TH18184A - "Primary water-separated pulp production process" - Google Patents

Abstract

Process for preparing paper pulp from lignin-containing cellulose material. Revealed This includes a pre-hydrolysis process followed by the hydrolysis of components. Neutralize the cellulose material that has been pre-decomposed with water in the reaction tank with a liquor. Of alkaline neutralization The degradation of the components is carried out with water which is made into Medium out of the reaction tank The lignin is removed from the cellulose material that has been broken down by water. Preliminary neutralized With an alkaline cooking liqueur containing sodium sulfide and sodium hydroxide.

Claims (6)

1.Method for pre-batching of aqueous dispersed kraft pulp with a batch From cellulose materials containing lignin, the following steps are performed: a) Initial aqueous degradation of such materials. In a shortened version of the bets as it makes It forms a cellulose material that has been initially degraded by water. B) neutralization of the aqueous degradation components and the aforementioned cellulose material. In the shredder at a temperature of 140-160 ํ C with a click Of alkaline neutralization (alkaline) which contains sodium hydroxide. And sodium sulphide by At the alkaline addition of the liquor neutralization is 5-25% of active alkaline, calculated as the equivalent of Na2O to dry wood. As resulting in a component obtained by hydrolysis that Neutral and neutral preliminary hydrolysis cellulose material and the residual alkaline content of 1-20 g of yielded NaOH / l c) removal of the components obtained from the neutral aqueous decomposition from And d) remove lignin from a neutral pre-hydrolyzed cellulose material. With alkaline cooking liqueur, sodium sulphide and sodium hydroxide are available. 2. Methods in accordance with claim 1 where such neutralization is performed in the selected 10-40 minutes in 20-30 minutes. 3. Methods in accordance with claim 1 or 2 in which the resulting component The substance with neutral water is removed from the digester. By replacing it with a used cooking click 4. Methods in accordance with claim 3, where a used cooking click is Concentrated, contains residual alkaline of 10-20 g of yielded NaOH / l. And the selected temperature is between 150-180 ํ C 5. Methods consistent with claim 3 or 4, where such neutral material is Take action before removing the lignin to the reaction of the initial operation. In which the click Cooked that was used and reacted such neutral material under alkaline conditions greater than pH 9 chosen at 150-180 ํ C and selected for 10-30 minutes. 6.Methods of treatment consistent with any one of claim 1-5, including removal. Parts of the components obtained by hydrolysis From the aforementioned shredder before the said neutralization step