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131.
依据美国环保署颁布的储罐VOCs排放量核算公式,从环境参数、原油参数和储罐结构参数3个方面对外浮顶储罐VOCs排放的影响进行了研究,其中包括了边缘密封排放挂壁排放、浮盘附件排放和浮盘着陆期间排放等几个相关排放核算数学公式。结果表明:环境风速增大,环境温度升高或太阳辐射强度提高均导致排放量增大;原油温度升高或原油周转量增加也导致排放量增加;储罐直径增加,罐漆颜色浅,或者罐壁锈蚀情况好会降低VOCs排放量。  相似文献   
132.
用Micaps实时资料、CPAS卫星反演分析资料、NCEP再分析资料、ECMWF再分析资料,多普勒雷达PUP产品资料,对2015年12月1日夜间至2日凌晨沈阳地区罕见冬季降雨过程,进行了天气学分析、及大气微物理人工增雨作业条件分析,并结合沈阳地区人工增雨作业指标,得出本次降雨过程在厄尔尼诺正在发生的背景下,为常见的高空槽转东北冷涡型,水汽、动力等微物理作业条件也适合于开展人工增雨作业,并给出了相应的作业指导参数,为沈阳地区今后在冬季降雨天气过程中开展人工增雨作业积累了宝贵经验.  相似文献   
133.
利用表面负载的方法将有机化磁性凹土与苯乙烯、二乙烯苯等制备磁性凹土树脂;对磁性凹土树脂进行氯甲基化改性,制备出氯化磁性凹土树脂.表征了样品的形貌、结构以及表面积,研究了树脂对天然有机物(腐殖酸)的吸附性能.结果表明:氯化后的磁性凹土树脂的比表面积是原有的1.9倍,对附腐殖酸的饱和吸附能力也从原有的41.84 mg/g提高到了51.02 mg/g,这表明改性后的树脂增强了其对腐殖酸的去除能力.  相似文献   
134.
Problems related with industrials effluents can be divided in two parts: (1) their toxicity associated to their chemical content which should be removed before discharging the wastewater into the receptor media; (2) and the second part is linked to the difficulties of pollution characterisation and monitoring caused by the complexity of these matrixes. This investigation deals with these two aspects, an electrochemical treatment method of an olive mill wastewater (OMW) under platinized expanded titanium electrodes using a modified Grignard reactor for toxicity removal as well as the exploration of the use of some specific analytical tools to monitor effluent phenolic compounds elimination. The results showed that electrochemical oxidation is able to remove/mitigate the OMW pollution. Indeed, 87% of OMW color was removed and all aromatic compounds were disappeared from the solution by anodic oxidation. Moreover, 55% of the chemical oxygen demand (COD) and the total organic carbon (TOC) were reduced. On the other hand, UV- Visible spectrophotometry, Gaz chromatography/mass spectrometry, cyclic voltammetry and 13 C Nuclear Magnetic Resonance (NMR) showed that the used treatment seems efficaciously to eliminate phenolic compounds from OMW. It was concluded that electrochemical oxidation in a modified Grignard reactor is a promising process for the destruction of all phenolic compounds present in OMW. Among the monitoring analytical tools applied, cyclic voltammetry and 13 C NMR are among the techniques that are introduced for the first time to control the advancement of the OMW treatment and gave a close insight on polyphenols disappearance.  相似文献   
135.
The effects of different outer diameters and surface oxygen contents on the adsorption of heavy metals onto six types of multi-walled carbon nanotubes (MWCNTs) were investigated in an aqueous solution and lead was chosen as a model metal ion. The results indicated that the percentage removal and adsorption capacity of lead remarkably increased with decreasing outer diameter due to larger specific surface area (SSA). The SSA-normalized maximum adsorption capacity (qm /SSA) and SSA-normalized adsorption coefficient (Kd /SSA) were strongly positively correlated with surface oxygen content, implying that lead adsorption onto MWCNTs significantly increases with the rise of oxygen content and decreases with decreasing SSA. The calculated thermodynamic parameters indicated that adsorption of lead on MWCNTs was endothermic and spontaneous. When the oxygen content of MWCNTs increased from 2.0% to 5.9%, the standard free energy (△ G0 ) became more negative, which implied that the oxygenated functional groups increased the adsorption affinity of MWCNTs for lead. Through calculation of enthalpy (△ H0 ), G0 and free energy of adsorption (Ea ), lead adsorption onto MWCNTs was recognized as a chemisorption process. The chemical interaction between lead and the phenolic groups of MWCNTs could be one of the main adsorption mechanisms due to highly positive correlations between the phenolic groups and K d /SSA or q m /SSA.  相似文献   
136.
在三座DN150 mmX1600 mm有机玻璃塔试验装置上,考察了DN15的塑料拉西环、陶瓷拉西环和不锈钢拉西环三种材质填料对催化剂的粘附能力。在催化剂浓度5‰,液相负荷40 L/h,气相负荷80 m3/h的条件下,经过408h的连续运转,结果表明不同材质填料对催化剂的粘附能力均存在饱和状态,粘附在填料上的催化剂不随时间的持续增加而增多。其中,塑料填料对催化剂的粘附能力最强,增重0.125kg;不锈钢填料次之,增重为0.115kg;陶瓷填料最弱,增重为0.055kg。可为相关领域的工业应用提供借鉴和数据支撑。  相似文献   
137.
Reclaimed water was successfully used to recover the dry Chaobai River in Northern China, but groundwater may be polluted. To ensure groundwater protection, it is therefore critical to identify the governing factors of groundwater chemistry. Samples of reclaimed water, river and groundwater were collected monthly at Chaobai River from January to September in 2010. Fifteen water parameters were analyzed. Two kinds of reclaimed water were different in type (Na-Ca-Mg-Cl-HCO3 or Na-Ca-Cl-HCO3 ) and concentration of nitrogen. The ionic concentration and type in river were similar to reclaimed water. Some shallow wells near the river bed had the same type (Na-Ca-Mg-Cl-HCO3 ) and high concentration as reclaimed water, but others were consistent with the deep wells (Ca-Mg-HCO3 ). Using cluster analysis, the 9 months were divided into two periods (dry and wet seasons), and all samples were grouped into several spatial clusters, indicating different controlling mechanisms. Principal component analysis and conventional ionic plots showed that calcium, magnesium and bicarbonate were controlled by water-rock interaction in all deep and some shallow wells. This included the dissolution of calcite and carbonate weathering. Sodium, potassium, chloride and sulfate in river and some shallow wells recharged by river were governed by evaporation crystallization and mixing of reclaimed water. But groundwater chemistry was not controlled by precipitation. During the infiltration of reclaimed water, cation exchange took place between (sodium, potassium) and (calcium, magnesium). Nitrification and denitrification both happened in most shallow groundwater, but only denitrification in deep groundwater.  相似文献   
138.
“一事不再罚”是行政处罚的基本原则之一,在我国,“一事不再罚”原则在《行政处罚法》中有集中体现.本文从我国一事不再罚原则的概念和含义出发,结合环保工作实际,从一事不再罚原则在环保行政处罚中的具体应用方面进行探讨.  相似文献   
139.
随着人口的增长和人们生活城市生活垃圾产量的增长,成分日趋复杂,危害也日益显露和突出,这种危害不是单方面的因素,而是全方面的因素所引起的,如生活水平质量的提高,消费观的改变,人们总体环保意识的欠缺等等,本文通过分析我国城市垃圾处理现状,提出一些切实可行的方法,一起规范和提高我国垃圾处理水平。  相似文献   
140.
人与自然的关系,一直是人类关注的焦点。人类对于自身在自然界的地位以及二者之间关系的认识经历了漫长而曲折的过程。大家都非常重视人与自然的和谐相处。随着生产力的发展,人类对自然的征服力量越来越强,但人类从未停止对自然界的保护。党的十六届四中全会提出的构建社会主义和谐社会,不仅对人与人、人与社会的和谐提出了要求,还包括人与自然的和谐共处。显然,人与自然的和谐已成为构建和谐社会的有机组成部分。  相似文献   
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