VERTICAL COUNTERCURRENT SOLID-LIQUID CONTACT METHOD, METHOD FOR WASHING SOLID PARTICLES, METHOD FOR PRODUCING POLYARYLENE SULFIDE, AND DEVICE THEREFOR

摘要

A longitudinal solid-liquid countercurrent contact method and apparatus are provided in which an aqueous slurry containing solid particles is supplied from an upper part and is caused to pass through a plurality of contact-processing chambers connected in a vertical direction while being caused to proceed downward, a contacting liquid is supplied from a lower part and is caused to pass through the plurality of contact-processing chambers connected in the vertical direction while being caused to proceed upward, and the aqueous slurry and the contacting liquid are caused to be continuously subjected to countercurrent contact, wherein the viscosity of a liquid phase in at least one of the contact-processing chambers is controlled, and especially the viscosity · 1 of a liquid phase in a contact-processing chamber positioned at an uppermost part is controlled to fall within a range of 0.9 ‰¤ · 1 /· 0 ‰¤ 2.0 with respect to the reference viscosity · 0 as the viscosity of a predetermined reference composition of a liquid phase at a predetermined temperature.