Refinery hydrocarbon gases: Resources and utilization

As part of its noise abatement program, the Standard Oil Company of California has undertaken to reduce the noise radiated from the flare stacks serving the new process plants at the El Segundo Refinery. These flares, used to burn excess refinery hydrocarbon gases, have to operate smokelessly. To accomplish this, high-pressure steam jets are used to discharge a turbulent steam-air mixture into the combustion zone. This system, although muffled, proved to be an intolerable source of noise in the adjacent community. An examination of the noise spectrum indicated that the mixing between the steam ejected from the 34-in.-diam primary nozzle and the ambient air was a major source of noise. A series of exploratory model scale tests were conducted in an effort to reduce the noise. By replacing a single 34-in.-diam nozzle with a multiple nozzle, the radiated noise was reduced by 16 dB. The multiple nozzle configuration and the experimental program leading to its design are described.