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951.
952.
Yanjun Meng Dazhen Tang Hao Xu Yong Li Lijun Gao 《Environmental science and pollution research international》2014,21(11):6964-6974
As one of the unconventional natural gas family members, coalbed methane (CBM) receives great attention throughout the world. The major associated problem of CBM production is the management of produced water. In the USA, Canada, and Australia, much research has been done on the effects and management of coalbed methane produced water (CMPW). However, in China, the environmental effects of CMPW were overlooked. The quantity and the quality of CMPW both vary enormously between coal basins or stratigraphic units in China. The unit produced water volume of CBM wells in China ranges from 10 to 271,280 L/well/day, and the concentration of total dissolved solids (TDS) ranges from 691 to 93,898 mg/L. Most pH values of CMPW are more than 7.0, showing the alkaline feature, and the Na-HCO3 and Na-HCO3-Cl are typical types of CMPW in China. Treatment and utilization of CMPW in China lag far behind the USA and Australia, and CMPW is mainly managed by surface impoundments and evaporation. Currently, the core environmental issues associated with CMPW in China are that the potential environmental problems of CMPW have not been given enough attention, and relevant regulations as well as environmental impact assessment (EIA) guidelines for CMPW are still lacking. Other potential issues in China includes (1) water quality monitoring issues for CMPW with special components in special areas, (2) groundwater level decline issues associated with the dewatering process, and (3) potential environmental issues of groundwater pollution associated with hydraulic fracturing. 相似文献
953.
954.
Yuanfang Wang Baoyu Gao Qinyan Yue Xiao Zhan Xiaohui Si Chunxiao Li 《Journal of environmental management》2009,90(2):423-431
Epichlorohydrin-dimethylamine polymers with different intrinsic viscosity (η) and cationicity (τ) were synthesized. The flocculation performance and mechanism of these polymers in the removal of the reactive and disperse dyes from synthetic wastewater was investigated in terms of flocculation dynamics and color removal efficiency. The polymer flocculation efficiency was compared with that of polyaluminum chloride (PAC) and a composite flocculant based on polyaluminum chloride-epichlorohydrin-dimethylamine polyamine. The results showed that epichlorohydrin-dimethylamine polymer was effective over a pH range of 2–10 for the reactive and disperse dye removal (Reactive Brilliant Red and Disperse Yellow dyes). Epichlorohydrin-dimethylamine polymer with the highest η and τ gave the best reactive dye removal efficiency, and its adsorption-bridging and electric neutralization ability played important roles in the flocculation process. The higher the η viscosity of the epichlorohydrin-dimethylamine polymer, the better the flocculation performance of epichlorohydrin-dimethylamine polyamine, and stronger adsorption-bridging ability was obtained for removing the disperse dye from dyeing wastewaters. Epichlorohydrin-dimethylamine polymer achieved better decolorization performance when used together with PAC. 相似文献
955.
Effects of hydrodynamics on the distribution of trace persistent organic pollutants and macrobenthic communities in Bohai Bay 总被引:4,自引:0,他引:4
In recent years, the rapid economic development along Bohai Bay, has brought out continuous increasing of the pollution loads in the Bohai Sea, especially by the large coastal reclamation project, Tianjin Binhai New Area. In the period of 2007-2009, we collected the sediments of the main rivers, estuaries, intertidal zone, and near-shore area of Bohai Bay, and Macrobenthos associated with the marine sediments to assess the influence of hydrodynamics in the coastal environment on the pattern of trace contaminants and the macrobenthic community. Based on data derived from these samples, the levels of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in sediments followed the order PAHs > OCPs > PCBs > PBDEs. The higher concentrations of PCBs, OCPs, PAHs and PBDEs were found in the estuarine and near-shore environment of the Dagu Drainage River. The spatial distribution of OCPs was different to that of PCBs due to the direction of the velocity field of Bohai Bay in its old and new topography, and the higher water-solubility of OCPs than that of PCBs. The results of the Pearson correlation and the PCA indicate that the medium diameter (MD) of sediments was the predominant factor influencing the distribution of PCBs and OCPs, most sampling sites were characterized mainly by TOC of sediments and biomass of macrobenthos. The results indicate that the distribution of trace contaminants and macrobenthic community in Bohai Bay are mainly affected by the hydrodynamic conditions. 相似文献
956.
Health institutions in the People's Republic of China are under considerable challenge. Innovations in management systems may support the challenge to increase both efficiency and effectiveness. The balanced scorecard (BSC) is one such innovation. We have used a model to explore the factors that may impact the diffusion of the BSC in Chinese government hospitals. In particular, we concentrate on three factors - the outer context, the nature of the innovation and the communication and influence. The outer context and the nature of the innovation do provide an inducement to implement a BSC. The strength of the communication and influence may affect the level of take-up. However, we recognise that they may choose "the BSC not for any apparent technical excellence but for the legitimation that Western management practices may bring to local managers. 相似文献
957.
958.
以曼么村为例 ,从环境经济学的观点出发 ,对热带森林 -砂仁生态系统的可持续性从经济及环境、生态等方面进行了分析。发现种植砂仁后 ,砂仁的经济效益的递增率不如资源环境成本的递增率快。生态环境的破坏 ,大大降低了砂仁的产量 ,从而更使得种植砂仁的经济效益停滞不前。由砂仁的外延式生产转为内涵式生产 ,采用轮作的经营方式 ,能很好地实现砂仁的持续种植 相似文献
959.
960.
通过资料调研、现场调查与检测,将获取的资料与法律、法规和标准要求相比较,对某炼化企业催化汽油吸附脱硫装置进行了职业病危害控制效果评价。 相似文献