(EN) The present invention relates to a method for optimizing the liquor-to-wood ratio, especially in a pre-impregnation vessel and a continuous digester, when producing chemical pulp. The method is based on a transfer circulation with the aid of which chips are transported from the said pre-impregnation vessel (2) through an input conduit (9) to the said digester (1). The principle is that chips are conveyed from a feeding-out device (5) at the bottom of the pre-impregnation vessel to the top separator (7) of the digester, together with circulation liquor. A part of the liquor is separated off in the said top separator (7) and the remainder in a screen section (8) lower down in the digester, in order subsequently to be returned through a return conduit (11, 12) to the feeding-out device (5) of the pre-impregnation vessel via a pump (4) and a heating device (3). A constituent stream in a conduit (13) is drawn off from the return conduit (11, 12), at a location upstream of the heating device (3), and is conveyed preferably to the upper part of the pre-impregnation vessel (2), so that the liquor-to-wood ratio in the said pre-impregnation vessel can be increased at the same time as the liquor-to-wood ratio in the upper part of the digester (1) can be decreased.
