Stenco designed and carried out a biological purification with membranes (MBR) pilot in an industrial laundry with high discharges of COD, SS and anionic detergents for discharges to public channel, due to the characteristics of the spill since the client did not have enough space to implement other available purification technologies. After 3 weeks of operation of the Pilot Plant in the client’s own facilities and the results obtained, it was concluded that with the MBR membrane technology the necessary results required by the Hydraulic Administration could be obtained.