Noise levels from a power station were uncomfortably close to the environmental noise planning conditions, but it was unclear which were the dominant noise sources.
Noise diagnosis
Detailed diagnosis proved that the dominant contribution was high-frequency noise (>500Hz) radiated by the Gas Reception Facility. Vibration measurements were used to calculate the proportion of the noise from the various plant elements so that their contributions could be ranked. The results were used to determine the minimum parts of the plant that would require attenuation in order to meet the noise specification.
This process showed that is was only necessary to treat the reducer, expander and associated valve section of the facility instead of the much larger areas previous considered, saving a considerable sum.
Noise mitigation measures
We provided details of our innovative, high-performance acoustic lagging that was manufactured and installed by Sound Damped Steel. This has an outer skin constructed from highly damped laminated steel, making it very tolerant of installation practicalities. Moreover, we have also developed versions that eliminate the corrosion problems inherent in conventional lagging designs that almost invariable leak, causing hidden corrosion.
The diagnostic process illustrates how costs can be kept to an absolute minimum by precisely ranking noise contributions from different components, even amidst complex arrays of pipework, valves and other sources.
The effect of the treatment was to reduce the noise from this source by 16 -19dB(A), eliminating it as a contributor off-site. Occupational noise levels in the area were also reduced by an average of 8dB(A). More information is available on the Sound Damped Steel installer website here.
