Dispersion characteristics and hazard area prediction of mixed natural gas based on wind tunnel experiments and risk theory
Autor: | Baoquan Xin, Wenyi Dang, Jianliang Yu, Yongzhong Bai, Xingqing Yan |
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Rok vydání: | 2021 |
Předmět: |
021110 strategic
defence & security studies Environmental Engineering Critical distance business.industry General Chemical Engineering 0211 other engineering and technologies Terrain Soil science 02 engineering and technology 010501 environmental sciences Wind direction Computational fluid dynamics 01 natural sciences Wind speed Natural gas Dispersion (optics) Environmental Chemistry Environmental science Safety Risk Reliability and Quality business 0105 earth and related environmental sciences Wind tunnel |
Zdroj: | Process Safety and Environmental Protection. 152:278-290 |
ISSN: | 0957-5820 |
Popis: | As a complex mixture, high-hydrogen-sulfide natural gas has a high risk of poisoning and explosions after leakage. This study combined wind tunnel experiments, computational fluid dynamics (CFD) technology, and risk theory to explore the dispersion characteristics and hazardous area of released mixed natural gas (M-NG) in complex terrain. Based on risk theory, various external safety protection distances under four kinds of risk criteria were predicted. The results indicated that the dispersion process of M-NG in mountainous terrain can be divided into two components: downhill dispersion and cut-slope dispersion. At the same wind speed, the maximum concentrations for different wind directions can differ by a factor of 10. Compared with the results of the wind tunnel tests, the maximum overestimation was 62.9% when simulating the near-field dispersion of M-NG by CFD, while the underestimation was 28.1% for the far-field dispersion. The critical distance was about 1042 m, the dispersion time was 960 s, and the gas concentration was 42 ppm. The wind speed, wind direction, topography, and their interactions have an important impact on the dispersion process and hazard area of M-NG. The study also indicated that in the quantitative risk assessment, more attention should be paid to the toxic hazard of hydrogen sulfide in M-NG rather than the explosion hazard caused by methane. The risk method fully considers the frequency of accidents and the types of protection targets. It can thus be used as a reference for site selection, land use planning, and emergency protection. |
Databáze: | OpenAIRE |
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