Analysis for a safer design of high pressure oxygen pressure reducing stations in steel plants.

A pressure reducing station (PRS) in a steel plant controls the pressure and flow of high pressure oxygen from a cryogenic air separation plant. Metallic components in PRS are vulnerable to fire in pure oxygen environment. Particles accumulated in filters are the most visible sources of ignition. However, in many fire incidents, the actual source of ignition is found to lie a few meters upstream of filter. It is hypothesized here that particles charged with static electricity accumulate inside pipe and hit the pipe wall in all directions when the flow suddenly increases due to some operational reasons. The resultant kinetic energy can ignite the particle. Theoretical confirmation of this possibility may facilitate laboratory experiments and design changes in system configuration that may finally prevent fire in a PRS. Computational fluid dynamics (CFD) analysis is used to verify the possibility of particle accumulation upstream of the filter.