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811.
溶剂萃取法提取废旧碱性电池中的有价成分   总被引:8,自引:1,他引:8  
黄莺  秦炜  戴猷元 《化工环保》2002,22(4):221-224
为回收利用废旧电池,进行了溶剂萃取法提取碱性废弃电池中锌、锰金属的试验研究。选择南孚(AA)碱性废电池为处理样品,通过粉碎、水浸、酸浸等步骤,获得含锌、锰离子的稀溶液,并利用模拟体系得到的萃取结果进行浸出液的萃取性能试验研究。结果表明,每个废电池填充物中含锌和锰分别为0.25g和0.36g,具有可观的回收价值;采用完全皂化的二(2-乙基己基)磷酸(D2EHPA)/煤油为萃取剂提取含锌锰的酸浸出液,一级萃取就可获得60%以上的提取率。  相似文献   
812.
构建生态云南的基本要素有:明确的责任;心理准备充分;资金充裕;社会动员、组织动员高效便捷;打环境官司容易;完善的约束——激励机制;履行生态伦理的能力。生态补偿能创造和积累构建生态云南所需要素和条件。本文将云南生态补偿划分为伦理型生态补偿和法制型生态补偿,探讨各类生态补偿的发展策略、步骤、方式和手段。  相似文献   
813.
China’s new Classification-Based Forest Management (CFM) is a two-class system, including Commodity Forest (CoF) and Ecological Welfare Forest (EWF) lands, so named according to differences in their distinct functions and services. The purposes of CFM are to improve forestry economic systems, strengthen resource management in a market economy, ease the conflicts between wood demands and public welfare, and meet the diversified needs for forest services in China. The formative process of China’s CFM has involved a series of trials and revisions. China’s central government accelerated the reform of CFM in the year 2000 and completed the final version in 2003. CFM was implemented at the provincial level with the aid of subsidies from the central government. About a quarter of the forestland in China was approved as National EWF lands by the State Forestry Administration in 2006 and 2007. Logging is prohibited on National EWF lands, and their landowners or managers receive subsidies of about 70 RMB (US$10) per hectare from the central government. CFM represents a new forestry strategy in China and its implementation inevitably faces challenges in promoting the understanding of forest ecological services, generalizing nationwide criteria for identifying EWF and CoF lands, setting up forest-specific compensation mechanisms for ecological benefits, enhancing the knowledge of administrators and the general public about CFM, and sustaining EWF lands under China’s current forestland tenure system. CFM does, however, offer a viable pathway toward sustainable forest management in China.  相似文献   
814.
Based on a modified Leenheer DOM fractionation scheme, fractionation of DOM from the paddy soil was conducted by using XAD-8 resin into hydrophobic bases ( HOB), hydrophobic acids ( HOA), acid-insoluble matter ( AIM), hydrophobic neutrals ( HON ) and hydrophilic matter(HIM). In total carbon content of DOM, 35.32% were the HIM and only 0.73% the HOB. However, HOA and AIM altogether occupied 53.45%, while the HON fraction represented 10%. The sorption experiments were conducted to determine the sorption capacity of pyrene on unfractionated DOM and its fractions. Elemental analysis, ^1H-NMR and FTIR spectra were carried out on unfractionated DOM and its fractions to examine the relationship between the structure of DOM and partition coefficients( Kac ). The results showed that HON had a greater affinity for binding pyrene than other fractions. While HON was characterized by large long-chain alkylate (aliphatic structure). AIM exhibited relative higher Kac values than HOA and HIM, due to much aromatic structure in AIM, while the high content of carboxylic groups of HOA and HIM depressed their binding capacity. This study demonstrated HON is a key subcomponents of DOM in binding of pyrene, in other words, aliphalic structure in DOM play an important role in binding of pyrene.  相似文献   
815.
氨氧化细菌的富集培养及影响因素的研究   总被引:1,自引:0,他引:1  
采用间歇培养方式,对富集氨氧化细菌的过程进行了研究,并探讨了温度、初始pH值、DO、碱度、进水氨氮浓度对短程硝化作用的影响.实验发现:氨氧化细菌富集完成后,氨氧化速率达到22.8 mg/(L·h),亚硝酸盐积累率在80%左右,氨氧化细菌的数量可提高至富集前的32.6倍.此外,对影响因素的研究发现,当温度30℃、pH=8.5、DO=0.5 mg/L、HCO3-/NH4+-N(摩尔比)=1.67、进水氨氮小于400 mg/L时,有利于实现短程硝化.  相似文献   
816.
ABR-生物接触氧化工艺处理城市生活垃圾渗滤液   总被引:1,自引:0,他引:1  
采用ABR反应器与生物接触氧化法相结合的工艺处理城市生活垃圾渗滤液。运行结果表明:该工艺对COD具有较高的去除率,对水力负荷、容积负荷具有较强的抗冲击能力,在处理垃圾渗滤液方面具有一定的工艺先进性。  相似文献   
817.
原油电脱盐含油废水由于乳化带油严重,破乳分离困难,处理难度大。文章对目前工业化应用技术成熟的旋流油水分离、化学破乳及电化学3种电脱盐含油废水除油工艺,在工艺流程、工业应用现状、应用效果等几方面进行了对比研究。结果表明,电化学除油工艺具有除油率高、效果稳定、费用低、设备简单、抗冲击力强、占地面积小等优势,除油率和COD去除率大于90%,对悬浮物、胶体、重金属等也有一定的去除效果,具有较好的应用前景。  相似文献   
818.
多中心治理下公众参与大气污染防治路径探析   总被引:6,自引:0,他引:6  
动员全社会力量保护环境,积极推动公众参与环保工作,是解决环境保护问题的根本途径。运用多中心治理理论分析,发现政府治污理念陈旧、制度不健全、公众责任意识淡漠、环保社会组织弱小等,是我国大气污染治理中公众参与度低的主要原因,因此提出转变观念、完善机制、加强教育、支持和引导环保社会组织,促进公众参与的多元治理模式的形成,真正推动大气环境质量的改善。  相似文献   
819.
当前的长三角区域环境治理尽管取得了一定成效,但其治理成本过高且难以达到持久改善的效果。长三角环境污染的根源在于投资驱动型增长导致的结构性污染锁定,以及低端经济导致的能源升级障碍。因此,环境治理应着眼于区域增长方式转型和环境与发展关系的优化,关键问题在于如何改变经济增长的推动方式与路径依赖,如何在新常态经济格局下寻求新的经济增长点,以及如何协调好不同行政区划之间的利益冲突。当前长三角区域需建立区域一体化的环境协同治理机制,推进能源升级与产业去重化进程,促进地区间错位发展与联动发展,以新型城镇化调动新的增长潜力,结合智慧城市建设转变公共服务供给方式,优化城市布局。  相似文献   
820.
In conjunction with socioeconomic development in watersheds, increasingly challenging problems, such as scarcity of water resources and environmental deterioration, have arisen. Watershed management is a useful tool for dealing with these issues and maintaining sustainable development at the watershed scale. The complex and uncertain characteristics of watershed systems have a great impact on decisions about countermeasures and other techniques that will be applied in the future. An optimization method based on scenario analysis is proposed in this paper as a means of handling watershed management under uncertainty. This method integrates system analysis, forecast methods, and scenario analysis, as well as the contributions of stakeholders and experts, into a comprehensive framework. The proposed method comprises four steps: system analyses, a listing of potential engineering techniques and countermeasures, scenario analyses, and the optimal selection of countermeasures and engineering techniques. The proposed method was applied to the case of the Lake Qionghai watershed in southwestern China, and the results are reported in this paper. This case study demonstrates that the proposed method can be used to deal efficiently with uncertainties at the watershed level. Moreover, this method takes into consideration the interests of different groups, which is crucial for successful watershed management. In particular, social, economic, environmental, and resource systems are all considered in order to improve the applicability of the method. In short, the optimization method based on scenario analysis proposed here is a valuable tool for watershed management.  相似文献   
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