STUDY OF FAN GAS JETS AND DIFFUSIVE FAN FLAMES

Основным способом газосброса (дренажа) различных газов из технологического или иного оборудования является сброс через специально оборудованную вертикальную трубу, по которой газ отводится на большую высоту с дожиганием или без него. Подробный анализ преимуществ и недостатков различных способов сброса технологических горючих газов показал, что наиболее эффективными с точки зрения сокращения длины факелов и зон опасных концентраций являются устройства, обеспечивающие сброс газа в виде веерных струй или пламени, формирующихся на выходе из кольцевой щели. Результаты экспериментов по оценке пожароопасных параметров при веерном сбросе в виде струй или пламени таких газов, как водород, метан и пропан, а также их смесей с инертными разбавителями позволили получить аналитические выражения, оценка которых проведена в настоящей работе. The research is devoted to the study of the effectiveness of the method of technological and emergency discharge (drainage) of various gases, including flammable, toxic or other hazardous gaseous media at petrochemical facilities, based on the use of fan gas discharge, the effectiveness of which is shown in this paper. Currently, facilities utilize a method of drainage from process equipment using a vertical pipe that drains gas to a higher elevation with or without afterburning. The disadvantage of this method is the formation of significant sizes of zones with dangerous concentrations of burning torches in the surrounding space. For example, many studies have shown that the flame length during the discharge of hydrogen or methane is 220–250 diameters of the drainage pipe in the turbulent mode of gas discharge. The use of drainage devices of this type for pipes of large diameter (400 mm or more) leads to material costs while ensuring safe conditions for technological drainage. The experimental and analytical data obtained in the work on the size of the flames of such combustible gases as hydrogen, methane, propane, as well as hazardous zones and the size of fan jets of gases found a good generalization by the Froude criterion. This makes it possible to use this analytical generalization in the calculations and creation of fan devices for real technological objects. According to the results of the study, a very important indicator of the effective fan discharge of the tested gases should be noted in comparison with drainage through a cylindrical pipe. The study showed that the fan flames of hydrocarbon gases, similar to hydrogen, turned out to be 4 times smaller than cylindrical ones. For example, reducing the flame size by 2 times is achieved by diluting propane with nitrogen by half. With a similar dilution of propane with freon 13B1, the flame size is reduced by 3 times. As a result of the research, data on the parameters of fan jets and flames of hydrocarbon gases were obtained, allowing them to be recommended during technological operations for the discharge of various gases using drainage devices in the form of annular slits. The relevance of experimental determination of the sizes of fan flames of various hydrocarbon gases, in particular LNG, and obtaining generalizing analytical dependencies for their assessment is due to the expansion of the current scale of their production and application and the requirements to increase the level of fire and environmental safety when handling combustible or other gases. The lack of necessary data in the scientific literature on the parameters of LNG fan flames also indicates the relevance of such studies