The purpose of de-inking system is to remove the printing inks and stickies that might affect the paper making process. In a de-inking system, ink is detached from fiber. Flotation technology used in de-inking system provides high yield of fibers and simple handling with maximum operating reliability.
The JMC de- inking system consists of number of cells in series with elliptical cross section and with a baffle extending over the entire length to separate suspension chamber from the foam collecting chamber. Air (at the atmospheric pressure) and pulp stock is introduced into the cell through injectors. Flow through nozzles generates vacuum causing micro turbulence of bubble sizes enabling efficient removal of ink particles. This enhances the brightness and reduces dirt specks and stickies. The injectors optimize the quantity of air injected and the size of bubbles generated.
The pulp stock freed ink is pumped from the bottom of one cell to the next cell. The ink laden foam overflows to the foam chamber with the help of motorized paddle. Flotation process is operated in a continuous mode and helps to remove ink particles efficiently in de-inking system. Since the cells in de-inking system are interconnected, level is controlled through level transmitter.
The primary floatation stage in de-inking system ensures highest possible stock purity and the secondary stage optimizes yield. A de-aerator cyclone removes air from the stock and usable fibers are recovered from the foam.