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61.
This paper presents an experimental study on employing a pellet form of catalyst in photo-reduction of carbon dioxide with water. Water was first absorbed into titania pellets. Highly purified carbon dioxide gas was then discharged into a reactor containing the wet pellets, which were then illuminated continuously for 65 hours using UVC lamps. Analysing the products accumulated in the reactor confirmed that methane and hydrogen were produced through photo-reduction of carbon dioxide with water. No other hydrocarbons were detected. Increasing the temperature in the reactor has showed little change on the amount of methane produced.  相似文献   
62.
“限塑令”政策有效性评估的实例分析   总被引:2,自引:0,他引:2  
通过对上海市杨浦区3个居民小区"限塑令"实施前后塑料袋消费情况的调研.发现"限塑令"在一定程度上起到了塑料袋减量化的作用,但效果并不明显.其瓶颈在于我国当前对商品流通领域的控制能力非常薄弱,对非正规零售商约束力度不够、监管缺位,导致他们无视"限塑令"的规定,继续提供免费塑料袋,从而严重架空了"限塑令"的减量化效果.文章中提出了通过加强监管和处罚力度、培育社会参与机制,以及加大公众宣传活动等措施,消除"限塑令"的政策死角,以真正实现塑料购物袋消费减量化的目标.  相似文献   
63.
通过对自来水厂、净化厂及两厂混合后的泥水的研究,来分析两厂泥水的匹配性。实验表明:自来水厂泥水排入净化厂与其泥水一起处理,能够促进净化厂泥水的浓缩,降低浓缩后污泥的比阻,而且在一定范围内能够降低污泥的最终体积,达到减量化的目的。  相似文献   
64.
通过采用调查与统计年鉴数据相结合的方法,计算出辽宁省电力行业CO2排放量,结果表明,辽宁省电力行业的CO2排放量为1.52亿t,占辽宁省CO2总排放量的43.80%。其中,大连电力行业的CO2排放量居辽宁省电力行业第1位,铁岭、抚顺和葫芦岛分别排在2、3、4位。并提出削减辽宁省电力行业CO2排放量的措施  相似文献   
65.
基于沈抚灌渠(抚顺段)高污染、高排放的特点,设计了一套生态环保型污染减排对策,在沈抚灌渠东部起点处建设东洲再生水厂及传输污水管线工程;在中西部建海城污水处理厂及污水截流工程;在西部的抚顺开发区段采用生态修复技术对出市前的污水进行综合整治和处理,采取治污、清淤、引水和两岸景观建设四项措施,使沈抚灌渠水质达到地表水Ⅳ标准.  相似文献   
66.
畜禽养殖污水污染治理现状及发展趋势   总被引:3,自引:0,他引:3  
畜禽养殖过程中产生的大量污水是目前养殖污染治理的一大难题。针对目前畜禽养殖污水治理过程中存在的管理力度不够、技术可行性差、运行成本过高等问题,提出了今后畜禽养殖污水治理的方向,应以"循环经济"为核心,以污染排放最小化和资源利用最大化为原则,实现经济效益和环境效益的和谐统一。  相似文献   
67.
A novel Ultrasonic Assisted Membrane Reduction (UAMR)-hydrothermal method was used to prepare flower-like Pt/CeO2 catalysts. The texture, physical/chemical properties, and reducibility of the flower-like Pt/CeO2 catalysts were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), N2 adsorption, and hydrogen temperature programmed reduction (HE-TPR) techniques. The catalytic performance of the catalysts for treating automobile emission was studied relative to samples prepared by the conventional wetness impregnation method. The Pt/CeO2 catalysts fabricated by this novel method showed high specific surface area and metal dispersion, excellent three-way catalytic activity, and good thermal stability. The strong interaction between the Pt nanoparticles and CeO2 improved the thermal stability. The Ce4+ ions were incorporated into the surfactant chains and the Pt nanoparticles were stabilized through an exchange reaction of the surface hydroxyl groups. The SEM results demonstrated that the Pt/CeO2 catalysts had a typical three-dimensional (3D) hierarchical porous struc- ture, which was favorable for surface reaction and enhanced the exposure degree of the Pt nanoparticles. In brief, the flower-like Pt/CeO2 catalysts prepared by UAMR-hydrothermal method exhibited a higher Pt metal dispersion, smaller particle size, better three-way catalytic activity, and improved thermal stability versus conven- tional materials.  相似文献   
68.
The voluntary emission reduction (VER) trading mechanism has played an important role in China’s seven pilot carbon markets. From a comprehensive review of the VER trading and offsetting mechanisms since 2013, this study analyses the quality management of the Chinese Certified Emission Reduction (CCER) in the pilot carbon markets, conducts a comparative analysis of the geographical and field distributions of proposed and registered projects and emission reductions and provides the CCER supply outlook for 2020 in the aspects of on record, project registration, emission reduction registration and emission reduction issuance. Results show that the potential number of CCER projects by 2020 will be 2,864, 1,047, 818, and 286 with the corresponding emission reductions amounting to 493, 212, 133, and 49 million tCO2e, respectively. Although considerable progress has been made, China remains confronted with many challenges in developing the VER trading system. Accordingly, policy stability and continuity and guarding against market risks should be maintained to enable the system to play a substantial role in promoting ecological progress and green low-carbon development in China.  相似文献   
69.
生命周期评价在中国城市垃圾减量化的应用   总被引:9,自引:0,他引:9       下载免费PDF全文
为减少城市垃圾,介绍了生命周期评价方法,并将其引入城市垃圾管理系统,建立了适合我国国情的城市垃圾生命周期评价框架。生命周期评价框架的建立有助于改进城市垃圾管理,是减少城市垃圾产生的有用工具。   相似文献   
70.
我国总磷排放标准日趋严格,污水处理厂为保证出水总磷达标,过量投加化学除磷剂,造成资源浪费.为在出水水质达标的基础上节省化学除磷剂添加量,以山东某污水处理厂为例设计了化学除磷精确控制系统.在充分考虑仪器故障潜在风险的前提下,根据进水磷酸盐负荷实时调整药剂投加量,采用"前馈+反馈"控制的模式,实现加药过程的自动化及智能化....  相似文献   
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