PROCESS FOR PRODUCING POLYARYLENE SULFIDE AND DEVICE FOR PRODUCING SAME

A production process of a poly(arylene sulfide) (PAS), including a polymerization step of forming a PAS from a sulfur source that is an alkali metal (hydro)sulfides and a dihalo-aromatic compound in an organic amide solvent; a separation step of PAS particles; a countercurrent washing step that is a step of washing the PAS particles with water and/or an organic solvent, wherein a downward current of a PAS particle-containing aqueous slurry is continuously brought into countercurrent contact with an upward current of a washing liquid; a PAS particle re-separation step of capturing a washing waste liquid by a PAS particle re-separating unit, in which a micro-slit filter has been installed, and then re-separating the PAS particles from the micro-slit filter, preferably using a backwashing unit, to discharge them; and a collecting step of the PAS particles discharged, and a production apparatus of a poly(arylene sulfide).