摘要 |
<p>The invention relates to a method for use in continuous digestion of finely-divided cellulose-containing material, such as wood chips. According to the invention said finely-divided material is fed in a liquid-filled treatment vessel as a continuous chip pillar through a feeding zone, a heating and impregnation zone, a digesting zone, and a washing zone, the temperature in the heating and impregnation zone being kept lower than in the digesting zone. In order to obtain stable temperature and chemical profiles in these zones the liquor fed in with the chips is caused to flow through the chip pillar in the feeding zone in the direction of feed of the chips with such velocity before said liquor is withdrawn that said chip pillar is fed through the subsequent impregnation zone, where a flow of impregnation liquor in counter-current to the advancing chip pillar is so regulated that the heat-capacity flow of said impregnation liquor is at least equal to the heat-capacity flow of the advancing chip pillar.</p> |