Venturi

Effective corrosion protection for steel

Venturis are primarily used for gas cleaning and gas cooling.

In metal extraction, for example, they are installed after the roasting processes of metal-bearing ores (copper, zinc, etc.). In this way, solids (dust) contained in the gas are washed out and chemical reactions of components of the gas flow are brought about.

Venturis work in the countercurrent or direct current process. They are usually made of steel. Their construction is complex. The basic construction consists of a cylindrical lower part, the venturi throat and the venturi head with spray nozzle and gas inlet. The entering gases can have a temperature of up to 500 °C.

In view of the aggressive stress, the steel structure must be protected by an acid resistant lining. In order to be able to design a safe protective lining, a sound technical knowledge of the complex stresses and the process-technical mode of operation is required. STEULER-KCH supports you in this case with the corresponding know-how, as we have many years of experience with such projects and can thus rely on technically optimized solutions, especially for detailed designs.

The steel substrate must be permanently protected against three different stress scenarios:

Very hot and dry in the gas inlet
Mixed stress hot and wet in the spray nozzle area
Wet and cool at the bottom

Furthermore, the complex geometric shape of a venturi requires the use of special brick formats and also specially made shaped bricks.

The chemically resistant lining for the steel substrate is usually formed by a pre-vulcanized rubber coating. To ensure that this is not thermally overstressed, a heat transfer calculation must be prepared, especially for the area of the gas inlet. On this basis, a suitable combination of insulation materials and acid resistant lining can then be selected for the specific project.

In wet areas, the focus is on a chemically resistant design of the protective lining. Because of the different types of stresses, different grades of bricks and mortars are usually used in different areas of a venturi.

Depending on the process and spray medium, acid resistant and / or carbon bricks are used. The use of graphite bricks can also be considered if the thermal stress requires it.

STEULER-KCH can offer all the materials required, from sealing to mortars and brick materials, and of course the complete installation. Our expirienced experts have extensive knowledge and a variety of possible lining materials to master the processes.