Development of Super-silent Liquid Nitrogen Plant

摘要

A super-silent liquid nitrogen plant has been successfully developed. The noise level of the plant is reduced by 25 dB in comparison with that of conventional plant. The principal sound sources and sound propagation paths were investigated by means of an actual plant under construction. The structure borne noise of cold box and piping supports caused by pressure reducing valves and expansion turbines was found to be extremely great. This paper outlines various noise reduction methods taken to achieve the desired noise level and presents the measured noise reduction effects of each method.