The Fibria Pulp and Paper Mill in Jacarei is increasing ozone production to 750 kg/h or 18 tons per day. This is one of the largest ozone installations in the world. Bleaching pulp with ozone is more environmentally friendly than alternative bleaching systems. Ozone is also a very powerful and effective bleaching agent.
Ozone is a very powerful oxidizing agent and the biggest challenge in using it to bleach wood pulp is to get sufficient selectivity so that the desirable cellulose is not degraded. Ozone reacts with the carbon carbon double bonds in lignin, including those within aromatic rings. In the 1990s ozone was touted as good reagent to allow pulp to be bleached without any chlorine-containing chemicals (totally chlorine-free, TCF). The emphasis has changed and ozone is seen as an adjunct to chlorine dioxide in bleaching sequences not using any elemental chlorine (elemental chlorine-free, ECF). Over twenty-five pulp mills worldwide have installed equipment to generate and use ozone.
The ozone system budget for teh Fibria mill is valued at $9,200,000 dollars. The mill has a production capacity of 1.1 million tons of bleached pulp. The additional ozone will allow the plant to increase pulp output by 15%. The mill processes 3,600 tons per day of eucalyptus pulp which feed two separate prdiction lines.
Ozone use spans a wide range of applications, pulp bleaching being one where very large scale generators are used.