To prevent a thin plate 1 to be exfoliated from winding around a draining roll 3 and caught by the same in a draining apparatus in which the plate 1 after sprayed with a cleaning solution drains with the aid of a draining roll 3.

A draining apparatus is adapted such that it includes a draining roll where grooves are formed in a draining roll surface while holding a plate to be exfoliated after sprayed with a cleaning solution between upper and lower draining rolls and moving the same. In the apparatus, a speed of each draining roll can be arbitrarily altered. A first pair of upper and lower draining rolls 3a of the draining apparatus 2 are rotated with a motor 15a and is adjustable in its speed with a speed adjusting knob 16a, and a second pair of upper and lower draining rolls 3b are rotated with a motor 15b, and are adjustable in its speed with a speed adjusting knob 116b, and a final pair of upper and lower draining rolls 3c are rotated with a motor 15c, and are adjustable in its speed with a speed adjusting knob 16c.