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891.
根据污染源现场调研结果,结合现有污染控制工艺所能达到的技术水平,建议污水排放标准中As浓度由现国家排放标准的0 5mg/L调整为0 1mg/L;Pb不变为1 0mg/L。大气污染物排放标准中As和Pb不变为1 0mg/L。大气污染物排放标准As和Pb的浓度限值分别是为0 5mg/m3和0 7mg/m3。 相似文献
892.
Will Simplified Modalities and Procedures Make More Small-Scale Forestry Projects Viable Under the Clean Development Mechanism? 总被引:2,自引:0,他引:2
Bruno Locatelli Lucio Pedroni 《Mitigation and Adaptation Strategies for Global Change》2006,11(3):621-643
Simplified modalities and procedures (M&P) are expected to increase the viability of small-scale project activities under
the Clean Development Mechanism (CDM). A small-scale afforestation or reforestation (AR) project is defined as a project removing
less than 8 kilotons of carbon dioxide equivalent (CO2e) per year. Depending on the project type and the method for measuring scale, 8 kilotons of CO2e per year correspond to highly diverse areas, possibly ranging from 200 to 6000 ha. Using a model to calculate the minimum
project scale above which the CDM is a positive financial incentive for eligible AR project activities, the paper analyzes
whether a reduction of transaction costs under simplified M&P will be a sufficient incentive to motivate small-scale participation
in the CDM. Model results show that, even under optimistic assumptions on carbon market conditions and transaction costs,
small-scale project activities will not benefit from simplified M&P. Results also show that project activities removing more
than 8 kilotons of CO2e per year and registered as small-scale would be the ones that could benefit the most from simplified M&P. It is concluded
that the participation of small-scale project activities to the CDM requires more than simplified M&P, the price of expiring
Certified Emission Reductions being one of the most critical parameters. 相似文献
893.
颗粒活性炭对UASB处理垃圾渗滤液促进作用的研究 总被引:1,自引:0,他引:1
通过对比研究,考查了用UASB处理垃圾渗滤液时,投加颗粒活性炭对加速UASB反应器中污泥颗粒化进程、缩短启动时间、提高处理效果的影响。结果显示:启动时间缩短了近1/3,最大有机负荷提高近40%且出现了更大颗粒污泥,但COD去除效率没有明显提高。 相似文献
894.
Black carbon (BC) in surface sediments from Henan section of Yellow River and Huaihe River, China, was determined. Average content of BC in Huaihe River was 0.33%, higher than that in Yellow River (n?=?23) with mean value of 0.15%. Distribution patterns of BC in Yellow River and Huaihe River were similar, namely that tributaries had higher BC content than main stream. In addition, BC content in the mainstream of Yellow River and Huaihe River decreased with altitude. The BC content presented a significant positive correlation with clay (r?=?0.672; p?<?0.01) content in Yellow River, while neither did in Huaihe River. The ratio of BC/TOC ranged from 1.8–57.4% (median 29.6%), evidencing pyrogenic fossil fuel source of BC in Yellow River. Relatively low values of BC/TOC in Huaihe River (5.3%–28.8%, median 7.5%,) reflected that the origin of BC is from burning of biomass. In addition, Pearson rank correlation analysis showed that BC was in strong correlation with lighter PAH in Yellow River, while BC was in significant correlation with heavier PAH in Huaihe River. The ratio of BC/TOC indicated that BC in Yellow River mainly came from fossil fuel combustion, while BC in Huaihe River was primarily from biomass burning. 相似文献
895.
896.
Chuang CL Chiang PC Chang EE 《Environmental science and pollution research international》2003,10(1):6-8
An activated carbon bed adsorption process is influenced by the adsorbents' characteristics, volatile organic compound (VOC) characteristics, and process conditions. In the literatures, the adsorption processes of the adsorbents and VOCs were usually considered to be in equilibrium. In this study, the VOC adsorption processes by activated carbon were considered to be a kinetic process, i.e. they are not in equilibrium. Then, isothermal adsorption curves and a small column experiment were simulated. 相似文献
897.
898.
Edward Heyse Dongping Dai P. Suresh C. Rao Joseph J. Delfino 《Journal of contaminant hydrology》1997,25(3-4)
This paper introduces a new reversible-flow design for a continuously stirred reactor used to study sorption mass transfer in soil and solvent systems. The stirred reactor has potential advantages over conventional packed column or batch reactors because it isolates intraparticle sorption rate limitations from advective-dispersive transport, yet allows changes to flux through the reactor for analysis of sorption kinetics under dynamic conditions. Previously, stirred reactors have often failed due to clogging of sediment on the effluent frit. The reverse-flow backwashing design allows longer life and higher confidence in maintaining mixed conditions than previous designs. Mass transfer 'rate coefficients estimated from stirred and column experiments are compared; both techniques produced results consistent with a published correlation. The data also show that fitted sorption mass transfer coefficients can be strongly dependent on the choice of equilibrium partition coefficient (i.e. batch or first-moment derived values), and that the conventional two-site sorption kinetics model fails to accurately predict sorption mass transfer in the presence of changing solvent velocity through the reactor. 相似文献
899.
可交易排污许可证在传统的排污许可证基础上,引入市场机制。不但对企业选择污染控制手段赋予更大的灵活性,而且可以大大节约水污染控制费用、剌激企业开发并建设更加经济有效的污染控制技术。国外十多年的研究和实践证明可交易排污许可证是一种经济而有效的环境管理手段。水污染排放许可证制度在我国的应用已有一定基础。在条件具备的地区可以引进可交易水污染物排放许可证制度,本文回顾了“可交易水污染许可证制度”的理论分析和国外实践,进而探讨在中国的应用前景 相似文献
900.
稀土金属具有一些特殊的性能,这使得其对碳质材料还原NO的反应可能表现出特殊的催化效果,而此方面的研究没有报道.为了研究稀土金属对活性炭还原NO反应的催化效果,采用浸渍法制备了负载氧化镧的活性炭颗粒(La/C),并在无氧的固定床反应器中进行了程序升温反应和等温反应,考察了气体流量、NO的入口浓度、反应温度和氧化镧负载量对反应活性的影响,同时对反应机理和动力学进行了初步探讨.研究结果表明负载氧化镧的活性炭还原NO的反应是一级反应.由于炭表面3%(质量分数)的氧化镧的存在,C-NO反应的起始反应温度从500 ℃降低到300 ℃,反应活性大大提高,反应活化能从88.95 kJ/mol降低到51.05 kJ/mol.氧化镧的负载量对反应活性有重要影响,但负载量的大量增加对反应活性的提高效果甚微,最佳负载量为1.5%.La/C体系在反应中较稳定,而反应温度的升高对其稳定性不利. 相似文献