A nonionic surfactant, i.e. alkylene oxide adducts of alkylphenois or higher aliphatic alcohols or acids, in combination with 2) a water soluble low molecular weight organic polyelectrolyte like polyacrylates, and preferable 3) a solvent like tetrahydrofurfuryl alcohol and ethoxylated derivatives thereof, are used to wash pulps of virgin cellulose fibres to remove and recover spent cooking chemicals and pitch.
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