Patent ID: 8449717

Claim:
A method for preventing clogging in a strainer construction for a continuous digester, comprising: providing a withdrawal strainer disposed inside the digester, a withdrawal compartment disposed between the withdrawal strainer and an outer wall of the digester, and an outlet tap in fluid communication with the withdrawal compartment, the withdrawal strainer withdrawing a cooking fluid from a column of pulp in the digester, collecting the cooking fluid in the withdrawal compartment disposed inside the outer wall of the digester, the outlet tap withdrawing the cooking fluid, an evacuation line, in fluid communication with the outlet tap, transferring the cooking fluid away from the outlet tap, adding an additive directly to the withdrawal compartment, and the additive counteracting a precipitation processes in the withdrawal compartment while withdrawing the cooking fluid and the added additive from the withdrawal compartment; wherein the additive is added to a second subsidiary flow of a total flow that is withdrawn from the outlet tap, the second subsidiary flow is returned directly to the withdrawal compartment, and the second subsidiary flow is less than or equal to the total flow; and wherein the total flow is withdrawn from one end of the withdrawal compartment, and the additive is introduced into a second end of the withdrawal compartment.