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311.
采用新型高效催化氧化技术,在室内小试的基础上,将研究成果直接用于盘锦大兴化工有限公司高浓度COD的化工废水处理工程。  相似文献   
312.
针对实际运行条件下,国内生物质固体燃料燃烧过程中NO、CO排放研究不足,排放现状不清晰等问题,在天津地区选择了6台具有代表性的生物质固体燃料锅炉,在测试中燃烧其常用燃料,采用烟气分析仪Testo350对锅炉展开了气态排放研究,重点研究了其中5台生物质固体成型燃料锅炉在不同燃烧负荷下,NO和CO的排放情况,以及另1台捆烧式锅炉在正常工况下的排放情况。测试结果表明:6台生物质锅炉的NO排放浓度均在180 mg/m~3以上,CO排放浓度均高于500 mg/m~3。其中,3台炉型的固体成型燃料锅炉随着燃烧负荷的增大,NO排放浓度降低CO浓度升高,燃烧负荷控制在75%~80%可相对减少气态污染物NO、CO的排放,其余2台炉型NO、CO排放浓度随燃烧负荷的增大变化趋势与前3台相反,且燃烧负荷控制在95%左右为优;捆烧式锅炉NO排放浓度最低为182.9 mg/m~3,但CO排放浓度却高达2 243.6 mg/m~3。研究结果可为用生物质固体燃料锅炉的实际运行提供参考,从而优化生物质固态燃料的燃烧和排放。  相似文献   
313.
对LCA在玉米种植环境影响研究中的目标与范围定义、清单分析、环境影响指标与计算方法、结果解释等方面的研究进行了梳理分析,其中大部分文献均对碳足迹进行了计算,CML(Institute of Environmental Sciences of the University of Leiden)、ReCiPe(许多LCA领域研究人员共同开发)和IPCC(Intergovernmental Panel on Climate Change)方法是应用最多的3种方法,经分析计算得到国外玉米种植单位产量碳足迹均值为0.50kg CO2-eq/kg,我国的均值为0.58kg CO2-eq/kg.同时本文也对LCA在玉米深加工产品中的研究进展进行了分析整理,对今后LCA应用于玉米种植及深加工产品中的发展方向进行了展望.  相似文献   
314.
某污水处理厂方案设计简介   总被引:1,自引:0,他引:1  
随着生活水平的不断提高,人们的环保意识正在逐渐增强,目前大中型城市建设污水处理集中设施十分普遍,但对于小城镇来说,如何选择经济、安全、稳定的污水处理工艺,是各主管部门和设计单位面临的迫切问题.虽然传统活性污泥工艺具有运行可靠、操作简便等特点,但由于其占地多、出水水质差,已不能适应当前国家越来越严格的出水水质排放标准.本文以某小型污水处理厂工艺选择为例,希望为有关人员提供借鉴.  相似文献   
315.
ABSTRACT: Extensive investigations have been undertaken to determine the utility of Landsat data for detecting and analyzing hydrologic characteristics of an interior watershed of Iran that drains to Daryachehye-Namak (salt lake). This interior playa serves as the terminus for surface water discharging to it from the Karaj, Shur, Saveh, and Ghom Rivers and ground water from their underlying aquifers. These drainage systems encompass heavily populated and industrial sectors of west central Iran, including Tehran. The result of this investigation demonstrates the applicability of Landsat data for mapping and monitoring water regimen as an aid in interpreting hydrologic conditions throughout this arid region. Fluctuation of water area in a playa lake, occupying the lowest part of this closed basin, was monitored on repetitive Landsat coverage. As the result of field investigations combined with optical and digital analyses of the Landsat data, fluctuating water depths were determined in order to estimate the volume of water present in this lake during various seasons. A comparison between stream discharge rates and the estimated volume of standing water make it possible to quantitatively evaluate the hydrologic regimen and to detect the significance of ground water discharge.  相似文献   
316.
This contribution describes characterization, classification, production, application and quality assurance of Refuse Derived Fuels (RDFs) that are increasingly used in a wide range of co-incineration plants. It is shown in this paper, that the fuel-parameter, i.e. net calorific value [MJ/kgOS], particle size d90 or d95 [mm], impurities [w%], chlorine content [w%], sulfur content [w%], fluorine content [w%], ash content [w%], moisture [w%] and heavy metals content [mg/kgDM], can be preferentially used for the classification of different types of RDF applied for co-incineration and substitution of fossil-fuel in different industial sectors. Describing the external production of RDF by processing and confectioning of wastes as well as internal processing of waste at the incineration plant, a case study is reported on the application of RDF made out of different household waste fractions in a 120,000 t/yr Waste to Energy (WtE) circulating fluidized bed (CFB) incinerator. For that purpose, delivered wastes, as well as incinerator feedstock material (i.e. after internal waste processing) are extensively investigated. Starting with elaboration of sampling plan in accordance with the relevant guidelines and standards, waste from different suppliers was sampled. Moreover, manual sorting analyses and chemical analyses were carried out. Finally, results of investigations are presented and discussed in the paper.  相似文献   
317.
This paper presents the results of a study of a sludge subjected to the (ATAD) process – Autothermal Thermophilic Aerobic Digestion occurring in a two-stage installation operated in a municipal wastewater treatment plant in Olecko, Poland. The study of the sludge and the analysis of obtained results were conducted over 2011 and 2014. The subject of the study was a thickened sludge in an intermediate tank from which it was next transferred to facility reactors. The stabilization of processed sludge was evaluated analyzing the change in the dry mass (DS) content in the sludge. Measurements were carried out in thickened sludge samples and after the ATAD process. Collected results were then subjected to a statistical analysis and it was determined to which extent as resulted from the subject process the dry mass and the dry organic mass (VS) content was changing in the sludge. Also, it was analyzed how the oxygen chemical demand (COD) was changing. The dry mass content in the thickened sludge was from 60 g/l to 160 g/l. After the process, this amount was from 35 to 76 g/l. Similarly, the organic mass content in a dry sludge mass changed from initial values within a range of 44–135 g/l to 23–60 g/l after the ATAD process. Also, the organic substance content expressed as COD decreased from 80 to 467 g O2/l in a thickened sludge to 51–261 g O2/l in the sludge after the process. The article presents conclusions from the result of the conducted study as well as personal experience.  相似文献   
318.
突发灾害救援工作的展开依赖于快速有效的应急损失评估,其技术过程是指快速获取因突发灾害而造成的各类工程结构物的破坏和人员伤亡等灾害现场信息。为此,提出利用广泛布设于城市道路、公共场所、构(建)筑物内部的视频监控设备所捕捉到的影像资料,在技术上通过计算机图像处理技术,结合灾害快速评估技术和地理信息系统(GIS),对灾害现场以构(建)筑物为代表的工程设施进行监测,提供实时的数据处理结果和现场灾害快速评估信息,从而在最大程度上避免突发灾害救援指挥的无序性,提高应急工作效率。  相似文献   
319.
实际应用的饮食业油烟净化设备(以下简称油烟净化设备)中,以静电式、机械过滤式、湿式,以及由上述三种技术组成的复合式产品为主。荷电湿式油烟净化器的开发应用,将具有很强的市场竞争力,未来几年,静电式技术将继续被广泛采用,机械式技术将更多地作为预处理手段与其他技术组合使用,湿法技术因兼有部分除味和去除柴油灶燃烧颗粒的功能等特点将更有针对性地应用于适当的场所。优化组合而成的经济高效的复合式技术在未来市场中将占据主导地位。  相似文献   
320.
Dispersion models require as input various geometrical parameters to calculate the flow field and dispersion characteristics in the urban environment. As a result of recent advances in digital photogrammetry and remote sensing, databases of the actual 3-D geometry of city centre areas are now increasingly available. In this work we outline a procedure to reduce this large amount of data to a structured input for urban pollution dispersion models, i.e. to extract the important flow and dispersion parameters from the urban databases. Based on a review of the scientific literature, we have identified a number of parameters relevant to the modelling of pollution dispersion and atmospheric flows in urban areas. These parameters are: the plan and frontal area densities, the plan and frontal area density as a function of height, the distribution of heights, their standard deviation, the aerodynamic roughness length and the sky view factor.These parameters are obtained by analysing urban Digital Elevation Models (DEMs) which are regularly spaced grids of elevation values. Examples of the parameters calculated from high-resolution databases (with pixel size of about 1 m) for three European (London, Toulouse and Berlin) and two North American (Salt Lake City and Los Angeles) cities are presented and discussed. The calculated aerodynamic roughness length was smaller for the European cities than for the North American ones. A multiplicative correction factor to the aerodynamic roughness length is proposed to include the effect of the variability of the building heights.  相似文献   
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