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381.
Ni/Fe双金属降解四氯化碳和四氯乙烯的对比试验 总被引:3,自引:0,他引:3
以四氯化碳(CT)和四氯乙烯(PCE)为目标污染物,以批试验方法研究Ni/Fe双金属对CT和PCE的还原性脱氯.结果表明:Ni/Fe双金属可有效去除水中的CT和PCE;Ni/Fe双金属对CT和PCE的降解反应均符合准一级反应动力学方程;在相似的反应条件下,Ni/Fe双金属对CT和PCE脱氯的反应速率常数(kobs)之比为1.48和1.67,说明Ni/Fe双金属对CT的脱氯速率要快于对PCE的脱氯速率;Ni/Fe双金属可对PCE完全脱氯,但对CT脱氯过程中产生少量三氯甲烷(TCM). 相似文献
382.
二氧化碳捕获和存储作为清洁发展机制项目的潜力与障碍分析 总被引:1,自引:0,他引:1
本文目的在于讨论和分析二氧化碳捕获和储存技术项目(CCS)作为清洁发展机制(CDM)项目的障碍和机遇。CCS被视为减少CO2人为排放量的选择方案之一,但在发展中国家,该技术面临着政策、成本和技术上的挑战。对这些国家而言,CDM几乎是发展CCS的唯一动机。本文分析了CCS作为CDM项目面临的项目边界、持久性、渗漏和可持续发展性的问题,并展望了未来的发展趋势。 相似文献
383.
The sol–gel method was used to synthesize a series of metal oxides-supported activated carbon fiber (ACF) and the simultaneous catalytic hydrolysis activity of carbonyl sulfide (COS)and carbon disulfide (CS2) at relatively low temperatures of 60°C was tested.The effects of preparation conditions on the catalyst properties were investigated,including the kinds and amount of metal oxides and calcination temperatures.The activity tests indicated that catalysts with 5 wt.%Ni after calcini... 相似文献
384.
Adsorptive efficacy of lignocellulosic waste char (LW-CHAR) and activated carbon (LW-AC) toward inorganic (Hg2+) and organic (MeHg+) mercury ions was studied. The LW-CHAR and LW-AC were, respectively, prepared by carbonization and KOH activation processes of lignocellulosic waste (LW) carried out at 700 °C. The Hg2+ adsorption onto the LW-CHAR was lower than LW-AC, however, an opposite result was observed for the MeHg+ indicating the nature of the surface interactions of both mercury ions to respective adsorbent surfaces was significantly different. The adsorption data analysis of both mercury ions was found however to only follow the Langmuir isotherm and pseudo-second order kinetic models whereby a combination of chemisorption and diffusional process was the governing mercury ions adsorption mechanism. 相似文献
385.
We study optimal carbon capture and storage (CCS) from point sources, taking into account damages incurred from the accumulation of carbon in the atmosphere and exhaustibility of fossil fuel reserves. High carbon concentrations call for full CCS, meaning zero net emissions. We identify conditions under which partial or no CCS is optimal. In the absence of CCS the CO2 stock might be inverted U-shaped. With CCS more complicated behavior may arise. It can be optimal to have full capture initially, yielding a decreasing stock, then partial capture while keeping the CO2 stock constant, and a final phase without capture but with an inverted U-shaped CO2 stock. We also introduce the option of adaptation and provide a unified theory regarding the optimal use of CCS and adaptation. 相似文献
386.
387.
炭黑工业尾气净化及余热利用 总被引:1,自引:0,他引:1
研究表明,炭黑工业生产过程尾气中的可燃气态污染物CO、H2、及CH4等,采用直接燃烧法,是目前我国炭黑尾气净化和回收利用的最佳控制方法。直接燃烧法,不仅可将尾气中可燃气态污染物转变为CO2和H2O,且可回收利用其热量,余热利用率可提高40%以上。经济技术评价表明,采用直接燃烧法和炭黑尾气发电,其经济效益和环境效益十分可观。 相似文献
388.
M. A. Castillo-Santiago A. Hellier R. Tipper B. H. J. de Jong 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1213-1235
This study examines the correlation between deforestation, carbon dioxide emissions and potential causal factors of land-use
change within an area of 2.7 million ha in Chiapas, southern Mexico between 1975 and 1996. Digitized land-use maps and interpreted
satellite images were used to quantify land-use changes. Geo-referenced databases of population and digitized maps of roads
and topography were used to determine which factors could be used to explain observed changes in land-use. The study analyzed
the relationship between carbon emissions during this period and two types of possible causal factors: “predisposing” factors
that determine the susceptibility of a particular area of forest to change (slope, distance to agriculture and roads, land
tenure) and “driving” factors representing the pressures for change (population density, poverty). The correlated factors
were combined in risk matrices, which show the proportion of vulnerable carbon stocks lost in areas with defined social, economic
and environmental characteristics. Such matrices could be used to predict future deforestation rates and provide a verifiable
evidence-base for defining baseline carbon emissions for forest conservation projects. Based on the results of the analysis,
two matrices were constructed, using population density as the single most important driving factor and distance from roads
and distance from agriculture as the two alternatives for the predisposing factors of deforestation. 相似文献
389.
Jaroslav Hynt Miloslav imek Petr Br
ek Sren O. Petersen 《Agriculture, ecosystems & environment》2007,120(2-4):269-279
Cattle overwintering areas common in central Europe may represent significant point sources of the important greenhouse gases, nitrous oxide (N2O) and carbon dioxide (CO2). A 2-year field study was carried out in order to estimate the emissions of N2O and CO2 from soil in a cattle overwintering area located in the southwest of the Czech Republic. The measurements were performed at three sampling locations along a gradient of animal impact (severe, moderate, slight) to test the hypothesis that emissions of CO2 and N2O are positively related to the degree of impact. In addition to CO2 and N2O fluxes determined by using non-vented manual closed chambers, soil mineral nitrogen (NH4+ and NO3−), pH and temperature were determined to assess their regulatory role and impact on gas fluxes. The overwintering area was about 4 ha and it had been used for overwintering of about 90 cows since 1995. Deposition of animal excreta resulted in a significant accumulation of nitrogen in the soil during winter, but most of the N2O was emitted during a few short periods in spring and/or in late autumn. Maximum N2O fluxes of up to 2.5 mg N2O-N m−2 h−1 were recorded at the most impacted location near the animal house, where the highest concentrations of soil mineral nitrogen also occurred. The emissions of CO2 showed a completely different pattern to those of N2O, being correlated with soil temperature; the highest emissions thus occurred in June–July, while very low fluxes were found in winter. Emission values ranged from about 0 to 700 mg C-CO2 m−2 h−1. Furthermore, the effect of animal impact on CO2 emissions was opposite to that on N2O fluxes, as the highest CO2 fluxes were mostly recorded at the least impacted location, where respiration of plants most likely increased overall CO2 production. The results show that cattle overwintering areas are important sources of greenhouse gases, including N2O and CO2. Fluxes of these two gases are, however, differently distributed over the year, which also suggests that they are controlled by different environmental and soil factors. 相似文献
390.
活性炭纤维处理含多氯联苯废水的研究 总被引:19,自引:0,他引:19
对活性炭纤维吸附处理含多氯联苯废水进行了研究,确定了相关条件下的吸附容量,并实际应用于含多氯联苯废水的处理中。 相似文献