A car assembly plant petrol filling station, finished vehicles at the factory automobile gasoline filling operation, assuming the accident occurred at gasoline filling process, a large gasoline leak to the ground, large-scale diffusion of gasoline evaporation . With the accumulation of time, the concentration of gasoline vapor in the environment will continue to rise, when it comes to static electricity sufficient to ignite gasoline vapors, sparks, heat or electric arc, which will be localized fire or explosion, causing the entire station even shop a series of explosions. Under normal circumstances, there is no static electricity, fire or the like in petrol filling station inside, but the electrical equipment inside the refueling station after a long run will generate a lot of heat, but also because the protective housing or sealing measures are not in place for electrical equipment, electrical within the current environment will be in direct contact with the explosive gas gasoline vapor, causing a fire or explosion.
In accordance with the relevant provisions of the "explosive environment power plant design specifications" (GB 50058) to determine the gasoline filling station gasoline leak for the two sources of release, that during normal operation, is expected to release impossible, if it is only occasionally and release short-term release of the source of release. The situation is such a large area of leak gasoline evaporate proliferation of secondary sources of release, designated as Zone 2 hazardous areas. In reality, for gasoline vapor in the air geometric pision of explosive gas explosion-proof partition are usually rely GB50058 Appendix B explosive atmosphere hazardous areas typical example of the range of explosion-proof partition graph partition. However, the method relies on the experience of such proof partition pision, did not take into account the mechanical ventilation. Ruled out mechanical ventilation factor, often-proof partition area will be pided too large. Combined with business, all the equipment is more difficult to implement EXPLOSION workmanship, investment is too large, it is not conducive to maximizing corporate profits, but also caused unnecessary waste.
This design reduces the concentration of gasoline vapors inside the refueling station by way of the use of mechanical ventilation, and for fueling stations for mechanical ventilation within two working conditions, using varying concentrations finite element analysis software FLUENT evaporation of gasoline vapor diffusion, etc. We conducted a simulation. According to the provisions of GB50058 3.2.5, when explosive gas concentrations below its lower explosive limit of 10% may designate a non-explosion-proof partition, so the design based on the simulation results of finite element analysis software FLUENT designation of a gasoline under mechanical ventilation vapor concentration range of 10% of the limit, electric defined within this range of explosion-proof electrical, and explosion-proof electrical selection. By finite element analysis based on proof partitions delineate the scope of electrical equipment will be significantly less than the national standard for the designation of the range of secondary sources of release proof partitions, you can narrow the scope of the explosion-proof partition is not configured outside the explosion-proof partition having a function by This will avoid unnecessary waste. After adding in the explosive atmosphere mechanical ventilation design, this article will continue to optimize its design fire and explosion on petrol filling stations to transform the refueling station is located on both sides plus two non-combustible material produced by the 1.2 m high protective shield . Since gasoline vapors are heavier than air and 1.2 meters of gasoline vapor barrier may prevent its accumulation in a small area spread to the outside.
Finite element simulation and fire and explosion prevention design results thus showed: gasoline filling station after passage of mechanical ventilation design, build-up inside the petrol station steam greatly reduced for the safe operation of the workshop provided a guarantee. Gasoline vapor concentration using finite element simulation of mechanical ventilation after explosion greatly narrowed the scope of the national standard zoning regulations, to avoid the waste of resources explosion. Join refueling station within the bezel, the gasoline vapor is limited to a small area to prevent its spread, it provides an important guarantee for the safe operation of the entire plant. 某汽车总装车间汽油加注工位防爆电气设计优化(2):http://www.751com.cn/guanli/lunwen_28688.html