
132.
畜牧业“碳排放”到“碳足迹”核算方法的研究进展 总被引:1,自引:0,他引:1
全球变暖趋势日益加剧,不仅影响农业可持续发展,而且威胁到人类生存。畜牧业碳排放因其在农业碳排放中乃至全球碳排放中占比较大而日益备受关注。准确核算畜牧业碳排放是制定切实可行的碳减排政策的前提,也为我国在气候变化下承担共同但有差别的减排责任提供话语权。本文基于研究范式的演进,对畜牧业碳排放到碳足迹核算方法的研究发展进行了系统梳理,研究表明,在学者的不断研究与质疑下,畜牧业碳排放到碳足迹的核算方法经历了从OECD核算法、IPCC系数法到生命周期法与投入-产出法的演变与完善,学术界认为区域异质性、养殖规模与管理方式均影响碳足迹;散养比规模化养殖产生更多的碳排放,舍饲比户外放牧排放更多的碳。畜牧业碳足迹核算能够更加全面地反映畜牧业全生命周期的碳排放情况,但由于研究假设、研究方法及研究样本等差异导致不同区域、不同畜产品的碳排放核算结果存在不确定性。运用生命周期法和投入-产出法对欧盟成员国畜牧业碳排放的核算结果基本一致,但运用IPCC系数法和全生命周期法对中国畜牧业碳排放核算中,牛、猪和羊的碳排放量排序结果不尽一致。鉴于核算结果的差异性,本研究对不同核算方法的起源、最早采用时间、特点、局限性等方面进行了归纳总结,并建议后续研究探讨基于生命周期评价的畜牧业碳足迹研究边界的延伸性,标准化畜牧业碳排放或碳足迹核算,避免学者重复核算畜牧业碳排放,以便深入展开畜牧业碳排放其他方面的研究。 相似文献
133.
Ali Tighnavard Balasbaneh Abdul Kadir Bin Marsono 《International Journal of Sustainable Engineering》2017,10(3):176-184
The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO2 emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO2 emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO2 emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO2 emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO2 emissions compared to other schemes. Therefore, S8 has a decreased CO2 effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing. 相似文献
134.
135.
《Journal of environmental science and health. Part. B》2012,47(12):948-953
AbstractOmethoate is an organophosphorus pesticide that poses a major health hazard, especially DNA damage. The purpose of this study was to investigate the factors affecting telomere length in workers exposed to omethoate by analyzing the interaction between cell cycle gene polymorphism and environmental factors. The exposure group consisted of 118 workers exposed to omethoate for 8–10?years, the control group comprised 115 healthy people without occupational toxicant exposure history. The telomere length of genomic DNA from peripheral blood leucocyte was determined with real-time PCR. Polymerase chain reaction and restriction fragment length polymorphism was used to detect the polymorphisms in p53, p21 and MDM2 gene. The telomere length in the (CA?+?AA) genotypes for p21 rs1801270 polymorphism was longer than that in the CC genotype in control group (P?=?0.015). The generalized linear model analysis indicated the interaction of the p21 rs1801270 polymorphic (CA?+?AA) genotypes and smoking has a significant effect on telomere length (β = ?0.258, P?=?0.085). The prolongation of telomere length in omethoate-exposed workers was associated with genotypes (CA?+?AA) of p21 rs1801270, and interactions of (CA?+?AA) genotypes and smoking factor. 相似文献
136.
非均相Fenton-流化床体系主要使用石英砂作为催化剂载体,该技术的实际应用由于催化剂活性寿命低、制备困难等原因而受到限制.提出了一种新型的Fenton-流化床催化剂——负载氧化铁陶粒.使用循环浸泡法制备的负载陶粒对苯甲酸模拟废水的处理效果良好.表征结果分析表明,载体表面铁含量大幅度上升,负载的氧化铁紧紧包裹在陶粒表面,且表面有大量缝隙,利于增加反应比表面积,而密度变化不大.该催化剂的催化活性重复性良好,重复使用4次后对苯甲酸模拟废水依然有较好的处理效果.使用该催化剂进行垃圾渗滤液的降解实验能在一定程度上减少亚铁的投加量,具有较好的实际应用前景. 相似文献
137.
Life cycle assessment of waste paper management: The importance of technology data and system boundaries in assessing recycling and incineration 总被引:2,自引:0,他引:2
Hanna Merrild Anders Damgaard Thomas H. Christensen 《Resources, Conservation and Recycling》2008,52(12):1391-1398
The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing on global warming potentials. The consequence of choosing a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate was studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved biomass, in order to study the importance of the system boundary choices. For recycling, the choice of virgin paper manufacturing data is most important, but the results show that also the impacts from the reprocessing technologies fluctuate greatly. For the overall results the choice of the technology data is of importance when comparing recycling including virgin paper substitution with incineration including energy substitution. Combining an environmentally high or low performing recycling technology with an environmentally high or low performing incineration technology can give quite different results. The modelling showed that recycling of paper, from a life cycle point of view, is environmentally equal or better than incineration with energy recovery only when the recycling technology is at a high environmental performance level. However, the modelling also showed that expanding the system to include substitution of fossil fuel energy by production of energy from the saved biomass associated with recycling will give a completely different result. In this case recycling is always more beneficial than incineration, thus increased recycling is desirable. Expanding the system to include forestry was shown to have a minor effect on the results. As assessments are often performed with a set choice of data and a set recycling rate, it is questionable how useful the results from this kind of LCA are for a policy maker. The high significance of the system boundary choices stresses the importance of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials. 相似文献
138.
Separate collection of municipal solid waste has overcome the 50% threshold in the Asti District in northern Italy, nearly one-third being composed of household and green organic waste. In order to address present and future solutions, it becomes therefore fundamental to assess the environmental performances of the current management of organic waste from separate collection. A from-gate-to-cradle life cycle assessment (LCA) model has been developed by expanding system boundaries, in order to carry out the assessment in the context of the whole waste management streamline. The environmental performances of an existing aerobic plant were made available, based on field measured data, by paying attention to the role and contribution of waste management subsystems. The need for actual and reliable data on materials and energy input, as well as gross and net gains from materials recovery, including benefits arising from use of compost in farming activities, was probably the major drawback that had to be faced. The study integrated the findings of different investigations from the literature with field measured data in order to obtain a more comprehensive framework representative of the area under study. The results may help public administrators to better understand the suitability of using LCA tools when dealing with solid waste management strategies. 相似文献
139.
We used Life Cycle Assessment to scenario model the potential reductions in cumulative energy demand (both fossil and renewable)
and global warming, acidifying, and ozone-depleting emissions associated with a hypothetical national transition from conventional
to organic production of four major field crops [canola (Brassica rapa), corn (Zea mays), soy (Glycine max), and wheat (Triticum aestivum)] in Canada. Models of these systems were constructed using a combination of census data, published values, and the requirements
for organic production described in the Canadian National Organic Standards in order to be broadly representative of the similarities
and differences that characterize these disparate production technologies. Our results indicate that organic crop production
would consume, on average, 39% as much energy and generate 77% of the global warming emissions, 17% of the ozone-depleting
emissions, and 96% of the acidifying emissions associated with current national production of these crops. These differences
were almost exclusively due to the differences in fertilizers used in conventional and organic farming and were most strongly
influenced by the higher cumulative energy demand and emissions associated with producing conventional nitrogen fertilizers
compared to the green manure production used for biological nitrogen fixation in organic agriculture. Overall, we estimate
that a total transition to organic production of these crops in Canada would reduce national energy consumption by 0.8%, global
warming emissions by 0.6%, and acidifying emissions by 1.0% but have a negligible influence on reducing ozone-depleting emissions. 相似文献
140.
Thousands of mammals are killed annually from vehicle collisions, making the issue an important one for conservation biologists
and environmental managers. We recorded all readily identifiable kills on or immediately adjacent to roads in the southern
Great Plains from March 2004–March 2007. We also recorded distance traveled, whether a road was paved or divided, the number
of lanes, and prevailing habitat. Surveys were opportunistic and were conducted by car during conditions of good visibility.
Over our 239 surveys and >16,500 km traveled, we recorded 1412 roadkills from 18 different mammal species (size ranged from
Sciurus squirrels to the white-tailed deer, Odocolieus virginianus). The overall kill rate was 8.50 / 100 km. Four species were prone to collisions: the Virginia opossum (Didelphis virginiana), nine-banded armadillo (Dasypus novemcinctus), striped skunk (Mephitis mephitis), and northern raccoon (Procyon lotor). Together they accounted for approximately 85% (1198) of all roadkills. Mortality rate differed significantly between 2-
and 4-lane roads (8.39 versus 7.79 / 100 km). Kill rates were significantly higher on paved versus unpaved roads (8.60 versus
3.65 / 100 km), but did not depend on whether a road was divided. Roadkills were higher in spring than in fall (1.5×), winter
(1.4×), or summer (1.3×). The spring peak (in kills / 100 km) was driven chiefly by the armadillo (2.76 in spring/summer versus
0.73 in autumn/winter) and opossum (2.65 versus 1.47). By contrast, seasonality was dampened by a late winter/early spring
peak in skunk mortalities, for which 41% occurred in the 6-week period of mid-February through March. The raccoon did not
exhibit a strong seasonal pattern. Our data are consistent with dispersal patterns of these species. Our results underscore
the high rate of highway mortality in the southern plains, as well as differences in seasonality and road type that contribute
to mortality. Conservation and management efforts should focus on creating underpasses or using other means to reduce roadkill
rates. 相似文献