The invention relates to a
polymerization manufacturing technique and device for
polyamide. The manufacturing technique comprises the steps of feeding molten
caprolactam,
titanium dioxide,
benzoic acid and an additive, dynamically mixing at a high temperature for prepolymerization and postpolymerization, granulating, pre-extracting, extracting and
drying to obtain the final product. The device comprises a melting
system, a feed
system, a high-temperature dynamic mixing
system, prepolymerization and postpolymerization towers, a pre-extraction column, an extraction column, a recycling system and a
drying tower. According to the invention, a high-temperature dynamic
mixing tank is set additionally. The mixing of the raw materials and
hydrolysis for ring opening and
dehydration of
polyamide are performed at a state of dynamically mixing to achieve a more sufficient and stable pre-addition
polymerization and a more uniform and stable
molecular distribution of post-polycondensation. A slice and a water separator of the extraction column are used for mainly extracting oligomers through the pre-extraction column and extracting a
caprolactam monomer through the extraction column with a stable concentration. A slice cooler of the
drying tower is used for cooling the slices rapidly. An extraction water recycling system is used for recycling the oligomers in the pre-extraction water and the
caprolactam monomer in the extraction water.