Fluid bed reactor

• US 4,518,750 A
• Filed: 03/09/1983
• Issued: 05/21/1985
• Est. Priority Date: 03/10/1982
• Status: Expired due to Term

• Current Assignee: Montedison S.p.A. (Government of France)
• Original Assignee: Montedison S.p.A. (Government of France)
• Inventors: Govoni, Gabriele, Loconsolo, Mauro, Corazzari, Canzio, Di Stefano, Giovanni
• Primary Examiner(s): Schofer, Joseph L.
• Assistant Examiner(s): Babajko, S.
• Application Number:
  US06/473,553
• Time in Patent Office: 804 Days
• Field of Search: 422/143, 422/131, 422/311, 526/68, 526/88, 526/352
• US Class Current: 526/68
• CPC Class Codes: B01J 2208/00274 involving reactant vapours
• CPC Class Codes: B01J 2219/1946 conical
• CPC Class Codes: B01J 8/1818 Feeding of the fluidising gas B01J8/44 takes precedence
• CPC Class Codes: B01J 8/1827 the fluidising gas being a reactant
• CPC Class Codes: C08F 10/00 Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• CPC Class Codes: C08F 2/34 Polymerisation in gaseous state

Abstract

A fluid bed reactor, suited for recycling a fluidizing gas containing, in suspension, particles of solid material; comprising a gas distributor consisting of a doubleconed body or of a series of concentrical cones provided on their lateral surfaces with ribs or fins forming gas inflow channels shaped in such a way and with such an inclination as to allow the passage of the solid particles entrained in the gas flow, and such as to hinder the outflow of the solid material that has been fluidized, when the flow of the gas is interrupted.

Claims

1. Process for the polymerization and copolymerization of alpha-olefins in a gaseous phase, on a fluid bed conssiting of polymerized material containing a catalyst, characterized in that said process is carried out in a fluid bed reactor comprising a distributor of fluidization gases which comprises a double cone body consisting of:

(a) a lower conical element, arranged with the vertex turned downwards, provided with more than two ribs on the lateral surface, said ribs having such a profile as to form, together with the wall of the containing shell, flow channels with a decreasing cross-section in an upward direction so that the velocity of the gas will increase gradually and correspondingly, the ribs being arranged diametrically opposite to each other with an axial symmetry and with an inclination with respect to the vertical such as to impart to the inflowing gas current a tangential component, the profile and inclination of the ribs being such as to allow the passage of the solid particles entrained by the inflowing gas, and so as to hinder the falling back of the particles of the fluidized bed whenever the feeding in of the gas is interrupted; and

of

(b) an upper conical element, wth its vertex turned upwards, superimposed onto the lower conical element and having the function of activating the circulation of the solid in the fluidized bed, eliminating the dead or stagnation zones, said process being further characterized in that the distributor in the fluid bed reactor in which it is carried out comprises devices for recycling of the gas, which distributor and the recycling devices allow the passage of the solid particles of the fluidized material entrained by the recylcing gas.

2. Process for the copolymerization of ethylene and propylene in a gaseous phase, on a fluid bed consisting of a polymerized material containing a catalyst, under such processing conditions as to obtain an amorphous copolymer, said process being characterized in that it is carried out in a fluid bed reactor comprising a distributor of fluidization gases which comprises a double cone body consisting of:

(a) a lower conical element, arranged with the vertex turned downwards, provided with more than two ribs on the lateral surface, said ribs having such a profile as to form, together with the wall of the containing shell, flow channels with a decreasing cross-section in an upward direction so that the velocity of the gas will increase gradually and correspondingly, the ribs being arranged diametrically opposite to each other with an axial symmetry and with an inclination with respect to the vertical such as to impart to the inflowing gas current a tangential component, the profile and inclination of the ribs being such as to allow the passage of the solid particles entrained by the inflowing gas, and so as to hinder the falling back of the particles of the fluidized bed whenever the feeding in of the gas is interrupted; and

of

(b) an upper conical element, with its vertex turned upwards, superimposed onto the lower conical element and having the function of activating the circulation of the solid in the fluidized bed, eliminating the dead or stagnation zones, said process being further characterized in that the distributor in the fluid bed reactor in which it is carried out comprises devices for recycling of the gas, which distributor and the recycling devices allow the passage of the solid particles of the fluidized material entrained by the recycling gas.