PROCESS FOR CONTROLLING THE SUPPLY OF LIQUID IN CONTINUOUSLY WASHING SUSPENSIONS

摘要

PROCESS FOR CONTROLLING THE SUPPLY OF LIQUID IN CONTINUOUSLY WASHING SUSPENSIONS A process is provided for controlling the supply of aqueous suspending liquid in continuously washing fibrous suspensions in aqueous suspending liquors containing dissolved impurities, to remove such impurities by exchanging aqueous suspending liquors substantially free from such impurities for the aqueous suspending liquor, which comprises washing fibrous material of the suspension in aqueous suspending liquid substantially free from dissolved impurities; and forming a washed fibrous suspension in such liquid; withdrawing aqueous suspending liquor containing dissolved impurities; diluting the washed fibrous suspension by adding aqueous suspending liquid substantially free from dissolved impurities; measuring the amount of dissolved impurities remaining with the fibrous suspension after the washing has been completed by determining (1) the volumetric flow rate of the washed suspension; (2) the liquid content of the washed suspension; and (3) the content of dissolved impurities in the suspending liquid; and then controlling the volume amount of wash liquid added according to the washing losses to maintain washing losses within a predetermined limiting range.