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941.
942.
为获得新疆矿区当前生产规模对应的瓦斯排放基量,调查了研究矿区生产矿井的瓦斯排放现状.根据各矿区2004-2006年生产矿井的开采煤层、生产水平、生产规模和瓦斯排放等参数,对不同矿区和煤田进行了统计分析,计算了新疆矿区当前生产规模对应的瓦斯排放总量,同时对重点瓦斯防治矿区和一般瓦斯防治矿区进行了分类.调查结果表明,新疆矿区煤矿平均吨煤相对瓦斯涌出量由2004年的2.82m3/t增加到2006年的3.09 m3/t,呈逐年递增趋势; 新疆矿区2004-2006年的年平均瓦斯(CH4)排放量为1.05×108 m3/a;准南煤田(I)和塔北煤田(VI)的平均绝对瓦斯涌出量分别占全疆绝对瓦斯涌出总量的64.82%和15.19%,为相对瓦斯富集区,也是当前瓦斯防治的重点区域.按照矿区3年平均绝对瓦斯涌出量(大于1.00m3/min)或平均相对瓦斯涌出量(大于5m3/t)将新疆矿区分为重点瓦斯防治矿区和一般瓦斯防治矿区,并提出了瓦斯分类治理的具体建议.应用灰色系统理论,结合调查数据分别求解了新疆矿区原煤产量与绝对瓦斯涌出量的GM[1,1]预测模型.本研究为新疆煤炭资源后续规模开发过程中的相关环境决策和节能减排政策的实施提供了依据. 相似文献
943.
V. L. Finkenstadt C.-K. Liu P. H. Cooke L. S. Liu J. L. Willett 《Journal of Polymers and the Environment》2008,16(1):19-26
Sorbitol and glycerol were used to plasticize sugar beet pulp-poly(lactic acid) green composites. The plasticizer was incorporated
into sugar beet pulp (SBP) at 0%, 10%, 20%, 30% and 40% w/w at low temperature and shear and then compounded with poly(lactic
acid) (PLA) using twin-screw extrusion and injection molding. The SBP:PLA ratio was maintained at 30:70. As expected, tensile
strength decreased by 25% and the elongation increased. Acoustic emission (AE) showed correlated debonding and fracture mechanisms
for up to 20% w/w plasticizer and uncorrelated debonding and fracture for 30–40% sorbitol and 30% glycerol content in SBP–PLA
composites. All samples had a well dispersed SBP phase with some aggregation in the PLA matrix. However, at 40% glycerol plasticized
SBP–PLA composites exhibited unique AE behavior and confocal microscopy revealed the plasticized SBP and PLA formed a co-continuous
two phase system.
相似文献
V. L. FinkenstadtEmail: |
944.
Chun Wai Lee Dennis G. Tabor Kenneth A. Cowen 《Journal of Material Cycles and Waste Management》2008,10(1):38-45
The performance of four dioxin emission monitors, including two long-term sampling devices, the Dioxin-MonitoringSystem (DMS)
and AMESA (the adsorption method for sampling dioxins and furans), and two semireal-time continuous monitors, the resonance
ionization with multimirror photon accumulation time-of-flight mass spectrometer (RIMMPA-TOFMS) and the jet resonance-enhanced
multiphoton ionization (jet-REMPI) system were tested. A package boiler burning a simulated chlorinated hazardous waste was
used for a total of nine tests. Reference samples were collected during each test and analyzed for polychlorinated dibenzodioxins
and dibenzofurans (PCDDs/Fs) using gas chromatography mass spectrometry. The PCDD/F concentrations of the reference samples
measured by EPA Method 23 ranged from 0.9 to 6.0 ng toxic equivalence (TEQ)/dry standard cubic meter. The relative accuracies
achieved by DMS, AMESA, and jet-REMPI varied from 22.6% to 78.2%, with 100% data completeness. The RIMMPA-TOFMS produced no
quantifiable results due to various difficulties associated with the instrument during the testing. The two long-term samplers
were easy to install and operate and provided a cumulative, averaged emission for the sampling period. The operations of the
two semi-real-time continuous monitors were relatively complex, but one of them provided on-site, real-time data for PCDD/F
emissions from measurement of a TEQ correlative indicator compound. This article summarizes results from the individual Environmental
Technology Verification reports for the four dioxin monitors.
This work was presented, in part, at the Fourth International Conference on Combustion, Incineration/Pyrolysis and Emission
Control (i-CIPEC) 相似文献
945.
946.
农业作为国民经济的基础,是生态文明的重要内容,其文明程度直接体现生态文明程度.生态文明建设给农业经营提出了更高的要求,也为农业生产的发展指明了方向.充分认识生态文明建设与农业生产的关系,加强农业相关人员的生态文明教育和农业环保法制建设,实施更加科学、文明的农业经营方式将对促进农业的可持续发展和生态文明建设发挥积极的作用. 相似文献
947.
Paper recycling is an environmental important activity that is carried out in all the countries, but during the recycling process a paper waste is produced. Generally these wastes are placed in landfill sites but it is possible to profit it as secondary fuel and raw material in manufacture furnaces.
In this work the combustion of the waste papers with cement and ceramic raw material has been studied with the objective to analyse the interaction of these substances with the emitted pollutants like PAHs and PCDD/Fs.
The results of the study show that the presence of inorganic material produces an increment in the lighter PAH emission but chlorinated compounds are not affected. The PCDD/F emission level found in the combustion of this waste is quite low compared with other wastes subjected to similar conditions. 相似文献
948.
949.
基于船舶AIS数据的船舶废气排放评估计算模型,以高斯烟团扩散模型为核心,结合船舶航行和排放特征,构建移动船舶源排放烟团扩散模型。利用控制变量法,在其他变量参数相同条件下,分别设定不同风向、不同大气稳定度、不同高程平面,仿真模拟航行状态下的船舶排放烟团扩散至空间环境中的质量浓度分布情况,分析船舶在不同环境参数下的扩散特征。结果表明,仿真模拟结果与实际气体空间质量浓度分布情况相符。通过在深圳市盐田港区布设船舶废气排放岸基固定嗅探监测设备,对港区进、离港和过往船舶进行大气污染物排放组分(SO2、CO2、NO、NO2)全天在线实时监测,以SO2作为试验样本气体,船舶排放的SO2排放至监测站的模拟质量浓度与实际监测质量浓度标准误差为19.81%,在合理的误差范围内,验证了船舶废气排放扩散模拟计算方法的科学有效性。 相似文献
950.
I. A. Romanenko V. A. Romanenkov P. Smith J. U. Smith O. D. Sirotenko N. V. Lisovoi L. K. Shevtsova D. I. Rukhovich P. V. Koroleva 《Regional Environmental Change》2007,7(2):63-77
This study estimates the consequences of climate change on cropland with and without implementation of adaptation measures,
paying special attention to the maintenance of soil organic carbon (C) stocks. We examine the possibility for regional sustainable
agricultural management practice that combines both maintenance and gain in soil carbon level with profit maximization. Future
scenarios of Regional Agricultural Production Systems (RAPS) were constructed for 2000–2070 based on linking the effects of
global climate change, predicted change in productivity parameters for the main agricultural crops, land-use and soil database
parameters. The RAPS were used to examine profitability and feasibility of alternative agricultural scenarios, based on an
economic model. A number of recommendations for decision making were proposed based on an assessment of the efficiency of
adaptation in animal husbandry and in the crop production sector, after analysis of current percentage of perennial grass
in rotation in comparison with future economic scenarios.
Figures in color are available at 相似文献