EFFECT OF OXYGEN-PRESSURE ON BEATING TIME IN THE LIME-SODA-OXYGEN PULPING PROCESS

Subject Beating of oxygen added lime-soda pulps laboratory test result s showed that added oxygen to the pulping processes decreased beating time of unbleached pulps. Material and methods The wheat straw (Tritic um aestivum L.) used for these experiments was collected from Central Anotolia in Turkey. The air-dried wheat straw samples were cut to a le ngth of 8-10 cm. Pulping: was performed in a 15 liter electrically hea ted rotary digester. On the complication of each cook, the cooked mate rials were fiberized in a disintergrator and the pulp was washed with cold water. The remaining uncooked material was removed with the aid o f a 0.15 mm slitted screener. Screened pulps were beaten in a Valley b eater to 50 degrees SR levels at 1.5% consistency. Results Some result s are given in Table 1. [GRAPHICS] Conclusion In the lime-soda-oxygen chemical pulping process of wheat straw, changing the oxygen pressure from 0 to 10 kg/cm(2) decreases beating time from the first degrees SR to 50 degrees SR by about 30-50% In addition, experimental inve stiga tions show that adding oxygen to the lime-soda pulping process increas es the first degrees SR values of pulps by about 6-10 units.