The filtrate cakes that are thin and fragile are usually the end products of this discharge lie. The materials are capable of changing phases, from solid to liquid, due to instability and disturbance. Two rollers guide the strings back to drum surface and at the same time separation of the filtrate cake occurs as they pass the rollers. Application of the string discharge can be seen at the pharmaceutical and starch industries. String discharge is used if the high solid concentration slurry is used or if the slurry is easy to filter to produce cake formation or if the discharged solid is fibrous, stringy or pulpy or if a longer wear resistance is desired for the separation of the mentioned slurry.