Hydrogen peroxide bleaching is a single-stage or two-stage process. This bleaching agent can be used in extraction stage of the bleaching sequence. However, it is also useful as a terminal stage. When it is used, it can be saved a great amount of ClO2 chemical in the subsequent stage. Some bleaching plant design the system as the first tower is at medium consistency whereas the second tower at high consistency. Ours bleaching plant is two stages and medium consistency system. We used it in extraction stage. At both stages we used 3-4 kg/ton whereas the magnesium sulfate is 1-1.5 kg/ton. At first extraction stage we also used oxygen with it. A two-stage process has an advantage in providing a cleaner pulp. The chemistry is very similar to that involved in oxygen delignification.
Paper pulp bleaching
White paper, such as copy paper, is all around us. Since the bleaching process that uses hydrogen peroxide to bleach paper and pulp instead of chlorine gas was introduced, demand for hydrogen peroxide has soared. Hydrogen peroxide is also used in a number of other applications, including industrial oxidation, cleaning in the semiconductor manufacturing process, and pollution/waste water remediation, etc.