Plant Werra – Our biggest potash plant

Impressive shaft towers and mine cars at all entrances to the Werra valley indicate that mining has shaped the entire region and continues to do so. The area of the mine underground is similar in size to the city of Munich with suburbs. The integrated facility is the largest site of K+S Minerals and Agriculture with an annual output of about 20 million tonnes of crude salt.

The products manufactured from crude salt mined underground are delivered to numerous countries worldwide. In addition to fertilizers, preliminary products for various technical and industrial applications as well as for the pharmaceutical, food and feed industries are manufactured here.

Partner in the region

Plant Werra employs almost 4,400 people (including the central technology craftsmen at the site and 300 trainees), almost half of whom work underground. This makes it an important employer and training company between Bad Hersfeld and Eisenach. 85% of the employees come from the Wartburg district and the district of Hersfeld-Rotenburg. In addition, the plant is an important client for the local mid-sized economy and a major taxpayer for the local communities. This makes it a central building block for the development of the East Hesse/South Thuringia region.

The Merkers Adventure Mine attracts more than 70,000 visitors to the region every year and around 3,000 visitors a year take part in guided tours of the Werra Caliber Mining Museum on Monte Kali. In addition, the Werra plant is active as a sponsor - mainly in the promotion of youth sports.

The safest place for highly contaminated waste that cannot be recovered is at our two two underground waste disposal sites at Herfa-Neurode and Zielitz. Herfa-Neurode, the first underground waste disposal site of its kind in the world, was opened in 1972. With almost 50 years of experience, we are now able to dispose of a wide range of hazardous wastes from various industries. 

In the abandoned mine fields of our potash mines, we optimally utilize the geological conditions for permanently and safely disposing of your waste at depths of 500 to 800 meters. Far below the groundwater level, sealed gas-tight by salt rock up to 300 meters thick and additionally insulated by further water-blocking layers, people and the environment are safe from this waste, now and in the future. In Herfa-Neurode, both packaged and bulk delivery in silos of waste is possible. 

Many mineral substances can be recovered underground. We place this waste in the cavities once created during the extraction of potash and rock salt, where raw materials are no longer mined. We support the pillars between the mining chambers and therefore not only use the waste as a resource, but also ensure mining safety at the same time. In around 25 years of underground recovery, we have developed numerous proprietary processes for utilizing the material properties of less contaminated waste, and are constantly working on new processes as well as techniques for recovering even more waste. 

At the Wintershall site, pneumatically conveyable waste is transferred to standing silos and then filled into big bags. The contents of the big bags are mechanically compacted on a vibrating plate. It is also possible to deliver materials already packed in big bags, provided they meet the recovery requirements. The big bags are placed underground in a backfilling process. Finally, the remaining cavities are filled with moist salt. In this way, the connection to the pillars is achieved. 

At the Hattorf site, pneumatically conveyable waste is transferred to standing silos and processed into products in a mixing plant according to specific recipes. After being filled into big bags, they harden. Waste already delivered in big bags is stored directly if suitable. The big bags are placed underground in a backfilling process. Remaining cavities are filled with moist salt. In this way, the connection to the pillars is achieved. 

At the Unterbreizbach site, pneumatically conveyable material is initially transferred to standing silos and transported underground via closed pipeline systems. With the addition of liquids (salt solution), a slurry of thick material is formed which is pumped into cavities. There it hardens with complete setting of the liquid and acts as a support for the salt rock.