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251.
我国医疗废物集中处置行业呈现多种投资来源和多种运营模式并存的格局,医疗废物集中处置设施建设和运营主要采用以BOT为主的特许经营模式,部分设施由于模式选择不当,导致产权边界不清、稳定运行困难等问题,一定程度限制了行业的可持续发展。近年来开始应用于我国污水处理设施的DBO模式具有责任主体一致、建设运营效率较高等特点,在环境污染治理领域的应用前景较为广阔。本文通过对DBO模式和BOT模式的所有权归属、责任主体、实施期限等方面进行对比,分析得出DBO模式较BOT模式在设施的运营阶段具有突出优势,应用于医疗废物集中处置设施可以更有效地保证运营效率、节约财政支出、强化政府监管。同时,预期在医疗废物集中处置项目中推行DBO模式可能存在的阻碍,包括政府积极性不高、招商面临一定难度、实施过程的不确定因素较多等,并有针对性提出了在中小城市开展试点、发放环境基础设施建设债券、邻近区域多个项目捆绑招商等建议,以促进DBO模式在医疗废物集中处置设施中的应用。 相似文献
252.
Muhammad Aqeel Kamran Amna Rabia Mufti Nadia Mubariz Jabir Hussain Syed Asghari Bano Muhammad Tariq Javed Muhammad Farooq Hussain Munis Zhiyuan Tan Hassan Javed Chaudhary 《Environmental science and pollution research international》2014,21(2):801-812
Soil and water quality is greatly affected by environmental pollution due to the increasing trend of urbanization and industrialization. In many developing countries, including Pakistan, the situation is more alarming as no preventive measures are still taken to tackle the problem. Although in developed countries, many techniques are used to remediate the environment including phytoremediation. It is the most eco-friendly technique in which plants are used to remove pollutants from the environment. Pakistan has also a great diversity of plants which could be used for the remediation of environmental pollutants. To our knowledge, few studies from Pakistan were reported about the use of flora for phytoremediation. According to recent literature, 50 plant species from Pakistan are studied for remediation purposes. In this review, the potential of different plant species for phytoremediation from Pakistan has been discussed along with their comparison to other countries to relate future perspectives. 相似文献
253.
Wei Jiang Qingye Hou Zhongfang Yang Tao Yu Cong Zhong Yi Yang Yangrong Fu 《Environmental science and pollution research international》2014,21(13):7876-7885
The accumulation of heavy metals in farmland has become an important issue related to food security and environmental risk. The annual inputs of heavy metals (As, Cd, Hg, Pb, Cr, Cu, and Zn) to agricultural soil for a full year in Hainan Island have been studied. Three fluxes through the cultivated horizon were considered: (1) atmospheric depositions, (2) fertilization, and (3) irrigation water. The corresponding samples were collected and analyzed on a large regional scale. The total input fluxes show obvious spatial variability among different regions. The inventory of heavy metal inputs to agricultural land demonstrates that agricultural soil is potentially at risk of heavy metal accumulation from irrigation water. The potential at risk of heavy metal accumulation from atmospheric deposition and fertilizer is relatively low compared to irrigation. The results indicate that Hg is the element of prior concern for agricultural soil, followed by Cd and As, and other heavy metal elements represent little threat to the environment in the study area. This work provides baseline information to develop policies to control and reduce toxic elements accumulated in agricultural soil. 相似文献
254.
Cong Zhong Zhongfang Yang Wei Jiang Tao Yu Qingye Hou Desheng Li Jianwu Wang 《Environmental science and pollution research international》2014,21(21):12305-12315
Industrialization and urbanization have led to a great deterioration of air quality and provoked some serious environmental concerns. One hundred and five samples of atmospheric deposition were analyzed for their concentrations of 13 trace elements (As, Cd, Cu, Fe, Al, Co, Cr, Hg, Mn, Mo, Pb, Se, and Zn) in Shanxi Basin, which includes six isolate basins. The input fluxes of the trace elements in atmospheric deposition were observed and evaluated. Geostatistical analysis (EF, PCA, and CA ) were conducted to determine the spatial distribution, possible sources, and enrichment degrees of trace elements in atmospheric deposition. Fe/Al and K/Al also contribute to identify the sources of atmospheric deposition. The distribution of trace elements in atmospheric deposition was proved to be geographically restricted. The results show that As, Cd, Pb, Zn, and Se mainly come from coal combustion. Fe, Cu, Mn, Hg, and Co originate mainly from interactions between local polluted soils and blowing dust from other places, while the main source of Al, Cr, and Mo are the soil parent materials without pollution. This work provides baseline information to develop policies to control and reduce trace elements, especially toxic elements, from atmospheric deposition. Some exploratory analytical methods applied in this work are also worth considering in similar researches. 相似文献
255.
UV_(254)在煤制气废水处理中的指示作用 总被引:1,自引:0,他引:1
鉴于UV254具有操作简单、测定速度快、成本低和重现性好等优点,对UV254在煤制气废水处理中监测与指示作用进行了分析研究。结果表明,煤制气废水水质比较复杂,在各个处理单元中,COD和UV254的相关系数最高仅为0.8328,相关性不高,UV254不适合代替COD作为日常监测指标。在臭氧深度处理煤制气废水的实验中,COD与UV254相关系数为0.9826和0.9812,在煤制气废水处理工艺中沿程COD和UV254相关系数为0.9879。结果表明,在水质一定的情况下进行废水处理过程中,UV254与COD的变化趋势高度一致,具有显著的相关性,UV254可以作为预测COD去除效果的指示指标,这在将在较大程度上节约时间和降低实验成本。 相似文献
256.
以乙二胺(EDA)还原氧化石墨烯(GO)制得一种吸附剂材料,即还原态氧化石墨烯(RGO)。考察了动态条件下Cd2+溶液的初始浓度、流速及吸附床高度对穿透曲线的影响,同时利用Bed-Depth-Service Time(BDST)模型对吸附床高度与穿透时间的关系进行线性拟合分析,研究了RGO对Cd2+溶液的动态吸附性能。结果表明,RGO可以有效地去除水溶液中的Cd2+,随着吸附床高度的增加,离子的去除率增大,穿透时间延长;当溶液初始浓度增大时穿透时间缩短,离子的去除率减小;而溶液的流速加快,穿透时间和去除率都相应减小。吸附床高度与穿透时间的关系可用BDST模型较好地进行描述,预测新的操作条件下的穿透时间与实验值误差均小于5%。 相似文献
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259.
对国家环境保护野外观测研究站建设的几点思考 总被引:1,自引:0,他引:1
《国家环境保护"十二五"科技发展规划》提出将国家环境保护野外观测研究站作为"十二五"环境科技支撑能力建设内容之一;在《"十二五"国家自主创新能力建设规划》中也将国家野外科学观测研究站(网)作为科技创新基础条件的建设内容。在分析环保部门生态环境观测研究台站建设现状基础上,对国家环境保护野外观测研究台站的建设目标与定位、空间布局、运行机制、监测与评价技术体系构建、监测指标体系框架等进行分析探讨。在目标与定位上,国家环境保护野外观测研究台站既要与目前国内主要的生态环境监测网络(如中国生态系统研究网络和中国森林生态系统定位研究网络)形成补充,同时也要突出环保部门特色;在空间布局上既要关注水、空气、土壤污染的重点监控区,也要关注生态脆弱区、重要(点)生态功能区等生态敏感区;在技术体系上,要研究建立标准化、规范化的观测技术体系,同时也要注重生态环境评价方法研究,为生态环境精准化管理提供技术支持。 相似文献
260.