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21.
介绍了国家“三废”综合利用方面的政策,结合油田行业资源综合利用现状,提出如何进一步开展油田行业“三废”综合利用工作,并更好地利用国家资源利用税收方面的优惠政策,开拓油田行业“三废”综合利用渠道,推动“三废”综合利用,争取得到最大限度的减免税额。  相似文献   
22.
介绍了国内外加油站油气回收处理技术现状及应用进展,阐明了国内开发的重点应是:密封加油系统及设备、吸收式油气回收装置及分散吸附集中处理系统。  相似文献   
23.
氢化物发生一原子荧光光谱法测定气田废水中的痕量砷   总被引:2,自引:0,他引:2  
采用氢化物发生-原子荧光光谱法测气田废水中的痕量砷。方法有取样量少,操作简单、灵敏度高、准确度高、重现性好等优点。砷的测定线性范围为1~200ng/mL,方法的检出限为0.0453ng/mL,相对标准偏差小于等于1.6%,加标回收率在96.0%~97.7%范围内。测定密码标样与气田废水中的痕量砷,获得了满意的结果。  相似文献   
24.
火炬瓦斯放空问题一直是石化行业的一个重点研究课题。我们经过不断地摸索、探讨,开发了燃气轮机回收火炬瓦斯的技术。采用燃气轮机回收火炬瓦斯,是消灭火炬的手段之一。介绍了燃气轮机的原理、流程及效果,在推广使用方面具有实用性。  相似文献   
25.
井下火花——矿井火灾的点燃源   总被引:1,自引:0,他引:1  
海彦合  袁恒志 《灾害学》1996,11(3):79-83
考察了各类井下火花诱发灾害的典型实例以及80年代以来国内外的研究状况,指出深入开展这一课题的研究对防灾的重要性.  相似文献   
26.
回采工作面瓦斯涌出量预测的神经网络方法   总被引:1,自引:1,他引:1  
回采工作面瓦斯涌出量受煤层瓦斯含量、工作面产量和采煤方法等各种因素的影响 ,笔者通过研究得出 :回采工作面瓦斯涌出量与煤层的赋存条件和开采条件之间是一种非线性关系 ,但目前还难以用精确的数学建模来求解。因此 ,提出了一种应用BP人工神经网络模型和算法 ,建立工作面瓦斯涌出量预测模型 ,从而预测不同开采条件下回采工作面瓦斯涌出量。实际应用表明 ,模型精度能满足要求。笔者还对隐含层神经元数目对步长影响作了讨论。  相似文献   
27.
City hazardous gas monitoring network   总被引:2,自引:0,他引:2  
In our today's societies, many dangerous chemicals are produced and transported. Due to the vast use of chemicals, more chemical accidents are taking place with huge losses. In this study a city hazardous gas monitoring network was designed to detect the dispersion of toxic and combustible gases in the primary stages. The network could cover hazardous chemical facilities, important hazardous chemical routes, warehouses and special locations which may be the targets of terrorist attacks. The network is consisted of several local networks and a central control panel complex. Each local network has a local control panel in the center and many detectors and sounders around it at distances less than 3000 m that communicate with the local control panels wirelessly. In each location there are two types of gas detectors, toxic and combustible, and a sounder which are equipped with a wireless, radio frequency modem allowing the units to communicate readings and other information on a real-time basis with a remotely located local control panel. High sensitive Photo Ionization Detectors, PIDs, are used to provide fast and low-level on-site screening for chemicals contamination. Combustible gas detectors are the second choice to sense the combustible gas and verify the readings of PIDs in this regard. The central panel consists of several connected control panels work uniquely helping a computer set and the appropriate software and communicate with local control panels via telephone lines. All of the network components are shown on the monitor of central panel with special symbols by geographical information system program. The system is fully addressable so that the high level detection of a detector produces a blinking color double-circle around its symbol in GIS plan. In case of high level gas detection, a team of experts who are fully equipped with different portable detectors depart to the site to test the field to identify the chemicals. All readings of detectors are saved in a data bank and then analyzed to find any chemicals spills and leakages. The network was simulated by a special program so that the components of local networks and the central panel are shown in separate windows. By clicking on one detector on environmental window the formerly designed responses will be activated in central panel window.  相似文献   
28.
采用顶空气相色谱法测定食品中甜蜜素含量,探讨了气液相平衡条件及色谱条件的选择,实验结果表明甜蜜素的标准溶液在0.1-0.4μg/l范围内具有良好的线性关系,回收率为87.5%-101.8%,相对标准偏差为2.6%.  相似文献   
29.
On July 31, 2014, at around 23:57, several huge explosions occurred that lasted for 2 h in Kaohsiung City, Taiwan. As a result of a gas leak from a ruptured underground pipeline, the catastrophic incident destroyed more than 6 km of roads, killed 32 people, injured 321 people, and damaged 3259 buildings. Pipeline explosions have been reported as a repeatedly occurring problem, indicating that (1) complex systems are difficult to manage and control, and (2) humans are unable to effectively learn from experiences of accidents. Initial analyses results reveal that root causes of this incident were a combination of a series of complex chain reactions, which eventually led to propylene leakage and explosion. This is a systematic problem, which can hardly be investigated or analyzed by traditional research approaches. Based on the investigation reports and “systems thinking” method, this study develops causal loop diagrams for the Kaohsiung gas explosion to explore the root causes of the disaster. The research results indicate that (1) this pipeline explosion incident was the result of the chain reactions and was the output of a complex system; (2) the mental model of “production first” and “experience gap” were the root causes of the disaster; and (3) to achieve a higher safety standard, continuous education to improve the mental model of “safety first and safety over production” are essential. The findings of this study may contribute toward the improvement of the standard operating procedure for disaster management and preventing similar incidents in the future.  相似文献   
30.
In this study, in order to research the synergistic inhibition effect of nitrogen and ultrafine water mist on gas explosion in a vented duct, a semi-confined transparent chamber was designed with the size of 120 × 120 × 840 mm, and the experiments were carried out with stoichiometric methane/air premixed mixture (fraction of methane: 9.5%), adding different fractions of nitrogen and ultrafine water mist. The experimental results showed the following: The combination of nitrogen and ultrafine water mist had a synergistic inhibiting effect on methane/air explosion, which was preferable to the single use of any kind. With the increase of spraying time of water mist and fraction of nitrogen, the initial shape of the explosion flame became snakelike, and at the same time the peak flame propagation speed and peak overpressure decreased significantly. When the nitrogen fraction was increased to 10% and the mist spraying time was increased to 2min, synergistic inhibiting effect on overpressure was high efficient. However, with the increase of spraying time of water mist and fraction of nitrogen going on, the amount of increase of explosion inhibition efficiency was gradually reduced.  相似文献   
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