Soundproofing of a cement factory in Austria

Situation

Hatschek Rohrdorfer is a traditional regional company in that produces cement of different qualities for various applications.

A calcium mixture is successively heated in a thermal immersion belt so that it can then be used in cement production. The 70-meter-high cyclone in which this heating takes place has 5 large openings through which maintenance is carried out and through which the heat is also discharged to the outside.

Problem

However, these openings also allow the sound produced in the heat exchanger to escape to the outside. These 5 openings are about 6 meters wide and between 5 and 8 meters high. The sound that gets out here is a thorn in the side of the residents. The management of Hatschek Rohrdorfer would like to have a good understanding of the residents and would like to significantly reduce the noise level that the residents receive.

Approach

In a project together with a building physics office, a solution for enclosing the 5 openings was designed. The covers are made with galvanized steel panels that are perforated on the inside to absorb sound. Sliding soundproof doors have been fitted to 3 of the 5 openings to allow forklift access. That would not have been possible with revolving doors

Special challenge

The installation of this solution required the use of a team of alpinists, who rappelled down from the heat exchanger tower to install the top cover in order to fasten the fasteners for the structure.

Result

After an assembly time of 8 working days, the openings were successfully enclosed and the noise level reductions were achieved.