Abstract: Systems and methods useful in determining the superficial gas velocity in fluidized bed reactors may utilize a pressure drop across a portion of the system but not associated with a flowmeter. For example, method may comprise: obtaining a pressure for each of two different locations within a fluidized bed reactor system that comprises a reactor capable of containing a fluidized bed and a cycle gas loop, wherein one or both of the two different locations is not at a flowmeter; calculating a pressure drop based on the two pressures; calculating a first superficial gas velocity (SGValt) for the fluidized bed based on the pressure drop; and operating the fluidized bed reactor system based at least in part on the SGValt.

Abstract: In a gas phase fluidized bed polymerization process for the production of polyolefin polymers, such as polyethylene polymers or polypropylene polymers, loss of ethylene or propylene accompanying inert gas purging is reduced by passing an ethylene- or propylene-containing purge stream through a vent column to contact a hydrocarbon liquid flowing through the vent column contercurrent to the purge stream whereby unreacted ethylene or propylene in the purge stream portion is dissolved in the hydrocarbon liquid to produce an ethylene- or propylene-enriched liquid stream and an ethylene- or propylene-depleted gaseous stream. The ethylene- or propylene-enriched liquid stream is then recycled to the fluidized bed reactor, while at least part of the ethylene- or propylene-depleted gaseous stream is purged.

Abstract: In a gas phase fluidized bed polymerization process for the production of polyolefin polymers, such as polyethylene polymers or polypropylene polymers, loss of ethylene or propylene accompanying inert gas purging is reduced by passing an ethylene- or propylene-containing purge stream through a vent column to contact a hydrocarbon liquid flowing through the vent column contercurrent to the purge stream whereby unreacted ethylene or propylene in the purge stream portion is dissolved in the hydrocarbon liquid to produce an ethylene- or propylene-enriched liquid stream and an ethylene- or propylene-depleted gaseous stream. The ethylene- or propylene-enriched liquid stream is then recycled to the fluidized bed reactor, while at least part of the ethylene- or propylene-depleted gaseous stream is purged.

Abstract: A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The system includes a fluidized bed pressure vessel, settling vessels, discharge lines, primary discharge valves, vent lines, primary vent valves, crosstie lines, crosstie valves, and primary exit valves wherein the system is absent a transfer tank, and absent a filter element. The method provides for transferring a solid/gas mixture via a discharge line from the pressure vessel to a settling vessel, wherein gas is separated from the mixture, and the gas is transferred to at least one other settling vessel via a crosstie line. After the solids are transferred out of the settling vessel, the empty vessel then receives gas from other settling vessels in the system.

Abstract: Catalyst feed systems and processes utilizing such systems are described herein. Some embodiments disclosed herein relate to a process for improving the flowability of catalyst in a catalyst feed system, including providing a catalyst feed vessel with at least one heat exchange system for maintaining the catalyst system temperature below a critical flow temperature. Also disclosed is a catalyst feed system for the polymerization of olefins including a catalyst feed vessel; and a heat exchange system for maintaining a temperature of a catalyst within the catalyst feed vessel. Additionally disclosed is a process for polymerization of olefins including maintaining a supported catalyst in a catalyst feed vessel below a critical flow temperature of the catalyst; feeding the catalyst to a polymerization reactor; and contacting the catalyst with an olefin to form a polyolefin.

Abstract: Catalyst feed systems and processes utilizing such systems are described herein. Some embodiments disclosed herein relate to a process for improving the flowability of catalyst in a catalyst feed system, including providing a catalyst feed vessel with at least one heat exchange system for maintaining the catalyst system temperature below a critical flow temperature. Also disclosed is a catalyst feed system for the polymerization of olefins including a catalyst feed vessel; and a heat exchange system for maintaining a temperature of a catalyst within the catalyst feed vessel. Additionally disclosed is a process for polymerization of olefins including maintaining a supported catalyst in a catalyst feed vessel below a critical flow temperature of the catalyst; feeding the catalyst to a polymerization reactor; and contacting the catalyst with an olefin to form a polyolefin.

Abstract: Catalyst feed systems and processes utilizing such systems are described herein. Some embodiments disclosed herein relate to a process for improving the flowability of catalyst in a catalyst feed system, including providing a catalyst feed vessel with at least one heat exchange system for maintaining the catalyst system temperature below a critical flow temperature. Also disclosed is a catalyst feed system for the polymerization of olefins including a catalyst feed vessel; and a heat exchange system for maintaining a temperature of a catalyst within the catalyst feed vessel. Additionally disclosed is a process for polymerization of olefins including maintaining a supported catalyst in a catalyst feed vessel below a critical flow temperature of the catalyst; feeding the catalyst to a polymerization reactor; and contacting the catalyst with an olefin to form a polyolefin.

Abstract: A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The discharge system includes a fluidized bed pressure vessel, a settling vessel, a transfer vessel, discharge line, primary discharge valve, and primary exit valve. Also in included is a method to operate the discharge system. The method includes transferring a solid/gas mixture from a fluidized bed pressure vessel to a settling vessel, transferring the solids to a transfer vessel, and then emptying the transfer vessel.

Abstract: Catalyst feed systems and processes utilizing such systems are described herein. Some embodiments disclosed herein relate to a process for improving the flowability of catalyst in a catalyst feed system, including providing a catalyst feed vessel with at least one heat exchange system for maintaining the catalyst system temperature below a critical flow temperature. Also disclosed is a catalyst feed system for the polymerization of olefins including a catalyst feed vessel; and a heat exchange system for maintaining a temperature of a catalyst within the catalyst feed vessel. Additionally disclosed is a process for polymerization of olefins including maintaining a supported catalyst in a catalyst feed vessel below a critical flow temperature of the catalyst; feeding the catalyst to a polymerization reactor; and contacting the catalyst with an olefin to form a polyolefin.

Abstract: A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The system includes a fluidized bed pressure vessel, settling vessels, discharge lines, primary discharge valves, vent lines, primary vent valves, crosstie lines, crosstie valves, and primary exit valves wherein the system is absent a transfer tank, and absent a filter element. The method provides for transferring a solid/gas mixture via a discharge line from the pressure vessel to a settling vessel, wherein gas is separated from the mixture, and the gas is transferred to at least one other settling vessel via a crosstie line. After the solids are transferred out of the settling vessel, the empty vessel then receives gas from other settling vessels in the system.

Abstract: A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The discharge system includes a fluidized bed pressure vessel, a settling vessel, a transfer vessel, discharge line, primary discharge valve, and primary exit valve. Also in included is a method to operate the discharge system. The method includes transferring a solid/gas mixture from a fluidized bed pressure vessel to a settling vessel, transferring the solids to a transfer vessel, and then emptying the transfer vessel.