Forecast and Elimination of Explosions of Cylinders with Liquefied Hydrocarbon Gas


B.S. Rachevsky, Cand. Sci. (Eng.), Prof., info@neftegaztop.ru Gubkin Russian State University of Oil and Gas

Annotation:

Main reason of the explosion of gas cylinders with liquefied propane-butane is the violation of the rules for their refueling with liquefied gas.
Dangerous increase in pressure in the cylinder with the liquefied propane-butane can occur if it is overfilled with the liquefied gas. In case of the cylinder overflow, the liquefied gas expands as the temperature rises, creates the overpressure in the cylinder and dangerous stresses in the cylinder wall, which can lead to its destruction.
If there is a sufficient vapor cushion in the cylinder, the expansion of the liquid phase does not cause dangerous stresses in the vessel.
According to the norms the gas cylinders need to be refueled at the specialized enterprises — gas filling stations where they are refueled strictly by weight on special weight equipment. Such refueling of the cylinders is carried out on 85 % of their volume. The remaining 15 % is the so-called buffer zone, designed to expand the liquid phase of gas during temperature rise.
However, recently, many consumers of the liquefied gas refuel their cylinders not at the gas filling stations, but at the gas filling stations where there are no devices for weighing cylinders, and the refueling is carried out from the gas dispensing column. In this case, the cylinders are filled with overflow.
If the gas cylinder is refueled in the cold season with overflow and then introduced into the heated room, then the pressure in it rises relatively quickly to the destructive one, which is clearly seen from the dependencies and calculations given in the article.
More than 20 years ago in Europe, based on many years of experience in the use of the gas cylinders and conducted studies, the system called OPD (Overfilling Prevention Device) was developed — a device preventing overflow of the domestic gas cylinders by means of the float-type shut-off device that contains the safety valve.
In the USA, since 1998, the use of gas cylinders without a shut-off mechanism and a safety shut-off valve has been prohibited at the legislative level.
Use in Russia of the safe gas cylinders equipped with an OPD-type system is extremely necessary as it will eliminate the occurrence of emergencies accompanied by explosions, human casualties and material damage while operating gas cylinders.

References:

1. GOST R 51753—2001. Рigh pressure сylinders of for compressed natural gas used as motor fuel for motor vehicles. General specifications. Available at: http://docs.cntd.ru/document/1200012999 (accessed: May 4, 2018). (In Russ.).
2. RD 03112194-1095—03. Guidelines for the organization of operation of gas-cylinder vehicles operating on compressed natural gas. Available at: http://docs.cntd.ru/document/1200034846 (accessed: May 4, 2018). (In Russ.).
3. Aliyev A.V., Mishchenkova O.V. Mathematical modeling in engineering. Moscow–Izhevsk: Institut kompyuternykh issledovaniy, 2012. 476 p. (In Russ.).
4. Zarubin V.S. Sumulation. Moscow: Izdatelskiy tsentr «Akademiya», 2013. 336 p. (In Russ.).
5. Viktorova V.S., Stepanyants A.S. Models and methods for calculating reliability of the engineering systems. Moscow: Lenand, 2016. 256 p. (In Russ.).
6. Safe handling of cylinders for liquefied petroleum gases (LPG). Problems and solutions. Available at: http://gas-vector.com/wp-content/uploads/2017/08/Prezentatsiya-Moskva-0217-.pdf (accessed: April 12, 2018). (In Russ.).
7. Rachevskiy B.S. Liquefied petroleum gases. Moscow: Neft i gaz, 2009. 640 p. (In Russ.).
8. Staskevich N.L., Vigdorchik D.Ya. Reference book for liquefied petroleum gases. Moscow: Nedra, 1986. 543 p. (In Russ.).

DOI: 10.24000/0409-2961-2018-7-43-46
Year: 2018
Issue num: July
Keywords : liquefied propane-butane gas cylinders emergencies statistics reason of explosions analytical dependencies safe gas cylinder
Authors: