多级人工湿地-塘组合系统去除污染物研究

通过多级人工湿地-塘组合系统在不同的水力停留时间下处理污染水体,对各项出水污染物进行测试对比。结果表明:在初春低温条件下,COD,TN和NH₄⁺-N的去除率随着水力停留时间的增加显著提高,在保证处理效果的前提下,水力停留时间选择4 d较为合理。在水力停留时间为4 d时进行为期12个月的试验。试验结果表明:随着季节的变化,多级人工湿地-塘组合系统对模拟农村径流污水的净化效果保持在一个合理的波动范围内,在夏季时对污水中COD,TN以及NH₄⁺-N去除效果比在冬季时好。从试验去除污染物的效果可以看出,本系统可以在除污染物方面达到比较令人满意的效果,COD出水水质最好时为Ⅳ类水质,NH₄⁺-N出水水质最好时接近地表水Ⅳ类水质。     

考虑降解时变扩散系数污染物迁移模型解析解

降解作用是污染物在介质中运移的主要控制进程之一。假设扩散系数为深度的线性函数,建立了污染物在多孔介质中的一维扩散模型,同时考虑降解作用的影响,针对零浓度的下边界条件,推求了模型的解析解。将常扩散系数模型解与相关文献进行了对比,说明了本文所提方法的正确性及可靠性。基于变系数计算模型,讨论了降解作用对污染物运移规律的影响,并分析了相关参数的敏感性。结果表明,扩散系数对计算结果存在较大影响,降解作用能够有效降低污染物的浓度,且降解越强,污染物浓度达到稳定状态需要的时间越短。     

天然气净化厂上游作业过程潜在致泡物质浅析

目的明确溶液中杂质的来源,以判断脱硫溶液的发泡原因。 方法调研钻井、酸化及防腐作业使用的工作流体组成,分析其中潜在的致泡物质。 结果钻井液中的润滑剂、酸化液中的助排剂及集输过程使用的缓蚀剂中均含有表面活性剂类物质,具有强致泡能力。 结论上述物质被高速流动的原料气夹带进入脱硫装置,可导致脱硫溶液发泡。      

燃油锅炉改烧乳化油的可行性分析

分析了目前我国燃油锅炉的使用现状,论述了燃油锅炉改烧乳化油的意义。从探讨乳化油作为锅炉替代燃料的优点出发,在理论和实践两个方面分析了采用乳化油作为锅炉替代燃料的可行性。     

航天器防污染真空试验设备

提出一种专用型航天器防污染真空除气罐,即基于真空烘烤除气及黑体加热技术,实现污染物控制及复杂形状航天器高精度控温.通过试验及气相色谱质谱连用测试仪验证,该真空除气罐可有效控制试验过程中的污染物,且实现了航天器污染控制试验高通用性及自适应性.     

声发射技术在绝缘子污秽放电监测中的应用

通过分析现行绝缘子污秽监测方法的一些弊端,在这个基础上,研究了绝缘子污秽放电存在的声发射现象,提出了一种基于声发射技术监测绝缘子污秽放电的方法。研制了污秽放电监测装置并进行了大量试验。通过分析绝缘子污秽放电过程以及伴随放电出现的声发射现象,揭示出污秽放电的严重程度和声信号之间的关系,证明了通过监测绝缘子污秽放电发出的声信号可以实现对绝缘子污秽的在线监测。     

江西省水污染物总量控制及分配方案

按照保持江西省水质总体良好,局部污染合理控制,兼顾各市、县发展需求,并给下游行政区良好入境水质的思路,提出了一个全省水污染物（点污染源）总量控制及分配方案.方案注重了合理性与实用性相结合,实际应用简单、方便.     

Sulfur behavior in chemical looping combustion with NiO/Al2O3 oxygen carrier

Chemical looping combustion (CLC) is a novel technology where CO₂ is inherently separated during combustion. Due to the existence of sulfur contaminants in the fossil fuels, the gaseous products of sulfur species and the interaction of sulfur contaminants with oxygen carrier are a big concern in the CLC practice. The reactivity of NiO/Al₂O₃ oxygen carrier reduction with a gas mixture of CO/H₂ and H₂S is investigated by means of a thermogravimetric analyzer (TGA) and Fourier Transform Infrared spectrum analyzer in this study. An X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscope (SEM) are used to evaluate the phase characterization of reacted oxygen carrier, and the formation mechanisms of the gaseous products of sulfur species are elucidated in the process of chemical looping combustion with a gaseous fuel containing hydrogen sulfide. The results show that the rate of NiO reduction with H₂S is higher than the one with CO. There are only Ni and Ni₃S₂ phases of nickel species in the fully reduced oxygen carrier, and no evidence for the existence of NiS or NiS₂. The formation of Ni₃S₂ is completely reversible during the process of oxygen carrier redox. A liquid phase sintering on the external surface of reduced oxygen carriers is mainly attributed to the production of the low melting of Ni₃S₂ in the nickel-based oxygen carrier reduction with a gaseous fuel containing H₂S. Due to the sintering of metallic nickel grains on the external surface of the reduced oxygen carrier, further reaction of the oxygen carrier with H₂S is constrained, and there is no increase of the sulfidation index of the reduced oxygen carrier with the cyclical reduction number. Also, a continuous operation with a syngas of carbon monoxide and hydrogen containing H₂S is carried out in a 1 kW_th CLC prototype based on the nickel-based oxygen carrier, and the effect of the fuel reactor temperature on the release of gaseous products of sulfur species is investigated.     

Deactivation of Pt/VC proton exchange membrane fuel cell cathodes by SO2, H2S and COS

Sulfur contaminants in air pose a threat to the successful operation of proton exchange membrane fuel cells (PEMFCs) via poisoning of the Pt-based cathodes. The deactivation behavior of commercial Pt on Vulcan carbon (Pt/VC) membrane electrode assemblies (MEAs) is determined when exposed to 1 ppm (dry) of SO₂, H₂S, or COS in air for 3, 12, and 24 h while held at a constant potential of 0.6 V. All the three sulfur compounds cause the same deactivation behavior in the fuel cell cathodes, and the polarization curves of the poisoned MEAs have the same decrease in performance. Sulfur coverages after multiple exposure times (3, 12, and 24 h) are determined by cyclic voltammetry (CV). As the exposure time to sulfur contaminants increases from 12 to 24 h, the sulfur coverage of the platinum saturates at 0.45. The sulfur is removed from the cathodes and their activity is partially restored both by cyclic voltammetry, as shown by others, and by successive polarization curves. Complete recovery of fuel cell performance is not achieved with either technique, suggesting that sulfur species permanently affect the surface of the catalyst.     

单杂质废水处理网络设计

提出一种用于单杂质废水处理网络设计的新方法.这种方法由1个原则和3个规则构成,其指导思想是全局的最优性通过保证每一步的最优性来实现.新方法以除去单位质量杂质所需的费用作为选择下一个设计步骤的依据,每做出一次选择之后,需对剩余问题做一次更新.这样得到初始分步式网络结构,然后再根据规则对其做进一步的调优.与现有的图形化方法和数学规划法相比,新方法的特点是简单而且有效.