The Minamata Convention, which was published in 2013 and entered into force under international law in August 2017, is the starting point for numerous efforts to reduce global anthropogenic mercury emissions. The related Global Mercury Assessment, which was updated in 2018, shows that the cement industry - after artisanal gold mining and energy generation from coal - emits the third largest amount of mercury worldwide. In alignment with the aspiration of w&p Zement GmbH to develop the Wietersdorf site into one of the lowest emission cement plants worldwide, a clear focus was placed on the topic of mercury - also due to the Minamata Convention. The reduction of mercury emissions should, however, be achieved without the mercury being carried over into other material flows, such as products, without a temporal equalisation of emission peaks and with the smallest possible ecological footprint. After extensive research and numerous discussions, it was not possible to find a satisfactory solution for the Wietersdorf site that was already available on the market. For this reason, a project consortium - consisting of ATEC Production & Services GmbH, Scheuch GmbH and w&p Zement GmbH - was formed with the aim of developing a state-of-the-art plant for the separation of mercury from the cement clinker manufacturing process. Within the scope of the research activities, which lasted several years, the mercury cycle and its most important influencing parameters were investigated using the example of the clinker production in Wietersdorf. Based on the data obtained, a pilot plant for the separation of mercury suitable for research purposes was developed and constructed at a total cost of approximately €2.9 million and its influence on the cement clinker production process was investigated over a period of 30 months. Numerous tests and further developments of the mercury separation plant have made it possible to remove an average of > 80% of the mercury entering the cement clinker production process via the fuel and raw materials. With regards to the emissions from the cement clinker production process, significant effects on the monthly average mercury value were shown, which could be reduced to a similar extent as the separation rate. With the knowledge gained from the operation of the pilot plant, a system for the separation of mercury from the cement clinker production process was developed, which can be used flexibly in the cement industry and is ready for the market. A second mercury separation plant based on this principle has been in operation in a German cement plant since 2019. The mercury removal system was subsequently patented by the project consortium and is marketed under the brand name "XMercury".