FIELD: chemistry.
SUBSTANCE: invention relates to chemical industry, specifically to recovery of extraction water in production of polyamide-6 by hydrolytic polymerisation of caprolactam. Method comprises collecting extraction water and cooling to temperature of 6÷10 °C to form a suspension of oligomers. Suspension of oligomers is filtered. Obtained oligomers are dried to finished commercial product. Filtrate is evaporated at temperature 25±0.5 °C and residual pressure 66 Pa to required concentration and delivered for polymerisation. Water is used for extraction of equilibrium granulate of polyamide-6.
EFFECT: invention reduces power consumption and consumption of caprolactam, increases output of caprolactam, recovers oligomers in form of a commercial product.
1 cl, 2 dwg, 2 tbl, 6 ex
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