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91.
漆文光  陆少鸣 《四川环境》2006,25(3):18-21,49
本文通过分析饮用水深度处理中试工艺各处理单元出水水质指标的变化研究臭氧在臭氧生物活性炭工艺中的作用。试验结果表明:在中试工艺中,臭氧具有很好的氧化、杀藻和消毒的作用;并且两级臭氧氧化分别对常规处理单元和颗粒活性炭去除污染物具有一定的促进作用。  相似文献   
92.
以黄浦江水源水厂的滤后水为试验对象,进行饮用水O3-BAC深度处理工艺影响因素的中试研完。针对进水水质的试验结果表明,最优臭氧投加量为3mg/L左右,空床停留时间为15min左右。试验结果可为工程设计提供有益的参考。  相似文献   
93.
试验工艺流程的方案选定,充分吸收了各炼油厂进行的污水深度处理的成功试验经验,以原臭氧生物活性炭工艺单元为基础,提出了以混凝气浮与臭氧生物活性炭串联工艺为核心的总体工艺流程,以降低工程投资及处理成本,提高污水回用的经济效益;同时,指出试验过程中所存在的问题及其对策。因此,开展炼油污水深度处理回用工艺试验研究,必将为炼油污水深度处理提供强有力的技术支撑,可作为相关污水回用处理工艺选择的参考。  相似文献   
94.
炭法烟气脱硫技术研究进展   总被引:4,自引:1,他引:4  
炭法烟气脱硫技术经半个多世纪的发展,在脱硫剂、脱硫工艺、脱硫原理及联合脱除氮氧化物和有毒物质等方面取得了许多进展。在概述炭法烟气脱硫技术研究进展的同时,分析了制约炭法烟气脱硫技术发展的原因并对炭法烟气脱硫技术的发展方向提出了几点建议。  相似文献   
95.
ZnCl2-微波法制甘蔗渣活性炭工艺条件研究   总被引:6,自引:0,他引:6  
以工业副产物甘蔗渣为原料,ZnCl2-微波法制备活性炭,用正交实验研究了活化剂ZnCl2浸泡浓度、浸泡时间、微波功率和作用时间等实验因素对活性炭性能的影响.  相似文献   
96.
采用改性活性炭粉末对用纯净水加氟化钠配制而成的含氟水溶液进行动态电吸附去除实验.研究不同电压、电吸附时间,以及Cl-和SO2-4对氟离子去除的影响,并探讨吸附动力学和吸附方程.实验结果表明:活性炭对氟离子的吸附等温方程符合Freundlich方程,吸附动力学符合一级动力学方程;活性炭对氟离子去除与所施加的电位、吸附时间等因素有关,施加的电位越大,去除效果越好;随着吸附去除时间的延长,氟离子浓度下降趋缓;Cl-对氟离子去除影响很小,而SO2-4对氟离子去除有显著的不利影响.  相似文献   
97.
Loss of grassland species resulting from activities such as off-road vehicle use increases the need for models that predict effects of anthropogenic disturbance. The relationship of disturbance by military training to plant species richness and composition on two soils (Foard and Lawton) in a mixed prairie area was investigated. Track cover (cover of vehicle disturbance to the soil) and soil organic carbon were selected as measures of short- and long-term disturbance, respectively. Soil and vegetation data, collected in 1-m2 quadrats, were analyzed at three spatial scales (60, 10, and 1 m2). Plant species richness peaked at intermediate levels of soil organic carbon at the 10-m2 and 1-m2 spatial scales on both the Lawton and Foard soils, and at intermediate levels of track cover at all three spatial scales on the Foard soil. Species composition differed across the disturbance gradient on the Foard soil but not on the Lawton soil. Disturbance increased total plant species richness on the Foard soil. The authors conclude that disturbance up to intermediate levels can be used to maintain biodiversity by enriching the plant species pool.  相似文献   
98.
Asymmetric regulation of a global pollutant between countries can alter the competitiveness of industries and lead to emissions leakage, which hampers countries’ welfare. In order to limit leakage, governments consider supporting domestic trade-exposed firms by subsidizing their investments in abatement technology. The suppliers of such technologies tend to be less than perfectly competitive, particularly when both emissions regulations and advanced technologies are new. In this context of twin market failures, we consider the relative effects and desirability of subsidies for abatement technology. We find a more robust recommendation for upstream subsidies than for downstream subsidies. Downstream subsidies tend to increase global abatement technology prices, reduce pollution abatement abroad and increase emission leakage. On the contrary, upstream subsidies reduce abatement technology prices, and hence also emissions leakage.  相似文献   
99.
Upcycling polymer wastes into useful, and valuable carbon based materials, is a challenging process. We report a novel catalyst-free and solvent-free technique for the formation of nano channeled ultrafine carbon tubes (NCUFCTs) and multiwalled carbon nanotubes (MWCNTs) from polyethylene terephthalate (PET) wastes, using rotating cathode arc discharge technique. The soot obtain from the anode contains ultrafine and nano-sized solid carbon spheres (SCS) with a mean diameter of 221 nm and 100 nm, respectively, formed at the lower temperature region of the anode where the temperature is approximately 1700 °C. The carbon spheres are converted into long “Y” type branched and non-branched NCUFCTs and MWCNTs at higher temperature regions where the temperature is approximately 2600 °C, with mean diameters of 364 nm and 95 nm, respectively. Soot deposited on the cathode is composed of MWCNTs with a mean diameter of 20 nm and other nanoparticles. The tubular structures present in the anode are longer, bent and often coiled with lesser graphitization compared to the nanotubes in the soot on the cathode.  相似文献   
100.
Large, intact areas of tropical peatland are highly threatened at a global scale by the expansion of commercial agriculture and other forms of economic development. Conserving peatlands on a landscape scale, with their hydrology intact, is of international conservation importance to preserve their distinctive biodiversity and ecosystem services and maintain their resilience to future environmental change. We explored threats to and opportunities for conserving remaining intact tropical peatlands; thus, we excluded peatlands of Indonesia and Malaysia, where extensive deforestation, drainage, and conversion to plantations means conservation in this region can protect only small fragments of the original ecosystem. We focused on a case study, the Pastaza‐Marañón Foreland Basin (PMFB) in Peru, which is among the largest known intact tropical peatland landscapes in the world and is representative of peatland vulnerability. Maintenance of the hydrological conditions critical for carbon storage and ecosystem function of peatlands is, in the PMFB, primarily threatened by expansion of commercial agriculture linked to new transport infrastructure that is facilitating access to remote areas. There remain opportunities in the PMFB and elsewhere to develop alternative, more sustainable land‐use practices. Although some of the peatlands in the PMFB fall within existing legally protected areas, this protection does not include the most carbon‐dense (domed pole forest) areas. New carbon‐based conservation instruments (e.g., REDD+, Green Climate Fund), developing markets for sustainable peatland products, transferring land title to local communities, and expanding protected areas offer pathways to increased protection for intact tropical peatlands in Amazonia and elsewhere, such as those in New Guinea and Central Africa which remain, for the moment, broadly beyond the frontier of commercial development.  相似文献   
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