Pyrolysis behavior of tire-derived fuels at different temperatures and heating rates

Pyrolytic product distribution rates and pyrolysis behavior of tire-derived fuels (TDF) were investigated using thermogravimetric analyzer (TGA) techniques. A TGA was designed and built to investigate the behavior and products of pyrolysis of typical TDF specimens. The fundamental knowledge of TGA analysis and principal fuel analysis are applied in this study. Thermogravimetry of the degradation temperature of the TDF confirms the overall decomposition rate of the volatile products during the depolymerization reaction. The principal fuel analysis (proximate and ultimate analysis) of the pyrolytic char products show the correlation of volatilization into the gas and liquid phases and the existence of fixed carbon and other compounds that remain as a solid char. The kinetic parameters were calculated using least square with minimizing sum of error square technique. The results show that the average kinetic parameters of TDF are the activation energy, E = 1322 +/- 244 kJ/mol, a pre-exponential constant of A = 2.06 +/- 3.47 x 10(10) min(-1), and a reaction order n = 1.62 +/- 0.31. The model-predicted rate equations agree with the experimental data. The overall TDF weight conversion represents the carbon weight conversion in the sample.     

连续起伏管道投产过程中的气相运移研究*

为应对山区液体管道在投产过程中可能出现的气阻、超压问题,从气相运移角度出发,建立液顶气模型,研究在1个U型单元内积气形成、压缩和破碎的全过程,在此基础上,提出连接各个U型单元的气相的传递函数,探讨背压累积因素下,连续起伏管道投产过程中各个U型管段的积气情况和压力的变化,进行动态的建模和计算。以国内某原油管道的现场投产数据与模型结果进行比对。结果表明:可以更加准确地预测山区液体管道投产过程中的气相传递和压力变化过程,能为未来连续起伏大落差液体管道投产的安全稳定运行提供理论指导和技术支持。     

强化风险意识 更新管理理念 全面创建HSE管理体系

介绍了胜利采油厂在HSE管理体系建立过程中重点开展的几项工作,总结了实践中的几点体会,并对下一步体系的运行和持续改进做出了规划。     

仓库计算机网络系统的防雷管理

通过雷电危害及侵入途径的分析,根据仓库建设网络建设实际,探讨了仓库计算机网络雷电防护措施。     

浅谈对重大危险源的有效控制

阐述了重大事故、重大危险源的定义,论述了有效控制重大危险源的必要性,并介绍了重大危险源控制系统的组成。在借鉴国外重大危险源控制系统的基础上,结合我国的实际安全生产管理的情况,对我国如何建立一个有效的重大危险源控制系统,分别从企业和政府两个方面提出了几点建议。     

天然沸石的加工技术及其在水处理中的应用

论述了天然沸石的吸附、离子交换和催化性能,介绍了沸石的超细粉碎、选矿提纯、化学增白、改性或改型、人工合成和再生等加工技术．从去除有机污染物、去除氨氮、降低氟含量、去除重金属离子、作污水滤料、消除放射性物质等方面回顾了沸石在水处理中的应用．并对应用前景和未来发展进行了展望。     

Theoretical equation of gas desorption of particle coal under the non-uniform pressure condition and its analytical solution

Based on the second Fick’s law, the theoretical equation of gas desorption of particle coal under the non-uniform pressure condition was developed in this paper. The analytical solution of the theoretical equation and the method of gas desorption quantity of particle coal under non-uniform pressure condition were obtained.     

Effect of spark duration on explosion parameters of methane/air mixtures in closed vessels

The paper outlines an experimental study on influence of the spark duration and the vessel volume on explosion parameters of premixed methane–air mixtures in the closed explosion vessels. The main findings from these experiments are: For the weaker ignition the spark durations in the range from 6.5 μs to 40.6 μs had little impact on explosion parameters for premixed methane–air mixtures in the 5 L vessel or 20 L vessel; For the same ignitions and volume fractions of methane in air the explosion pressures and the flame temperatures in both vessels of 5 L and 20 L were approximately the same, but the rates of pressure rises in both vessels of 5 L and 20 L were different; The explosion indexes obtained from the measured pressure time histories for both vessels of 5 L and 20 L were approximately equal; For the weaker ignition with the fixed spark duration 45 μs the ignition energies in the range from 54 mJ to 430 mJ had little impact on the explosion parameters; For the same ignition and the volume fractions of methane in air, the vessel volumes had a significant impact on the flame temperatures near the vessel wall; The flame temperatures near the vessel wall decreased as the vessel volumes increased.     

Experimental research into effects of obstacle on methane-coal dust hybrid explosion

An experimental system including pressure transducer, data acquisition card, computer and electric spark ignition device was set up to research methane-coal dust hybrid explosions in closed tubes with different types of obstacles inside. Its dynamic response time was less than a millisecond and the test precision was 0.1%. The experimental results show that the obstacles had great effects on the explosion characteristics in the tube. Hollow obstacles linked with inner wall of the tube induced faster pressure rising than installed center blocked solid obstacles. Obstacles with more sharp corner induce more violent explosions. The most dangerous explosion occurred when spacing between obstacles almost equaled the inner diameter of the tube for the same size obstacle.     

Quantitative indicator of homeostatic risk perception in car following

Driving behavior is largely affected by the risk perception of drivers. On the basis of risk homeostasis theory, we regard that drivers may adjust car movement according to the perceived risks fluctuating around a target level. However, the manner by which risk perception is quantified remains unclear. We propose assumptions on the quantitative indicators of risk perception and identify a suitable quantitative indicator of risk perception in car-following process. Three risk indicators are discussed, i.e. time-to-collision (TTC), time headway (TH), and safety margin (SM). Using homeostatic features as bases, we found that SM more suitably quantifies homeostatic risk perception than TTC or TH does. Data collected from video drive recorders installed in taxis operating in Beijing are used to analyze the target risk level of SM (desired SM, or DSM) of professional drivers during the car-following process. The data collected by Ahn et al. (2004) to verify Newell’s model are converted into DSM data to further analyze the target risk level of general drivers. The DSM histogram of professional drivers shows that the standard deviation of the DSM value is 0.115, with a mean value of 0.862 and a total distribution close to the normal distribution. For a general driver, the mean value of DSM is 0.896, which is higher than that of professional drivers. This research may shed lights on the understanding of driving behavior.