| 摘要 |
<p>A method for producing pulp is disclosed. More particularly, the invention concerns a displacement batch cooking process comprising a steam-phase prehydrolysis step, wherein the recovery of the by-products is improved. In the recovery step of the present invention, after the target P-factor in the prehydrolysis stage is reached, hot washing liquid is introduced into the digester from the bottom thereof. The washing liquid is circulated via the suction screens to the top and to the bottom of the digester until the prehydrolyzed chips are under the washing liquid. The hot washing liquid containing by-products is recovered from the digester and the digester contents are neutralized by displacing the washing liquid with alkaline liquor.</p> |
