PROPYLENE POLYMERIZATION Russian patent published in 2023 - IPC C08F2/01 C08F2/02 C08F10/06 B01J19/24 

FIELD: polymerization of propylene.

SUBSTANCE: method for producing polypropylene is proposed, including polymerization of propylene in a propylene polymerization system under bulk polymerization conditions to produce polypropylene, where a plurality of vertical elbows of a loop suspension reactor are cooled with a refrigerant and the refrigerant is cooled in a heat exchanger located outside the loop suspension reactor to control the temperature difference between the first temperature of the refrigerant, entering the heat exchanger, and the second temperature of the refrigerant leaving the heat exchanger, the ratio of capacity to temperature difference being in the range of about 11:1 to about 20:1 t/h:°C; discharging the polymerization product containing polypropylene from the loop suspension reactor through at least three continuous diverter valves, the at least three continuous diverter valves having an average discharge rate of about 20 to about 30 tons of polypropylene/hour/valve; passing the polymerization product through a plurality of flash line heaters into a separator; and recycling unreacted propylene directly into the loop suspension reactor; moreover, the volumetric productivity for the polymerization stage is more than 0.36 and less than 0.60 tons of polypropylene/h/m³ of the loop suspension reactor. Embodiments of a propylene polymerization system in which this method is carried out are also proposed.

EFFECT: proposed method expands the range of methods for producing polypropylene.

19 cl, 7 dwg, 2 ex