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971.
ABR-MBR一体化工艺节能降耗措施优化研究   总被引:3,自引:1,他引:2  
吴鹏  陆爽君  徐乐中  刘捷  沈耀良 《环境科学》2015,36(8):2934-2938
能耗高和膜污染是限制膜生物反应器(MBR)广泛应用的重要因素.为降低工艺运行能耗和延缓膜污染,以厌氧折流板反应器(ABR)-MBR工艺处理生活污水为例,对工艺结构和脱氮除磷运行条件进行优化.结果表明,通过优化ABR-MBR工艺结构,可降低43%的运行能耗,同时可保持较高的COD、NH+4-N、TN和TP去除效果,平均去除率分别为91%、85%、76%和86%.另外,添加颗粒填料可有效延缓膜污染,不过也改变了膜污染的形成过程,膜内部污染物含量显著增多,碳水化合物含量增加,而蛋白质含量减少,碳水化合物/蛋白质比明显增大.最终,增强了MBR反应器的实际应用性能.  相似文献   
972.
青藏铁路建设中高寒缺氧及保障问题的研讨   总被引:2,自引:1,他引:1  
“高寒缺氧”是青藏铁路建设面临的主要难题之一,青藏铁路沿线自然条件恶劣、海拔高、气压低,含氧量低,缺氧严重会导致急性高原病严重影响人体健康和劳动能力,同时含氧量低会造成机械功率降低。为保障高原施工人员和铁路建设者的健康和安全,降低机械设备的功率损耗,在青藏铁路的设计和建设中,必须采取高原劳动卫生和劳动保护措施、选用可靠度高、维修量少的运营设备,建立起适合高原特点的管理体制、机构及合理的用工制度等技术保障措施,提供坚强有力的医疗卫生保障,从而提高劳动效率,降低劳动强度、缩短工期,保护员工的安全与健康。  相似文献   
973.
污水厂污泥在不同氧气浓度下的热分析动力学特性研究   总被引:5,自引:2,他引:3  
为了解在不同氧气浓度下污泥的热解燃烧行为和动力学机理,利用热重差热分析仪,在不同氧气浓度下,对经过不同干燥温度干燥的污泥样品进行热重差热实验.通过分析氧气浓度和干燥温度对样品热分析曲线的影响发现,干燥温度对污泥样品热分析的影响很小,但氧气浓度对其有明显的影响;随着氧气浓度的增加,热分析曲线有规律的向左偏移.在此基础上,提出污泥在不同氧气浓度条件下3种物质独立反应的热化学反应动力学模型.在该模型中,3个阶段分别对应3种不同的物质独立反应.在各种氧气浓度条件下,这3种物质的反应过程均符合一级反应模型.随着氧气浓度的上升,3个阶段对应的活化能和频率因子呈现上升趋势.  相似文献   
974.
人工湿地氮转化与氧关系研究   总被引:20,自引:6,他引:14  
应用N转化迁移模型分析廊道式人工湿地氮转化与氧供应的关系,验证目前湿地全程硝化反硝化脱氮机制的有效性.对各个廊道进出水NH4+-N、NO3--N、TN、B5、DO进行了测定和分析.在水力负荷5cm/d条件下,各廊道湿地有机氮矿化率为0.01~0.28g·(m2·d)-1、氨氮硝化率0.50~1.54 g·(m2·d)-1,反硝化率0.41~1.13 g·(m2·d)-1(占总氮损失的3.4%~35.4%)、植物净吸收氮0.07~0.26 g·(m2·d)-1(占总氮损失的7%~33%).硝化反硝化与有机质降解同时进行,在进水端最明显,这与传统认识相悖.按照全程硝化化学计量学得到的硝化需氧量(NOD)高于实际的表面复氧和植物根系放氧.最后对在高浓度有机质存在条件下,能减少对氧需求的2种新型脱氮机制进行了讨论.  相似文献   
975.
测氧仪广泛用于石化行业的受限空间缺氧或富氧检测.在简要介绍测氧仪核心--伽伐尼氧气传感器工作原理的基础上,分析了影响毛细管式氧气传感器工作的主要因素,结合工作实践,提出了使用维护测氧仪的几条建议.  相似文献   
976.
Intergenerational conflict coordination is the fundamental requirement and core of sustainable development. In this paper, through the analysis of the future generations-oriented management mechanisms for intergenerational conflict, the idea of mechanisms and institution building for the coordination and management of intergenerational conflict is put forward. Furthermore, the future generations-oriented virtual negotiation support system (NSS) for intergenerational conflict is developed, built on the analysis of the process simulation of intergenerational wealth transfer, intergenerational equilibrium allocation of resources, and strategies for the mitigation and avoidance of intergenerational conflict, through the application of advanced IT technology. The virtual NSS for intergenerational conflict is helpful to the practical application of the sustainable development theory; on the other hand, it can be applied directly to the intergenerational equilibrium allocation of resources, national economic accounting, formulation of sustainable development strategies and other urgent national economic and social development issues. Finally, the sustainable development theory can be enriched and extended. Therefore, the development of the future generations-oriented virtual NSS for intergenerational conflict has certain theoretical and practical effects on the theory of sustainable development.  相似文献   
977.
The study on population and the resource-environment by the consumption may contribute to the further cognition about their correlations and provide the policy references for natural resources use and environmental protection. This article has studied the impact status of the consumption level difference of China's 31 provinces or autonomous regions on the resource-environment in 2005 by per capita consumption expenditure and serial statistical data with unit person method and constructed consumption model and hierarchical cluster analysis. We found several trends. To the intensity that population acting on the resource-environment, four sorts of regions might be divided in 2005, furthermore, most of them were at the level of unit person. Provinces or autonomous regions, located in the developed coastal areas in China, generally have the bigger impact intensity on the resource-environment than the others. That is to say, the natural resources mainly flow from west to east and from north to south, but the environmental loads are shared in the whole China and are likely to be aggravated from east to west reversely. The main causes of imbalance of pressure on the resource-environment should be the difference of consumption level, the unmatchable resource exploitation and utilization, the imbalance of discharging pollutants, and the difference of moderate carrying capacity. To the total impact quantities that population acting on the resource-environment, four sorts of regions were divided in 2005 and the difference of them was notable. Provinces or autonomous regions, having the bigger impact quantities on the resource-environment, are generally located in the eastern and central China while the extended western China is still the weak impact area of the resource-environment consumption or terminal pressure. Provinces or autonomous regions are few, where the total impact quantities are more or less; alternately, those are many, where the total impact quantities rank the middle.  相似文献   
978.
The western region is an important strategic base of energy in China. The average per capita possession of fossil energy in the west is twice that in China. On the basis of the analysis of the mechanism how industrial structure adjustment affects energy consumption per unit of gross domestic product (GDP), the energy input-output table of western China was designed and compiled. Combining multiobjective planning techniques, setting energy-saving, economic growth, and laborer's income growth as the goals, setting basic input-output relations, production capacity, and labor as the constraints, the multiobjective optimization model of western energy input-output was constructed. The results of industrial structure optimization of western China show that: with technology and product price remaining unchanged, the adjustment of the industrial structure can reduce energy consumption per unit GDP by 2.7%, at the same time ensuring the average annual increase of GDP and laborer's income of western region in excess of 8%. It indicates that industrial structure adjustment is an effective method in accomplishing the aim of energy saving. Finally, policy suggestions from four angles, such as industrial chain and financial policies, were put forward.  相似文献   
979.
Abstract

This paper reports on research designed to investigate the capacities of different highly characterized peats to remove odorous compounds from liquid swine manure (LSM). Peat types representing a wide range of properties were tested in order to establish which chemical and physical properties might be most indicative of their capacities to remediate odors produced by LSM. Eight percent slurries (of peat/LSM) were measured for odor changes after 24 hours using odor panel and GC/MS‐Solid‐phase microextraction (GC/MS‐SPME) analysis.

The GC/MS‐SPME and odor panel results indicated that, although all peats tested in this study were found to be effective at removing odor‐causing compounds found in LSM, some peats tended to work better than others. Overall, the peats that were the most effective at removing odor‐causing compounds tended to have lower bulk densities, ash contents, fulvic acids contents, and guaiacyl lignins contents,and higher water holding capacities, hydraulic conductivities, “total other lignins”; contents, hydrogen contents, carbon contents, and total cellulose contents.

GC/MS‐SPME analysis was found to be a reasonably inexpensive and efficient way of conducting this type of research. It allows one to identify a large number of the odor‐causing compounds found in LSM, and more importantly, to detect with some precision specific differences in the amounts of these compounds between peat types.  相似文献   
980.
Abstract

The purpose of this study was to investigate the T‐2 toxin contaminated grain and grain products consumed especially by Turkish population. The T‐2 toxin was detected using the high performance liquid chromatography (HPLC) with UV detector at 208 nm and the identify of T‐2 was further confirmed by thin layer chromatography (TLC). The recovery was 91 ±4.24% for corn flour fortified with the known amount of T‐2 toxin (1 ppm). The detection limits of T‐2 toxin for the HPLC and the TLC were 25 ng and 50 ng, respectively. A total of 30 commercially available grain and grain product samples were analyzed. Two corn flour samples were found to contain detectable levels of T‐2 toxin at a level of 1.60 ppm and 4.08 ppm.  相似文献   
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