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101.
曙光油田节能减排现状调查及对策研究   总被引:1,自引:1,他引:0  
曙光采油厂随着超稠油的不断开发,生产能耗也随之增加,通过开展节能减排及节能挖潜工作,全厂能耗增长状态得到了良好的控制,能耗总量由2005年的58.21×10~4t标煤下降到2008年的47.75×10~4t标煤;原油(气)液生产单位综合能耗为52.02 kg标煤/t,同期对比减少0.38 kg标煤/t;生产系统运行效率不断提高。文章详细介绍了曙光油田从机采系统、热注系统、集输系统等方面推广应用节能新技术、新产品,达到其投资和运行费用最少,经济性较好,对油田减排挖潜进行了探讨。  相似文献   
102.
基于层次分析法的秦皇岛市垃圾填埋场选址评价   总被引:1,自引:0,他引:1  
城市垃圾填埋场场址的选择,受到当地经济、交通、气候条件,自然地理条件,环境保护条件,水文地质工程地质条件等诸多因素影响,是一项十分复杂的工程。本文总结了秦皇岛市现有垃圾填埋场的基本情况、存在问题及其产生原因。鉴于层次分析法在多目标决策分析方面的成效,将其运用到秦皇岛市垃圾填埋场选址评价中,对研究区进行适宜性分区,依次划分为最佳场地区、适宜场地区、较适宜场地区、不适宜场地区。  相似文献   
103.
NaCl和KCl对厌氧污泥抑制的动力学研究   总被引:2,自引:0,他引:2  
在厌氧颗粒污泥和厌氧絮状污泥系统中,进行盐质量浓度(NaCl或KCl质量浓度,下同)对厌氧污泥抑制动力学的研究,得到不同拟合的COD降解动力学方程及参数.实验结果表明:当盐质量浓度为10~30 g/L时,KCl对厌氧污泥的COD比降解速率的抑制程度大于NaCl;当盐质量浓度由0 g/L增至10 g/L时,半速率常数逐渐增加;当盐质量浓度由10 g/L增至30 g/L时,半速率常数逐渐减小;在厌氧污泥系统中,NaCl抑制作用下的盐抑制常数高于KCl,且颗粒污泥的盐抑制常数高于絮状污泥.  相似文献   
104.
The thermoplastic starch (TPS) and nanocomposite(TPS/OMMT) was prepared with 15% carbamide, 15% ethanolamine and different contents of organic activated montmorillonite (OMMT) by twin-screw extruder with a 130 °C barrel temperature. Fourier transforms infrared spectroscopy and wide angle X-ray diffraction shown that the alkylamine in dodecyl benzyl dimethyl ammonium bromide could react with MMT via cation exchange reaction. After treated, the d(001)space distance of MMT increased from 1.5 to 1.7 nm. Scanning electron microscope revealed that the lower contents of OMMT could disperse well in the matrixes of TPS. The carbamide, ethanolamine and the OMMT could destroy the crystallization behavior of starch, but only the OMMT restrained this behavior for long-term storing. Mechanical properties investigation indicated that the tensile strength and modulus of TPS/OMMT nanocomposites were better than those of TPS, while the elongation at break was descended with the increasing of OMMT contents. When the content of OMMT was 4%, the tensile strength and modulus of TPS was improved from 4.2 and 42 MPa to 6.0 and 76 MPa, respectively.  相似文献   
105.
Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and other organic micropollutants were determined in dated sediment/soil cores collected from the flood-plain of the river Elbe near Pevestorf (PT), approximately 125 km upstream of Hamburg, and Heuckenlock (HL) in southeast of Hamburg. Concentrations of PCDD/Fs peaked sharply at PT in the 1950s and at HL at the end of the 1940s. Cluster analyses provide evidence that the region of Bitterfeld-Wolfen (about 350-400 km upstream of Hamburg) could be the source of the PCDD/F contamination existing in the cores PT and HL since the 1940s. Obviously it is caused by sediments of the river Elbe of a similar composition. Whereas the PCDD/Fs, HCHs (hexacyclohexane isomers), DDX (DDT, DDD, DDE), and tetrachlorinated ethers in PT and HL presumably originated predominantly from the Bitterfeld-Wolfen region, organotin compounds in HL and dichlorinated haloethers in HL during the 1940s and 1950s can probably largely be attributed to emissions from the Hamburg region. Although they are separated by a large distance, in both sediment cores PT and HL concentrations and composition patterns of most organic micropollutants analyzed widely match. Inductively it can be concluded that similar contaminations will be found in many of the river bank soils between the Bitterfeld-Wolfen region and Hamburg. Excavation of top soils may uncover highly contaminated materials. Since the dated sediment cores show the variation in contaminants in the Elbe sediments over a defined time period, it is possible to make an approximate assessment of the actual degree of contamination to be expected in areas where in previous decades contaminated dredged sediments from the Elbe and from the Port of Hamburg have been deposited on land and used for building plots or for agricultural purposes.  相似文献   
106.
应用层次分析法分析当代大学生心理安全影响因素,首先要把问题条理化、层次化,弄清问题的范围,所包含的因素,因素之间的相互关联、隶属关系,最终确定所要解决的问题等。它对大学生心理问题产生的各方面原因进行综合评价,找出其中3个最重要的因子——恋爱方面的困扰、对学校教育方式的不适应以及严重的躯体疾病。针对大学生心理安全问题形成的原因,试图提出解决问题的对策和建议,为提高当代大学生的社会适应能力,开发心理潜能,探索大学生心理健康教育的模式,提供理论依据。  相似文献   
107.
稻草制浆黑液生物+混凝处理试验   总被引:4,自引:0,他引:4  
通过对稻草制浆黑液厌氧、好氧、混凝处理组合工艺的试验研究,探索该工艺的可行性,考察了不同温度、不同有机负荷下,该类废水的生物处理效果以及后续混凝效果。结果表明:中温35℃是厌氧阶段最佳处理温度,好氧阶段不同负荷条件下,CODCr去除率基本相同;经厌氧-好氧处理,黑液CODCr和木质素去除率分别为80%和30%,色度去除不明显;混凝阶段CODCr和木质素去除率分别为70%和90%,色度去除率达90%以上,出水达到国家标准。  相似文献   
108.
Oxidative stress (OS) and fluctuating asymmetry (FA) as risk markers for environmental stress are widely used to predict changes in the health and fitness of many animals exposed to pollutants. However, from the perspective of protecting declining amphibians, it remains to be verified which one would be a reliable indicator for amphibians exposed to long-term heavy metal pollution under natural conditions. In this study, the OS and FA of Bufo raddei exposed to natural heavy metal pollution were analyzed to determine which marker is more accurate for indicating heavy metal-induced stress. Three years of data were collected during the breeding season of B. raddei from Baiyin (BY), which has been mainly contaminated with Cu, Zn, Pb, and Cd compounds for a long period, and from Liujiaxia (LJX), which is a relatively unpolluted area. Unexpectedly, although significant accumulation of the four heavy metals was found in the kidney and liver of B. raddei from BY, the levels of superoxide dismutase, glutathione peroxidase, and malondialdehyde in these two organs were found to be irregular, with low repeatability in both BY and LJX. However, significant differences in the levels of FA were observed in B. raddei populations from these two areas over the past 3 years (P < 0.01). The degrees of FA in B. raddei populations from BY and LJX were assessed as degree 4 and 1, respectively. In short, this study suggested that FA was a more reliable and effective indicator than OS to monitor and predict long-term environmental stress on anuran amphibians.  相似文献   
109.
110.
2013—2014年,逐次采集淮南城市大气降水样品,对其离子化学组分进行分析测试,并利用酸度分析、中和因子和富集系数等方法对其酸碱物质平衡和离子来源进行了分析。化学组分分析结果表明,淮南城市降水pH为6.23~7.03,雨量加权平均值为6.68,整体上降水没有呈现酸化,大部分酸性物质能被碱性物质中和。主要阴离子为SO_4~(2-)、NO_3~-,雨量加权平均值分别为147.02、62.16μeq/L,两者分别占阴离子总浓度的60.3%、25.3%;主要阳离子为Ca~(2+)、NH_4~+,雨量加权平均值分别为126.42、96.43μeq/L,分别占阳离子总浓度的44.9%、34.3%。利用富集系数法计算结果表明,SO_4~(2-)、NO_3~-主要来源于人为活动排放,Cl~-主要为海洋输入,而Ca~(2+)、Mg~(2+)、K~+则主要来自陆源输入和人为活动。  相似文献   
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