The company K+S AG operate the rock- and vacuum salt production site at Bernburg, Germany. At this location, the rock salt is extracted in an underground mining process and processed on the surface processing plant. All products have to fulfil certain qualifications. Beside the chemical composition, the particle size distribution is the most important characteristic. In other words, the fines content (k -160 µm) is limited to 3.5 % (The ROM has an ave. fines content of 5.1 %). At the end of the process the fines and tailings are disposed of as backfill to the underground mine and caverns. Caused by the technical process, larger particles are disposed of to the tailings as well. In this work, the main objective is reducing the tailings amount and increasing the process recovery. For instance, it contains the evaluation of the main and supplementary process steps as well as results of external trial runs at the pilot plants of machine suppliers. In the evaluation, it was found that the air separator and fluidized bed classifier are the main responsible processing steps for the tailings quantity. There are several verified capabilities to improve the recovery. While the external trial runs went well with feed product from the air separator, there are no positive results for processing the tailings material. The hygroscopic character and subsequently elevated water content impedes the production of saleable material. The best results for the air separator feed material were achieved by screening. Besides the capabilities to improve the process in the plant, the products are degraded in terms of fines in several additional places. The reclaimers in the stocks, as well as the drops at the transfer points between conveyor belts, increase the fines content by rough handling.