The MIKRO-GREY project aims to develop an innovative series of filters that fulfil a dual function. On the one hand, they are intended to collect the microplastics from the grey water so that it can be disposed of properly and does not enter the aquatic environment. On the other hand, by separating non-biodegradable COD, the washing machine effluent water is to be made accessible for grey water use. No dirt should be allowed to enter the overflow, but should remain in the filter system. The new filter is also intended to separate dirt from the water in other applications. For use in industrial laundries, for example, a process kit is being developed that will enable quick and easy integration into existing wastewater processes.