The filter cake consisting of a mixture of clay, silt and fine sand from the rock of the Rhenish Slate Mountains has now been renamed by Hartsteinwerke Sooneck GmbH to Rheinstein Clay. With this new name, the company wants to highlight its centuries-old tradition on the River Rhine as well as the high quality standard achieved today. The renaming to Rheinstein Clay was needed for technical reasons because clay describes the character of the product better than filter cake. Filter cake is the term used to describe the residue of materials retained in a chamber filter press.
Better compressive strength
Dr Willem Douw, Operations Manager at Hartsteinwerke Sooneck GmbH: “Thanks to its particle size distribution and water content, Rheinstein Clay mixes well with other earths with which bodies are prepared for processing in a blending bed. In the firing process, Rheinstein Clay plays out its biggest advantage: Sintering starts already at low firing temperatures. This gives the fired products better compressive strength.”