Noise reduction during mining excavations for potash extraction

The problem of noise generated during mining works consists of noise emitted from inside the canal and outside the canal. Interior noise is generated by mining machinery and equipment for coal mining and transportation. Outside noise is generated by the main fans, which must assure a constant, high dedusting efficiency. During this commission, we dealt with lute fans, which were responsible for the emission of noise outside.

The client asked us to propose a noise reduction strategy for the external fans running continuously during potash extraction in the 37 km tunnel. The shaft tower was located 100m below the ground, from which two 1500m deep shafts for the extraction of the polyhalite base were extended. Our task was to silence the lute fans designed to remove dust from the air flowing through them, located at the mine shafts. Due to the large dimensions of the devices, it was necessary to propose a non-standard solution while maintaining the highest acoustic efficiency.

Taking into account the unusual working conditions, care for the mechanical strength of the system, a small space for the silencer and transport possibilities, we had to design a non-standard container silencer with a baffle silencer to increase the acoustic efficiency of the system.

After the acoustic analysis, when materials were selected, it was proposed that we should enclose the noise source in a solid, steel housing with absorbing and reflecting panels. A preliminary concept with overall dimensions, land development and materials used was designed. After the concept got accepted, we produced 16 different container silencers, used in various configurations. We delivered everything to our client’s test zone, where appropriate fans were attached and acoustic tests were performed.

The acoustic efficiency of this design ranged from 28 to 32dBA depending on the selected silencer and fan.

The working team consisted of 1 constructor, 1 junior and 1 senior specialist in acoustics. Tools and technologies used in the project are SketchUp, Autodesk Inventor and AutoCAD.