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101.
厌氧水解改善富马酸废水的可生化性研究   总被引:12,自引:0,他引:12  
炼油厂产生的难于生物降解的富马酸废水 ,其BOD5/CODcr均值 (比值平均值 )仅为 0 .2 83。采用厌氧水解对其进行处理 ,实验研究表明 :通过厌氧水解 ,其BOD5/CODcr可提高至 0 .433 ,废水的可生化性显著提高 ,为后续好氧处理创造了有利条件。  相似文献   
102.
Hydrogen storage and transportation or distribution is closely linked together. Hydrogen can be distributed continuously in pipelines or batch wise by ships, trucks, railway or airplanes. All batch transportation requires a storage system but also pipelines can be used as pressure storage system. Hydrogen exhibits the highest heating value per weight of all chemical fuels. Furthermore, hydrogen is regenerative and environment friendly. There are two reasons why hydrogen is not the major fuel of toady’s energy consumption: First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water. This implies that we have to pay for this energy, which results in a difficult economic task, because since the industrialization we are used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is the low critical temperature of 33 K, i.e. hydrogen is a gas at room temperature. For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage system is crucial. Hydrogen can be stored by six different methods and phenomena: high pressure gas cylinders (up to 800 bar), liquid hydrogen in cryogenic tanks (at 21 K), adsorbed hydrogen on materials with a large specific surface area (at T < 100 K), absorbed on interstitial sites in a host metal (at ambient pressure and temperature), chemically bond in covalent and ionic compounds (at ambient pressure), oxidation of reactive metals e.g. Li, Na, Mg, Al, Zn with water. These metals easily react with water to the corresponding hydroxide and liberate the hydrogen from the water. Finally, the metal hydroxides can be thermally reduced to the metals in a solar furnace.  相似文献   
103.
介绍了葫芦岛市生态环境现状及主要问题,分析了各种生态问题产生的原因,阐述了保护和建设生态环境的主要对策。  相似文献   
104.
对城市生活垃圾进行资源化处理,不仅有利于解决城市生活垃圾所带来的城市生态环境问题,而且能够获取部分城市发展所需的资源,是发展循环经济的重要环节之一。从武汉市城市生活垃圾资源化处理的现状入手,对武汉市城市生活垃圾在回收再利用、焚烧发电、堆肥等方面的资源化处理措施予以分析,指出武汉市应优先开展回收再利用,适度发展焚烧发电和堆肥的规模,并在此基础上借鉴日本、美国和德国等国城市生活垃圾资源化处理的先进经验,提出要提高城市生活垃圾回收的比率和效率,推进城市生活垃圾资源化处理的产业化发展,以促进武汉市城市生活垃圾的资源化处理进程。  相似文献   
105.
基于资源最优化回收的再制造工程   总被引:6,自引:0,他引:6  
从对寿命末端产品的处理选择分析出发,建立了末端产品回收梯级模型,提出基于最优化产品末端回收选择的再制造工程回收的附加值最大,环境污染最小,综合效益最高,并分析了再制造在产品全寿命周期各阶段所发挥的重要作用。  相似文献   
106.
本研究以新疆开都—孔雀河流域为研究区,针对流域不同保护目标,采用定额法、阿克苏水平衡站公式和阿维里扬诺夫公式三种方法,分别估算了生态红线区和生态敏感区的生态需水量。研究结果表明开都—孔雀河流域生态红线区平均需水量为13.82×10~8m~3,生态敏感区平均生态需水量为2.06×10~8m~3,且潜水蒸发法中的阿克苏水平衡站公式的计算值与平均值最为接近。由于干旱区降水量稀少,天然植被生长完全依赖地下水,一般采用潜水蒸发法间接计算植被的生态需水量,在植被需水定额不好确定的情况下,更是首选潜水蒸发法进行生态需水量的估算。研究成果可以为孔雀河生态输水工程和塔里木河下游生态输水工程的实施提供科学依据。  相似文献   
107.
The reestablisment of autochthonous plant species is an essential strategy for recovering degraded areas under semiarid conditions. A field experiment was carried out to assess the short-term effect of two reafforestation methods involving mycorrhizal inoculation and compost addition on soil quality parameters and Rhamnus lycioides seedling growth. The nutrient content (NPK) and enzymatic activities (dehydrogenase, urease, protease-BAA, acid phosphatase and β-glucosidase) increased and bulk density decreased in the rhizosphere soil with the organic amendment. Biomass C of rhizosphere soil increased by at least 240% with respect to the control soil after mycorrhizal inoculation and the combination of compost addition + mycorrhizal inoculation. Both mycorrhizal inoculation and composted organic residue addition increased R. lycioides seedling growth in the same proportion. In the short term, we conclude that the application of both reafforestation methods not only enhances the establishment of R. lycioides seedlings, but also improves soil quality.  相似文献   
108.
化学混凝-SBR法处理肉禽屠宰废水的研究   总被引:7,自引:0,他引:7  
针对肉禽屠宰废水的特点,采取了先混凝后生化的处理方法。在实验中确定了最佳混凝剂和最佳工艺条件。实验结果表明,采取此方法处理肉禽屠宰废水,其各项指标可达国家规定的排放标准。  相似文献   
109.
 The effect of the soil solids concentration in batch tests on the measured values of the partition coefficient (K p) of organic pollutants in landfill liner-soil material was investigated. Since this study was based on the results of batch and column tests conducted independently, there were limitations to the conclusions derived. The organic compounds tested were benzene, methylene chloride, toluene, trichloroethylene, and p-xylene. The results of this study showed that as soil solids concentrations increased, the measured K p values of these organic compounds strongly decreased. The observed values of K p stabilized when the soil solids concentration was above a certain value. Typical K p values obtained from batch tests conducted under high soil solids concentrations were close to those obtained from column tests. It was concluded that the K p values of organic compounds measured under low soil solids concentrations, i.e., less than 100 g/l, may not correctly simulate the field situation. Consequently, the values of K p obtained with low soil solids concentrations can result in an overestimation of the retardation factor of the landfill liner material. Received: March 14, 2002 / Accepted: August 25, 2002  相似文献   
110.
ABSTRACT: A grid based daily hydrologic model for a watershed with paddy fields was developed to predict the stream discharge. ASCII formatted elevation, soil, and land use data supported by the GRASS Geographic Information System are used to generate distributed results such as surface runoff and subsurface flow, soil water content, and evapotranspiration. The model uses a single flow path algorithm and simulates a water balance at each grid element. A linear reservoir assumption was used to predict subsurface runoff components. The model was applied to a 75.6 km2 watershed located in the middle of South Korea, and observed stream flow hydrographs from 1995 and 1996 were compared to model predictions. The stream flow predictions of 1995 and 1996 generally agreed with the observed flow, resulting in a Nash‐Sutcliffe efficiency R2 of 0.60 and 0.62, respectively. The hydraulic conductivity for percolating water through the saturated layer affected baseflow generation. The levee height of the paddy influenced the time and magnitude of the surface runoff, depending on irrigation management. The model will be used for making low flow management decisions by evaluating the role of each land use to stream flow, especially in case of paddy decrease by gradual urbanization of a watershed.  相似文献   
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