Method of fragmenting and/or weakening material by means of high voltage discharges

The invention concerns a method of fragmenting a material by means of high voltage discharges. The material that is to be fragmented is fed through a process zone which is arranged between two electrodes which is flooded with a process liquid. While feeding the material through the process zone, high voltage discharges are generated between the electrodes, for fragmenting the material, and process liquid is fed into the process zone and is discharged from the process zone. In that state, a degree of turbidity of the process liquid discharged from the process zone is determined and is compared with a reference value. In case a deviation from the reference value is detected, one or more parameters of the generation of high voltage discharges and/or of the feeding of the material through the process zone are changed in the manner that, when after the changing of the parameters the determination of the degree of turbidity and the comparing with the reference value is repeated, the deviation which is detected then