Method of terminating gas phase polymerization of olefin, method of initiating the polymerization and apparatus therefor

A method of terminating a gas phase polymerization of an olefin to be conducted subsequent to producing a polyolefin by feeding a gaseous olefin into a fluidized bed reactor to polymerize the gaseous olefin while holding solid particles containing a catalyst in a fluid state,

• said method comprising introducing a deactivator in the fluidized bed reactor through at least two deactivator introduction ports of the fluidized bed reactor so as to terminate the gas phase polymerization,
• wherein the fluidized bed reactor has a fluidized bed having a height of at least 3 m, and
• wherein the deactivator is introduced in the fluidized bed reactor having a gas distributor plate provided therein through:
• 2-20 deactivator introduction ports spaced around said fluidized bed and disposed at height Ha (cm) as measured from the gas distributor plate, said height Ha satisfying the relationship:
• Ha=-0.3 D to 0.3 D
• wherein D represent the inside diameter (cm) of the fluidized bed reactor.

A method of terminating a gas phase polymerization of an olefin to be conducted subsequent to producing a polyolefin by feeding a gaseous olefin into a fluidized bed reactor to polymerize the gaseous olefin while holding solid particles containing a catalyst in a fluid state,

• said method comprising introducing a deactivator in the fluidized bed reactor through at least two deactivator introduction ports of the fluidized bed reactor so as to terminate the gas phase polymerization,
• wherein the fluidized bed reactor has a fluidized bed having a height of at least 3 m, and
• wherein the deactivator is introduced in the fluidized bed reactor having a gas distributor plate provided therein through:
• 2-20 deactivator introduction ports spaced around said fluidized bed and disposed at a height Hb (cm) as measured from the gas distribution plate, said height Hb satisfying the relationship:
• Hb=0.3 D to 2.0 D
• wherein D represents the inside diameter (cm) of the fluidized bed reactor.

A method of a gas phase polymerization of an olefin, consisting essentially of the steps of:

• (i) feeding a gaseous olefin into a fluidized bed reactor to polymerize the gaseous olefin while holding solid particles containing a catalyst in a fluid state, thereby producing a polyolefin;
• (ii) introducing a deactivator in the fluidized bed reactor through at least two deactivator introduction ports of the fluidized bed reactor so as to terminate the gas phase polymerization;
• and
• (iii) subsequently feeding a gaseous olefin into the fluidized bed reactor to initiate a gas phase polymerization of the olefin in the presence of the solid particles remaining in the fluidized bed reactor.