Abstract: Reactor systems suitable for the polymerization of an olefin monomer including first and second loop reactors effective for the polymerization of an olefin monomer and polymers formed therefrom are described herein.

Abstract: Polyesters such as polyethylene, polypropylene and polybutylene terephthalate are made from melts of precondensates of polyesters by first conducting vapors comprising precondensate components distributed in the form of an aerosol through a polycondensation reactor in which precondensate components are deposited on the reactor wall and in an outlet chamber of the reactor on a separator. Then the deposits are conducted to the unstirred discharge sump. Upper layers of the discharge sump are continuously recirculated in the stirred reactor area and thus subjected to reconversion and further polycondensation.

Abstract: A method for hydrolyzing/condensing, by acid catalysis, silanes bearing hydrolyzable groups, preferably halogenosilanes and more preferably still chlorosilanes, in a polyphase reaction medium (preferably biphasic), includes contacting the silanes bearing the hydrolyzable groups with water, buffer solution and neutralizing agent, while stirring, then in separating the aqueous phase from the organic phase, which contains the hydrolysis/condensation products, namely hydroxylated polyorganosiloxanes; such method is characterized by (a) employing intensively stirring means producing, in the reaction medium, an agitation at least equivalent to that induced by a shearing corresponding to that provided by a rotor whereof the peripheral speed is not less than 8 m.s?1, preferably not less than 10 m.s?1, and more preferably still ranging between 15 and 20 m.s?1, enabling thus organic phase droplets to be formed, of d32 less than 500 ?m; and (b) ensuring that the silanes/aqueous phase mass fraction is not less than 0.

Abstract: The present invention discloses multiple loop reactor wherein one of the settling legs transferring polymer product from one loop to a further loop can be taken out of service or re-opened without interfering with the operation of said multiple loop reactor.

Abstract: A polymerization reactor comprising a circulation loop, an inlet for raw material, an outlet, driving means for circulating a reactor charge within the circulation loop, and a pig station for storing, launching, and receiving cleaning pigs. The pig station comprises a lid to cover an opening enabling removal of the cleaning pig. The pig station is constructed as a box with a cylindrical bore connected at both ends to the circulation loop, the bore having a central part with a diameter which is larger than the inner diameter of the circulation loop. At a transitional part at the outer ends of the bore the bore diameter narrows down to be substantially equal to the inner tube diameter of the circulation loop. Over at least a part of the inner bore substantially half of the circular cross-section is formed in the removable lid.

Abstract: A polymerisation reactor comprising one or more circulation loops with one or more inlets for raw material, one or more outlets, and a circulation pump for circulating a reactor charge within the circulation loop. A by-pass line for by-passing the circulation pump connects a point of the loop upstream of the pump with a point downstream of the pump, both points being provided with a three way valve.

Abstract: The present invention relates to a loop reactor suitable for olefin polymerization process comprising: a plurality of interconnected pipes defining a flow path for a polymer slurry, said slurry consisting essentially of an olefin reactant, a polymerization catalyst, liquid diluent and solid olefin polymer particles, means for introducing olefin reactant, polymerization catalyst and diluent into said reactor, a pump suitable for maintaining the polymer slurry in circulation in said reactor, and single settling leg connected to said loop reactor through (a) a take off line extending from said reactor to said settling leg and configured to remove said polymer slurry from said reactor, and (b) a return line extending from said settling leg to said reactor, characterized in that said take off line is radially connected to said single settling leg.

Abstract: The present disclosure relates, according to some embodiments, to compositions, apparatus, methods, and systems that may be used to produce polyols, for example, polyether polyols with a narrow range of molecular weights, with little if any unsaturated byproducts, in a sustained and/or continuous reaction, with efficient heat transfer, and/or at high production rates. For example, in some embodiments, teachings of the disclosure may be used to produce polyether polyols in a continuous loop flow process. A continuous loop flow process may be practiced such that heat is effectively transferred and/or product properties (e.g., range of molecular weights) are controllable. For example, a continuous loop flow process may use one or more continuous flow loops comprising a heat exchanger, a means to move material around each loop, inlets for catalyst, monomer, initiator or starter, and an outlet for polyol product.

Abstract: A process for producing polymer and more particularly adhesive using a recirculating loop reactor. In one embodiment the reactor includes one or more mixers to mix feed stock with the polymerized material recirculating in the reactor. In another embodiment a planetary roller extruder (PRE) may be used for this purpose. In still another embodiment, a combination of one or more static mixers and one or more PREs may be used.

Abstract: The present invention relates to an apparatus for preparing and supplying catalyst to an ethylene slurry loop polymerisation reactor and to an apparatus for controlling the injection of catalyst slurry in a polymerization reactor wherein polyethylene is prepared. The present invention a Iso relates to a method for optimising catalyst supply to a polymerisation reactor. The diluted catalyst is transferred to the reactor (1) using a membrane pump (5) controllable in function of the concentration of a reactant in said reactor (1).

Abstract: A polymerisation reactor (1) comprising a circulation loop (2), an inlet for raw material (3), an outlet (5), driving means for (6) circulating a reactor charge within the circulation loop (2), and a pig station (7) for storing, launching, and receiving cleaning pigs. The pig station (7) comprises a lid to cover an opening enabling removal of the cleaning pig. The pig station (7) is constructed as a box with a cylindrical bore connected at both ends to the circulation loop, the bore having a central part with a diameter which is larger than the inner diameter of the circulation loop. At a transitional part at the outer ends of the bore the bore diameter narrows down to be substantially equal to the inner tube diameter of the circulation vloop. Over at least a part of the inner bore substantially half of the circular cross-section is formed in the removable lid.

Abstract: The pump assembly includes an impeller rotatably mounted in a pipe of the reactor having blades that generate a flow of fluid slurry through the pipe, a nosecone protruding in an upstream direction in front of the impeller blades that rotates along with the blades, and a plurality of stationary guide vanes connected to the housing upstream of the impeller blades and having free ends that are radially spaced apart from the nosecone. The leading edges of the stationary vanes are shaped to direct any stringy material into the radial gaps between the free ends of the stationary vanes and the rotating nose cone to be shredded and thus prevent fouling and clogging of the pump assembly when such stringy material is generated during the polymerization process.

Abstract: A process for the polymerization of olefin's, including: introducing an olefin and a polymerization catalyst into a polymerization reactor to form a polyolefin, the polymerization reactor including: a fluidized bed region having a top and a bottom; and a motive bed region; wherein a first end of the motive bed region is fluidly connected to the top of the fluidized bed region; and wherein a second end of the motive bed region is fluidly connected to the bottom of the fluidized bed region; and wherein a diameter of the fluidized bed region is greater than a diameter of the motive bed region; circulating at least a portion of the olefin, the catalyst, and the polyolefin through the fluidized bed region and the motive bed region; maintaining a dense-phase fluidized bed within the fluidized bed region; recovering polyolefin from the fluidized bed region, is provided. A reactor system directed to the process is also provided.

Abstract: The present invention provides a sugar chain synthesizer capable of continuously reacting sugar chains when a plurality of sugar chains are successively reacted. The sugar chain synthesizer of the present invention includes a plurality of vessels containing respective sugar nucleotide solutions, a plurality of vessels containing respective glycosyltransferases, and a reactor containing a primer that is a water-soluble polymer, into which the above described sugar nucleotide solution and glycosyltransferase are introduced. In the present invention, components in a reaction solution obtained in the reactor are separated through an ultrafiltration column, and a reaction product is then returned to the above described reactor, so as to continuously synthesize sugar chains. Although it is a complicated synthesis of sugar chains, it becomes possible to carry out such synthesis continuously and automatically.

Abstract: An apparatus (2) includes a neutralization tank (3), a pump (4), a heat exchanger (6), a line mixer (8), a polymerizer (10), a first pipe (12), a second pipe (14), a third pipe (16), a fourth pipe (18), and a fifth pipe (20). Continuously supplied into the neutralization tank (3) are a monomer aqueous solution and a basic aqueous solution, so as to prepare a mixture solution. The mixture solution is circulated through the first pipe (12), the pump (4), the second pipe (14), the heat exchanger (6), and the third pipe (16). The mixture solution is supplied to the polymerizer through the fourth pipe (18).

Abstract: A tubular reactor for use in polymerisation reactions is described, having a design pressure PR of 40-65 barg, at least a portion of which is oriented vertically and at least part of which vertical portion is surrounded by a concentric jacket for the passage of cooling fluid, wherein the design pressure in barg of the jacket PJ is less than 0.0018.PR2.25. Another aspect of the invention concerns a tubular reactor for use in polymerisation reactions having a design pressure PR of 40-65 barg, at least a portion of which is oriented vertically and at least part of which vertical portion is surrounded by a concentric jacket for the passage of cooling fluid, wherein the actual thickness of the reactor wall is either no more than 2 mm greater and/or no more than 10% greater than the minimum wall thickness required to withstand the design pressure PR as calculated according to the ASME Boiler and Pressure Vessel code.

Abstract: Method of emulsion polymerization wherein a reactor comprising a closed reactor loop is continuously charged with fresh monomers and water phase at substantially the same rate as the rate of an overflow of reactor charge discharged into a secondary line section. The reactor charge is continuously recirculated within the reactor loop. The discharge rate and the circulation rate in the loop are balanced such as to result in a monomer content in the loop of less than 12 wt. %. The secondary line section has a volume of less than twice the volume of the reactor loop.

Abstract: The present invention describes a reactor comprising two interconnected loops wherein the growing polymer flows continuously in circuit from the first loop to the second loop through a First pipe and back to the first loop through a second pipe. It also discloses process for polymerising olefins in two interconnected loop reactors.

Abstract: A process for the discontinuous production of granules from polycondensation polymers by precondensation of an oligomer at 5 to 400 mbar and subsequent polycondensation in a stirring reactor and subsequent granulation. In the vicinity of the outlet port, the density of the entraining surfaces lies between 1 and 8 m2 per m3 reactor space and constantly increases with increasing distance from the discharge region. Inside the reactor, there is a viscosity gradient between the region most remote from the discharge port and the zone of the discharge port. The thermal decomposition of the polymer melt flowing out of the reactor is compensated during granulation. The stirring reactor with horizontal longitudinal axis approximately has the shape of a single or double truncated cone. The reactor has rotatable, vertical product entraining surfaces and stationary scrapers between the same.

Abstract: An olefin polymerization reactor according to the present invention comprises: a vertically extending cylinder; a decreasing diameter portion on the cylinder, having an inside diameter that decreases progressively downward, and having a gas inlet orifice at a bottom end thereof; and a plurality of through holes passing through from an outside surface towards an inside surface of the decreasing diameter portion. Inside a reaction zone enclosed by an inside surface of the decreasing diameter portion and an inside surface above the decreasing diameter portion of the cylinder, a spouted-fluidized bed or a spouted bed is formed.

Abstract: A process for the multistage polymerization of olefins in a sequence of an upstream slurry reactor and a downstream gas-phase reactor, the transfer of polymer from the upstream reactor to the downstream reactor comprising the following steps: a) heating the slurry of polyolefin particles to evaporate the liquid polymerization medium; b) separating the polyolefin particles from the obtained gaseous phase in at least a separation chamber; c) transferring the polyolefin particles to said downstream reactor by means of a couple of lock hoppers working intermittently in parallel, where one of said lock hoppers is continuously filled with the polymer coming from said separation chamber, while simultaneously the other one is continuously pressurized by means of a gas comprising the reaction mixture coming from said downstream reactor.

Abstract: A polyester production facility capable of producing an esterified product stream having a low impurity concentration relative to product streams produced in conventional polyester production facilities.

Abstract: A process for producing polymer and more particularly adhesive using a recirculating loop reactor. In one embodiment the reactor includes one or more mixers to mix feed stock with the polymerized material recirculating in the reactor. In another embodiment a planetary roller extruder (PRE) may be used for this purpose. In still another embodiment, a combination of one or more static mixers and one or more PREs may be used.

Abstract: Reactor systems suitable for the polymerization of an olefin monomer including first and second loop reactors effective for the polymerization of an olefin monomer and polymers formed therefrom are described herein.

Abstract: A process comprising polymerizing an olefin monomer optionally together with an olefin comonomer in the presence of a polymerization catalyst in a diluent in a loop reactor which comprises at least 2 horizontal sections and at least 2 vertical sections to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the Froude number in at least 20% of the length of the vertical sections of the reactor loop is less than 85% of the Froude number in at least 20% of the length of the horizontal sections of the loop is disclosed.

Abstract: Methods for supplying a catalyst to an ethylene slurry loop polymerization reactor and polymers formed therefrom are described herein. The method generally includes preparing a catalyst slurry in a preparation vessel wherein the slurry includes a hydrocarbon diluent liquid which contains a Ziegler-Natta catalyst; supplying the catalyst slurry from the preparation vessel to a buffer vessel; withdrawing the catalyst slurry from the buffer vessel and supplying the catalyst slurry to a slurry loop polymerization reactor in which ethylene is polymerized; mixing a co-catalyst with the Ziegler Natta catalyst in the slurry prior to the supplying of the catalyst slurry to the slurry loop polymerization reactor; and controlling the transfer of catalyst slurry from the preparation vessel to the buffer vessel and the withdrawal of catalyst slurry from the buffer vessel to maintain the level of catalyst slurry in the buffer vessel substantially constant relative to the level of catalyst slurry in the preparation vessel.

Abstract: Process and apparatus for continuously producing olefin polymers in a slurry phase reactor in a hydrocarbon diluent or liquid monomer. The process comprises continuously withdrawing from the slurry phase reactor a polymer slurry containing polymer and a fluid phase, which contains hydrocarbons and optionally hydrogen, and concentrating the slurry with a self-cleaning screen by removing a part of the fluid phase to provide a concentrated slurry. The openings of the screen, which can have a planar or cylindrical configuration, are smallest at the inflow surface of the screen and increases towards the outflow surface. By the present invention, the need for service and maintenance is significantly reduced.

Abstract: A polymerisation reactor comprising one or more circulation loops with one or more inlets for raw material, one or more outlets, and a circulation pump for circulating a reactor charge within the circulation loop. A by-pass line for by-passing the circulation pump connects a point of the loop upstream of the pump with a point downstream of the pump, both points being provided with a three way valve.

Abstract: A process for the separation of volatile material from particulate polymer discharged from a polymerisation reactor in the form of a polymer slurry and which has been substantially freed from unreacted monomer in an earlier separation step, comprising (a) feeding the particulate polymer to a purge vessel and causing it to move through the vessel in substantially plug-flow mode, (b) heating the particulate polymer in the purge vessel to a temperature greater than 30° C.

Abstract: A process comprising polymerising in a loop reactor an olefin monomer optionally together with an olefin commoner in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the Froude number is maintained at or below 20 is disclosed.

Abstract: An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.

Abstract: A process comprising polymerising in a loop reactor of continuous tubular construction an olefin monomer optionally together with an olefin comonomer in the presence of a polymerisation catalyst in a diluent to produce a slurry comprising solid particulate olefin polymer and the diluent wherein the internal diameter of at least 50% of the total length of the reactor is at least 700 millimeters and the solids concentration in the reactor is at least 20 volume % is disclosed.

Abstract: The present invention relates to a process for the catalytic polymerization of olefins comprising the steps of; i) a first polymerization in a first reactor, wherein olefins are polymerized with a particulate catalyst, hydrogen and optional a comonomer in a fluidum of an inert low boiling hydrocarbon medium into an reaction mixture comprising polymerized olefins; and ii) a second polymerization in a second reactor, wherein the polymerized olefins are further polymerized in a fluidized bed and in a moving bed under such conditions that the residence time in the fluidized bed and the residence time in the moving bed are independently controlled to a reactor system for carrying out said process, to the use of the reactor system, the polyolefins obtainable with said method and to the use of these polyolefins.

Abstract: The invention relates to a process for the catalytic polymerization of olefins, wherein olefins are contacted with a particulate catalyst in a fluidized bed and in a moving bed such that the residence time in the fluidized bed and the residence time in the moving bed are independently controlled, to a reactor system comprising a fluidized bed reactor provided with a reactant inlet, a product outlet and means for maintaining a fluidized bed in the fluidized bed reactor and with a moving bed reactor provided with an inlet directly connected to the fluidized bed reactor and an outlet connected to the fluidized bed reactor such that the residence time in the fluidized bed reactor and the residence in the moving bed reactor are independently controlled, and to its use for the catalytic polymerization of olefins.

Abstract: An apparatus for continuously producing polyisocyanate is provided for quickly contacting polyamine and carbonyl chloride in order to suppress an undesirable reaction between polyamine and polyisocyanate so that a by-product can be reduced and the yield of polyisocyanate can be improved. In a circulatory line 7, a material-mixing portion 8, a high-shear pump 3, a reactor 4, a liquid-feeding pump 5 and a cooler 6 are interposed in series along the direction of the flow of a reaction solution, thereby forming a closed line. In this apparatus 1, after polyamine and carbonyl chloride are supplied in the material-mixing portion 8, the reaction solution is sheared by the high-shear pump 3 in a state where the contact of the polyamine with the reaction solution is minimized. Thus, the formation of a urea compound as a by-product can be suppressed and the yield of polyisocyanate can be improved.

Abstract: The object of the present invention is to provide a production method of a high molecular weight aromatic polycarbonate containing a reduced amount of a high melting point product, and having less thermal history received and excellent hue by a melt process. The present invention relates to a production method of an aromatic polycarbonate, characterized in that in producing an aromatic polycarbonate using an aromatic dihydroxy compound and a carbonic diester as raw materials and using plural reactors, a molten reactant temperature T1 (° C.) in at least one reactor A and a molten reactant temperature T2 (° C.) in a reactor B subsequent to the reactor A are satisfied with the relationship of T2<T1, and an evaporation surface area per unit treatment amount of a molten reactant in the reactor to which a molten reactant having a limiting viscosity of 0.1 dl/g or more is supplied is 1.0 m2·hr/m3 or more.

Abstract: Methods of dehydrogenating hydrocarbons to yield unsaturated compounds are described. Reactor configurations useful for dehydrogenation are also described. Hydrocarbons can be dehydrogenated, for relatively long periods of time-on-stream, in a reaction chamber having a dimension of 2 mm or less to produce H2 and an olefin. Techniques have been developed that reduce coke and allow stable, relatively long-term operation in small reactors.

Abstract: Tubular reactor apparatus and processes are provided for improved polymerization including using chain transfer agents and multiple monomer feeds spaced lengthwise along the tubular reactor providing high conversions of monomer into polymer. The invention also relates to polymers made from such a tubular reactor apparatus and processes including those polymers having a low haze value, a density over 0.92 g/cm3 and/or having terminal carbonyl groups. The apparatus and methods uncouple or reduce the dependency between the monomer concentration and transfer agent concentration. The uncoupling in other embodiments may also be varied leading to multiple desirable effects.

Abstract: A process is provided for recovering polymer solids from a polymerisation reactor effluent. The process comprises extracting the polymerisation effluent from a polymerisation reactor; passing the effluent, or a part thereof, to a flash vessel for flashing liquid in the effluent to vapour, and removing said vapour from said flash vessel; passing the polymer solids from the flash vessel to a transfer apparatus which comprises a transfer vessel; passing the polymer solids from the transfer vessel to a purging means for removing residual liquid from the polymer solids; wherein the polymer solids are passed from the flash vessel to the purging means in a continuous flow such that a quantity of polymer solids is maintained in the transfer vessel. An apparatus for performing the process is also provided.

Abstract: The present invention discloses a slurry loop reactor having at least two loops (1, 2) and comprising a by-pass line (11) connecting two points (12, 13) of the same loop reactor by an alternate route having a different transit time than that of the main route, said by-pass line also collecting the growing polymer of a first loop reactor (1) and sending said growing polymer to an entry point (13) in a second reactor (2).

Abstract: The present invention concerns a process and an apparatus for continuous polymerisation of olefin monomers. In particular, the present invention concerns a process and an apparatus for continuous polymerisation olefin monomers like ethylene and other monomers, wherein an olefin monomer is polymerised in slurry phase in an inert hydrocarbon diluent in at least one loop reactor. According to the invention, a polymer slurry is continuously withdrawn from the loop reactor and concentrated. The concentrated slurry is conducted to a flash unit in order to remove the remaining fluid phase, and gas obtained is compressed in a flash gas compressor before it is being fed to a distillation section. By means of the present invention it is possible reduce the size of the flash gas compressor and the capacity of the distillation sections. This significantly reduces investment cost for a continuously operated polymerization apparatus.

Abstract: An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.

Abstract: Techniques are provided for producing polymer particles of a size just slightly larger than the size of polymer fines. The technique may prevent or limit the occurrence of reactor fouls associated with large polymer particles. The technique also may provide a greater weight percentage of solids in the reactor. The desired polymer particle size may be achieved by employing a catalyst having particles of a size determined based on the expected catalyst productivity. In certain embodiments, the catalyst particle size may be determined based on the expected catalyst productivity, the polymer particle density, the catalyst particle density, and/or the polymer particle size.

Abstract: Aspects of the invention are directed to a process for producing polypropylene comprising: providing series reactors comprising a first and a second loop allowing flow of polypropylene, catalyst, hydrogen and propylene there between, wherein each loop comprises from six to eight legs, each leg having fluid connections there between; injecting into the first loop an amount of a catalyst, propylene and optionally hydrogen; withdrawing polypropylene, and unreacted propylene and optionally unreacted hydrogen from the first loop and injecting the polypropylene, and unreacted propylene and optionally unreacted hydrogen into the second loop; and providing a propylene/polypropylene separator fluidly connected to the second loop and isolating polypropylene therefrom. In one embodiment a recycle conduit is provided between the propylene/polypropylene separator and the second loop allowing the recycling of unreacted propylene and optionally hydrogen into the second loop.

Abstract: A polyisocyanate production system is provided that can stably produce chlorine from hydrogen chloride produced secondarily while reacting stably between carbonyl chloride and polyamine and can perform an effective treatment of the hydrochloric gas produced secondarily. A hydrochloric gas control unit 32 controls a flow-rate control valve 23 to keep constant an amount of hydrogen chloride supplied from a hydrogen chloride purifying tank 4 to a hydrogen chloride oxidation reactor 6 via a second hydrochloric-gas connection line 11 to be constant, and also controls a pressure control valve 22 based on an inner pressure of the hydrogen chloride purifying tank 4 input from a pressure sensor 25 to discharge the hydrochloric gas from the hydrogen chloride purifying tank 4 to the hydrogen chloride absorbing column 5 via a first hydrochloric-gas connection line 10, so as to keep an inner pressure of the hydrogen chloride purifying tank 4 to be constant.

Abstract: A process is disclosed for providing a flow of particulate matter such as a catalyst to a reactor, comprising intermittently adding said particulate matter and a diluent to a mixing tank, and continuously withdrawing a slurry of particulate matter in diluent from the mixing tank for introduction into the reactor, wherein prior to each addition of particulate matter and diluent to the mixing tank, the concentration of particulate matter in the diluent already in the mixing tank is measured or calculated, and the amount of particulate matter and diluent subsequently added is measured so as to achieve the same concentration at the end of the addition as that measured or calculated prior to the addition. Preferably measurement of the amount of particulate mailer and diluent added to the mixing tank is carried out before any diluent is added to the particulate matter.

Abstract: The present invention relates to a polymerization process for producing olefin polymers in a loop reactor comprising two or more settling legs, comprising the steps of: —introducing into the loop reactor one or more olefin reactants, polymerization catalysts and diluents, and while circulating said reactants, catalysts and diluents; —polymerizing said one or more olefin reactants to produce a polymer slurry comprising essentially liquid diluent and solid olefin polymer particles; said process further comprising one or more cycles of: (a) allowing said polymer slurry to settle into said setting legs, and (b) sequentially discharging said settled polymer slurry from said two or more settling legs out of the reactor, whereby the aggregate time of discharge of all the legs is more than 50%, preferentially more than 80% and most preferably more than 95% of the time interval between two triggerings of the same settling leg.

Abstract: The present invention provides a process for cooling a polymerization reactor having at least four leg jackets. In the four leg jacket embodiment, the process comprises pumping a first coolant through a first pair of leg jackets, and pumping a second coolant through a different pair of leg jackets. In this process, the first coolant does not contact the second coolant while inside the leg jackets.

Abstract: A system and method for measuring pressure and flow rate of polymer slurry circulating in a loop reactor. For flow rate measurement, the loop reactor has a pressure tap on an outside radius of an elbow of the loop and a pressure tap on an inside radius of the elbow. The pressure taps incorporate diaphragms. Sensing legs couple the pressure taps with a differential pressure meter configured to provide a signal indicative of the flow rate of the polymer slurry. For pressure measurement, pressure taps without diaphragms at the loop reactor wall may be disposed at various points along the loop reactor, the pressure taps coupled to pressure sensing lines. A diluent flush line having a screen disposed therein may provide diluent to the pressure taps. The screen may reduce fouling of the pressure tap and sensing line with solids from the reactor.

Abstract: A process for the polymerisation of ethylene and optionally at least one C3-20 alpha olefin comonomer in the slurry or solution phase in a reactor having a polymer outlet stream, a procatalyst or catalyst feed stream and a hydrogen feed stream, said polymerisation being effected in the presence of a metallocene catalyst, a diluent and hydrogen, wherein said diluent is recycled from said outlet stream to said hydrogen feed stream, said procatalyst or catalyst feed stream is free of hydrogen, said hydrogen feed stream is free of procatalyst or catalyst and said procatalyst or catalyst feed stream does not comprise recycled diluent.