The goods are flushed into the conical container via a pipeline. An integrated impeller generates a circular movement of the water flow. The product circulates through 180° inside the container and is rinsed out via the flushing channel and fed to the drum washing machine for processing. Stones and earth lumps are heavier than the goods. They sink downwards, are discharged via the pipeline and transported away via a discharge belt with rubber stud belt. Sand and small dirt particles are rinsed out at regular intervals by opening the sludge slide. The washed-out process water is replaced by treated fresh water.