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141.
通过对几种含油污泥无害化处理技术的比选,分析不同处理技术物耗、能耗情况,优选出经济有效的含油污泥焚烧技术,结合新疆油田含油污泥的特点,采用层燃螺旋炉排焚烧技术,利用其燃烧热能生产蒸汽用于原油生产,采用余热吸收急冷与碱液半干法除酸技术,有效控制了二次污染;采用布袋除尘与烟尘固化技术确保了烟气达标排放。年节省成本支出3095.88万元。  相似文献   
142.
油田作业废水处理技术研究进展   总被引:3,自引:2,他引:1  
文章讨论了作业废水的组成与特点,并对近年来钻井废水处理工艺,酸化废水处理工艺,压裂废水处理工艺进行了总结与评述。根据作业废水的处理现状,对未来作业废水的处理技术进行了展望。油田废水处理主要向以下三个方面发展:开发新型处理药剂;建立高效处理工艺流程;从污水源头开始控制。  相似文献   
143.
运用Gambit软件建立了污泥好氧发酵堆体的多孔介质模型,通过自行设计的实验装置获得了堆体的通风粘性阻力系数和惯性阻力系数以及功能膜压差与透气量之间的关系,用Fluent软件分析了堆体不同截面形状及底部通风管数量对堆体通风均匀性的影响,为确定合理的通风管数量及截面几何形状提供理论依据。对上海奉贤区城镇污水厂污泥处理工程发酵仓进行堆体流场模拟,确定堆体采用小拱形截面形状,堆高2 m,宽8 m,底部设置4条通风管,实际运行效果良好。  相似文献   
144.
以磷石膏为原料,二水合硫酸钙、硫酸镁、甘油为添加剂,采用水热法合成硫酸钙晶须,考察了料浆含量、反应温度、反应时间、体系pH等因素对晶须的直径和长径比的影响;并采用SEM技术观察硫酸钙晶须的形貌。实验结果表明,当磷石膏含量2.5%(w)、反应温度130 ℃、反应时间4 h、体系pH 4时,制备得到的硫酸钙晶须长径比为56.24,平均直径为0.17 μm。SEM表征结果显示,硫酸钙晶须形貌规整、分散均匀、直径较小,达百纳米级。  相似文献   
145.
Manganese (Mn) is an essential mineral nutrient in mammals. The physiological role of Mn in animal models is well documented, but little is known about the adverse effects of Mn deficiency or overexposure in humans, including pregnancy outcomes such as birth weight. We examined the relationship of the maternal and cord blood Mn levels with birth weight in a cohort of 172 mother–infant pairs born in Shanghai, China. Non-linear spline and quadratic regression models were used to test the hypothesis of an inverted U-shaped association between the Mn levels and birth weight. The median (range) levels of Mn in the maternal and cord blood were 5.38 (2.34–30.37) μg/dL and 7.66 (2.57–34.23) μg/dL, respectively. An inverted U-shaped relationship was observed between maternal Mn and birth weight after adjusting for potential confounders. The birth weight increased with Mn levels up to 4.18 μg/dL, and a slight reduction in weight was observed at higher levels. The cord blood Mn levels were not found to be associated with birth weight. Both lower and higher Mn exposures are associated with lower birth weight, which may influence important developmental parameters; the association of higher Mn levels with lower weight was weak and imprecise.  相似文献   
146.
玉米秸秆活性炭的制备及其吸附动力学研究   总被引:2,自引:0,他引:2  
以玉米秸秆为原材料,采用ZnCl2活化法制备玉米秸秆活性炭,吸附次甲基蓝染料废水,进行动力学分析。本实验用Langmuir和Freundlich模型对吸附等温线进行拟合,结果表明,玉米秸秆活性炭对次甲基蓝的吸附与Langmuir方程拟合良好,R2=0.9857。采用Lagergren准一级速率模型、Lagergren准二级速率模型、Bangham动力学方程和Elovich动力学方程分别对秸秆活性炭吸附次甲基蓝溶液进行吸附动力学拟合,通过分析得出吸附过程与Lagergren准二级速率模型拟合最好,R2=0.9979。秸秆活性炭对次甲基蓝的最大吸附量达到909.09 mg/g,具有很高的吸附能力。  相似文献   
147.
镍渣的重金属浸出特性   总被引:3,自引:0,他引:3  
在分析镍渣的矿物相组成和重金属元素含量的基础上,鉴定了镍渣样品的浸出毒性,并考察了pH、液固比和浸出时间等条件对镍渣样中铬、铅、铜和锌等重金属浸出特性的影响。结果表明,镍渣中的重金属总量约为渣样的0.9%,且铬、铜和锌的含量较高,需进行安全管理。实验所用镍渣样品为第Ⅰ类一般工业固体废物。在强酸条件下镍渣中重金属浸出浓度较大,pH3后浸出浓度显著降低;液固比40 L/kg时,镍渣中重金属不断溶出,液固比40 L/kg后,浸出达到饱和,浸出浓度趋于平衡;随着浸出时间的增加,重金属离子的浸出浓度先增加后减少,但由于各重金属性质不同,各重金属达到最大浸出浓度的时间不同。  相似文献   
148.
Deterioration of the general ecosystem and specifically quality of the water in Tai Lake (Ch: Taihu), the third largest freshwater in China, is of great concern. However, knowledge on status and trends of dioxin-like compounds in Tai Lake was limited. This study investigated AhR-mediated potency and quantified potential aryl hydrocarbon receptor (AhR) agonists in sediments from four regions (Meiliang Bay, Zhushan Lake, Lake Center, Corner of Zhushan Lake, and Meiliang Bay) of Tai Lake by use of the in vitro H4IIE-luc, cell-based, transactivation, reporter gene assay, and instrumental analysis. Concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (Bio-TEQs) in sediments ranged from less than the limit of detection to 114.5 pg/g, dry weight, which indicated that organic extracts of sediments exhibited significant AhR-mediated potencies. Results of the potency balance analysis demonstrated that acid-labile, dioxin-like compounds represented a greater proportion of concentrations of Bio-TEQs in sediments from Tai Lake. Concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents calculated as the sum of the product of concentrations of individual congeners and their respective relative potencies (Chem-TEQs) based on polycyclic aromatic hydrocarbons and/or polychlorinated biphenyls represented no more than 10 % of the total concentrations of Bio-TEQs.  相似文献   
149.
The antibiotics have attracted global attentions for their impact on aquatic ecosystem. The knowledge about the fate of antibiotics encountering extracellular polymeric substances (EPS) is, however, limited. In this study, we investigated the interacting mechanisms of tetracycline (TC) to EPS extracted from aerobic activated sludge. The contributions of the main components of EPS, extracellular proteins, and polysaccharides were evaluated using bovine serum albumin and alginate sodium, respectively. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and nuclear magnetic resonance indicated that hydroxyl, carboxyl, and amino groups were the domain chemical groups involved in the interaction between TC and EPS, and the binding of TC onto EPS changed the structure of these chemical groups, thus causing shifts in their UV–visible absorption spectra. In addition, we found that extracellular proteins, rather than polysaccharides, were the major active contents involved in the interaction. Three-dimensional excitation–emission matrix fluorescence spectroscopy showed that the fluorophores in EPS were clearly quenched by TC and the static quenching process was observed, implying the complex formation of TC and EPS. Furthermore, thermodynamic analysis indicated that the binding of TC with EPS is spontaneous and dominated by electrostatic forces.  相似文献   
150.
Abstract

This paper introduces a new allocation method on discharge loading of each function zone in a total emission control region. The wind frequency, the position of each district, and the pollutant’s influence area were taken into account in this new method. The concept of “average downwind distance” was brought forward in this paper. The method here is more reasonable than the original method of area distribution, which was proposed by the “A-value” method in regulation of total emissions in China, by means of the simulation of annual average concentration in the total emission control region.  相似文献   
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