Valves in action -
Bleeding and venting valve EB 1.12
Bleeding and venting of filters for thermal water in a thermal bath
The brine for the thermal water in many thermal baths is withdrawn from the ground in many different ways. In unprocessed condition it can seldom be used directly for medical purposes. Thus, various types of brine are treated and, in doing so, they pass through a large number of different filter systems. The latter have to be effectively vented.
Using valves in thermal baths places the highest demands on the material to be used. The thermal bath water is tapped at a depth of approximately 770 m. It is heavily mineralised (fluoride-containing sodium chloride thermal water) and, owing to the usually high salt concentration, it is extremely corrosive. In addition, due to the fact that the bleeding/venting valves are installed on top of a pipeline, they come into direct contact alternately with water and atmospheric oxygen, which poses additional requirements on the corrosion resistance of the employed materials.
Given the high temperatures and high mineralisation of the brine, the customer replaced the normally coated bleeding and venting valves with valves from titanium. This material is particularly resistant to external influences because, when getting in contact with oxygen from water or air, the surface of the titanium forms a thin layer of titanium oxide that protects the material. The employed float-controlled bleeding and venting valve EB 1.12 is designed for temperatures up to +80 °C and a flow rate of 12 m³/h at a differential pressure of 2 bar. The body and internal parts of the valve are made from titanium (3.7025 / 3.7035), the clamp is fabricated from stainless steel (1.4404).
