Abstract: The present invention relates to a method for performing a polymerization process in a stirred reactor, wherein a critical time window is determined by means of a monitor of at least one polymerization process parameter and an associated process window, and when a critical time window is present, an adaptation of process conditions is made in order to configure the polymerization process to conform to the process window.

Abstract: A method according to one embodiment includes operating a reactor or providing a reactor after operation, wherein the reactor includes a bottom section, a bed section above the bottom section, a distributor plate between the bottom section and the bed section, an expanded section above the bed section, and an upper section above the bed section, wherein the bed section has a height H measured from the distributor plate to the expanded section; measuring a concentration of particulates in the upper section of the reactor to obtain a first determined level of particulates in the upper section; and discharging at least some of the particulates from the reactor at an upper discharge point located above 0.55H as measured vertically from the distributor plate based on the first determined level. Additional systems and methods are also provided.

Abstract: A method according to one embodiment includes operating a reactor or providing a reactor after operation, wherein the reactor includes a bottom section, a bed section above the bottom section, a distributor plate between the bottom section and the bed section, an expanded section above the bed section, and an upper section above the bed section, wherein the bed section has a height H measured from the distributor plate to the expanded section; measuring a concentration of particulates in the upper section of the reactor to obtain a first determined level of particulates in the upper section; and discharging at least some of the particulates from the reactor at an upper discharge point located above 0.55H as measured vertically from the distributor plate based on the first determined level. Additional systems and methods are also provided.

Abstract: Disclosed herein are various methods and systems for gas and liquid phase polymer production. In certain embodiments, the methods comprise manipulating properties of polymers produced by adjusting the hydrogen feed rate.

Abstract: Embodiments of the invention provide a method of controlling a gas-phase polymerization process. The method includes determining a difference between a control variable of the polymerization process, such as the production rate, and the desired value of the control variable; adjusting or maintaining a first manipulated variable to at least partially compensate for the difference between the control variable and the desired value; and adjusting or maintaining a second manipulated variable to at least partially compensate for the effect of adjusting or maintaining the first manipulated variable.

Abstract: The invention is directed to a polymerization system and method of controlling resin properties during the production of bimodal and multimodal polymer compositions using at least one manipulated variable to minimize dynamic deviations from polymer characteristics. In particular embodiments, the method of control includes determining a property of the resin based on a current and/or previous values or estimates or process variables or polymer characteristics. In this manner the control actions serve to reduce process upsets or facilitate in transitioning to a new product or grade to reduce the amount of off-grade resin material produced during transition or during steady state manufacture.

Abstract: The present invention relates to a method for degassing polymer powder comprising flushing the polymer powder in a first chamber with a first flow of flushing gas, transferring the polymer powder into a second chamber and flushing the polymer powder with a second flow of flushing gas in said second chamber. The present invention also relates to a system suitable for carrying out this method.

Abstract: The present invention relates generally to polyolefin production and to reducing volatile organic content (VOC) associated with the polyolefin. Techniques include the construction and implementation of a purge column model to calculate or estimate the VOC content in the polyolefin exiting the purge column. The techniques facilitate the design and operation of the polyolefin manufacturing process.

Abstract: A system and method for olefin polymerization is provided. The method includes polymerizing one or more olefins within a reactor having one or more injection tubes in fluid communication therewith, at least one of the one or more injection tubes having two or more concentric flow paths; flowing a catalyst through a first flow concentric path of the injection tube into the reactor; flowing one or more monomers through a second concentric flow path of the injection tube into the reactor; measuring rate of heat removal within the reactor; and adjusting the one or more monomers flow through the injection tube in response to the rate of heat removal in the reactor.

Abstract: A method for controlling a solution process for the polymerisation of olefins is disclosed. The method is based on an algorithm that calculates predicted operating parameters of the process, including calculation of the extent of reaction (?), as a function of the solution density (?), and then calculation of the whole composition of the solution. The algorithm resolves a system of equations comprising the equation of state in the PC-SAFT form, the Lewis-Mayo equation for monomer incorporation into a copolymer, and the stoichiometry equation. Predicted parameters are compared to target parameters to detect possible deviations and implement corresponding compensation in the feed.

Abstract: The invention relates to an improved process for manufacturing an olefin polymer composition, in particular polyethylene, that incorporates two or more reaction zones in an optimized configuration that ease product transitions and allows for improved reactor quality control.

Abstract: A method according to one embodiment includes operating a reactor or providing a reactor after operation, wherein the reactor includes a bottom section, a bed section above the bottom section, a distributor plate between the bottom section and the bed section, an expanded section above the bed section, and an upper section above the bed section, wherein the bed section has a height H measured from the distributor plate to the expanded section; measuring a concentration of particulates in the upper section of the reactor to obtain a first determined level of particulates in the upper section; and discharging at least some of the particulates from the reactor at an upper discharge point located above 0.55H as measured vertically from the distributor plate based on the first determined level. Additional systems and methods are also provided.

Abstract: Provided is a method for monitoring a polymerization reaction in a fluid bed reactor to determine in on-line fashion a current value, and preferably also a limiting value, of a stickiness control temperature, and optionally controlling the reaction in response thereto in an effort to prevent occurrence of a discontinuity event. The stickiness control temperature is a temperature indicative of a characteristic of melting behavior of polymer resin in the reactor, and may be indicative of occurrence of resin sheeting or another discontinuity event. Optionally , a predetermined relation between values of acoustic energy in the reactor and values of a stickiness control temperature in used to provide error checking for determination of the stickiness control temperature, or a current value of the stickiness control temperature is determined from acoustic data and a predetermined relation between values of an acoustic condition in the reactor and values of the stickiness control temperature.

Abstract: A system and method for olefin polymerization is provided. The method includes polymerizing one or more olefins within a reactor having one or more injection tubes in fluid communication therewith, at least one of the one or more injection tubes having two or more concentric flow paths; flowing a catalyst through a first flow concentric path of the injection tube into the reactor; flowing one or more monomers through a second concentric flow path of the injection tube into the reactor; measuring rate of heat removal within the reactor; and adjusting the one or more monomers flow through the injection tube in response to the rate of heat removal in the reactor.

Abstract: A method and apparatus are disclosed for controlling product discharge from a fluidized bed reactor and for minimizing the loss of the unreacted monomer in the fluidizing gas upon removing the solid polymer product from the reactor. The method and apparatus utilize at least one detector in the product tank or its vent line and a control system in communication with the detector and the product tank fill valve, along with certain algorithms, to adjust by an iterative process, the product discharge time, thereby maximizing resin fill in the product tank and minimizing the lost reactor gas volume.

Abstract: A method for controlling a solution process for the polymerisation of olefins is disclosed. The method is based on an algorithm that calculates predicted operating parameters of the process, including calculation of the extent of reaction (?), as a function of the solution density (?), and then calculation of the whole composition of the solution. The algorithm resolves a system of equations comprising the equation of state in the PC-SAFT form, the Lewis-Mayo equation for monomer incorporation into a copolymer, and the stoichiometry equation. Predicted parameters are compared to target parameters to detect possible deviations and implement corresponding compensation in the feed.

Abstract: A method for controlling a transition from an initial polymerization reaction to a target polymerization reaction in a manner that reduces significantly the amount of off-grade product having excessively low density produced during the transition, including steps of: during the transition, maintaining a first one of a concentration ratio and a feed ratio at an at least substantially constant value while implementing process changes in an effort to bring produced polymer into compliance with a target specification set and monitoring (without controlling) the other one of the concentration ratio and the feed ratio to generate first data; and during the transition, determining from the first data whether polymer having excessively low density is likely to be produced during the transition, and upon determining that polymer having excessively low density is likely to be produced during the transition, maintaining during the remaining portion of the transition the other ratio at a value that is at least substantia

Abstract: A multiple stage apparatus and process using aerodynamic reactors and aero-coalescers in sequence for the selective capture and removal of purified carbon dioxide gas, the sequential capture and removal of mercury, metal and particulate aerosols by a recycling chemical generation-regeneration system using alkali metal chloride solution following multiple oxidations of mercury vapor, and nitric oxide in sequence, selective capture and removal of sulfur dioxide and nitrogen dioxide by two stage absorption by a recycling chemical generation-regeneration system using alkali metal hydroxide-carbonate-bicarbonate solution together with sequential oxidation to alkali metal sulfate and alkali metal nitrate compounds through evaporation and crystallization. Carbon dioxide capture and recovery is achieved in sequence by selective thermal decarbonation from an alkaline liquid followed by recovery as a purified gas stream.

Abstract: The present invention relates to a method for performing a polymerization process in a stirred reactor, wherein a critical time window is determined by means of a monitor of at least one polymerization process parameter and an associated process window, and when a critical time window is present, an adaptation of process conditions is made in order to configure the polymerization process to conform to the process window.

Abstract: The present invention is directed to various methods and systems for detecting at least one impurity in a bulk fluid. In certain embodiments, the methods are performed in conjunction with a polymerization reactor system such as a gas-phase reactor system.

Abstract: A method for controlling sheeting in a gas phase reactor that includes producing a polyolefin with at least one metallocene catalyst and at least one static control agent in at least one gas phase reactor, measuring entrainment static using a static probe, and adjusting the concentration of the static control agent in response to changes in the measured entrainment static is disclosed.

Abstract: A method for the control of a polymerization process, which method employs the combination of a densitometer measurement of the polymerization reaction mixture and a quadratic computer model.

Abstract: Disclosed herein is an optimization method in a polymerization system in which heat is generated during the polymerization with an initiator.

Abstract: In some embodiments, a method including the steps of: during a polymerization reaction producing a polymer resin in a fluid bed reactor, measuring reaction parameters including at least reactor temperature, at least one property of the resin, and amount of at least one condensable diluent gas in the reactor; determining from at least one measured resin property using a predetermined correlation, a dry melt initiation temperature value for a dry version of the polymer resin; and during the reaction, using a melt initiation temperature depression model to determine in on-line fashion a reduced melt initiation temperature for the resin (e.g., a temperature at which the resin is expected to begin to melt) in the presence of the at least one condensable diluent gas in the reactor.

Abstract: A method for monitoring a polymer resin-producing polymerization reaction in a fluid bed reactor, including by determining in on-line fashion a maximum diluent (e.g., ICA) concentration and an optimal diluent (e.g., ICA) concentration in the reactor, whereby performing the reaction with diluent (e.g., ICA) concentration less than the maximum diluent concentration ensures an acceptably low risk that the resin in the reactor in the presence of condensable diluent gas will reach a condition of limiting stickiness. Preferably, the optimal diluent concentration maximizes production rate subject to relevant constraints. The method can also include at least one of the steps of controlling the reaction to achieve a desired production rate by controlling diluent (e.g.

Abstract: The present technique provides for the use of spectroscopic probes, such as Raman probes, within the conduits or other equipment of a polyolefin production system and upstream systems. The Raman probe or other spectroscopic probes may be used to obtain spectroscopic measurements of the contents of the conduits or other equipment. The spectroscopic measurements may be processed and analyzed to determine one or more properties of interest of the contents.

Abstract: A method for controlling a transition from an initial polymerization reaction to a target polymerization reaction in a manner that reduces significantly the amount of off-grade product having excessively low density produced during the transition, including steps of: during the transition, maintaining a first one of a concentration ratio and a feed ratio at an at least substantially constant value while implementing process changes in an effort to bring produced polymer into compliance with a target specification set and monitoring (without controlling) the other one of the concentration ratio and the feed ratio to generate first data; and during the transition, determining from the first data whether polymer having excessively low density is likely to be produced during the transition, and upon determining that polymer having excessively low density is likely to be produced during the transition, maintaining during the remaining portion of the transition the other ratio at a value that is at least substantia

Abstract: Methods and system for in-situ measurement of polymer growth within an olefin polymerization reactor are provided. The method includes polymerizing one or more olefins within a reactor at a first temperature sufficient to deposit a polymer coating therein. A second temperature is created within the reactor, and a rate of temperature change is measured from the first temperature to the second temperature. The rate of temperature change is correlated to a thickness of the polymer coating deposited within the reactor.

Abstract: A process for increasing a granular particle density of a polymeric product using at least one particle density promoting agent is described. The process includes passing a gaseous stream comprising at least one monomer through a fluidized bed reactor in the presence of a catalyst to form a polymeric product having a first granular particle density of less than or equal to about 850 kg/m3, contacting the polymeric product with at least one particle density promoting agent to increase the granular particle density of the polymeric product by at least 2%, withdrawing the polymeric product having an increased granular particle density and a recycle stream comprised of unreacted monomers, and cooling and reintroducing the recycle stream into the fluidized bed reactor with sufficient additional monomer to replace the monomer polymerized and withdrawn as the polymeric product.

Abstract: The present invention relates to a process for controlling the gas-phase co-polymerisation of olefins in a fluidised bed reactor. The present invention further relates to a method for the continuous gas-phase (co-)polymerisation of olefins in a fluidised bed reactor in the presence of a polymerisation catalyst wherein the density SPAN of the polymer powder particles leaving the reactor is maintained below certain values throughout the polymerisation.

Abstract: In some embodiments, a method including the steps of monitoring a polymerization reaction which produces a polymer resin in a fluid bed reactor, where a dry melt reference temperature is characteristic of melting behavior of a dry version of the resin, and in response to data indicative of at least one monitored parameter of the reaction, determining a reduced melt reference temperature that is at least substantially equal to the difference between the dry melt reference temperature and a temperature by which the dry melt reference temperature is depressed by the presence of condensable diluent gas with the resin in the reactor. Optionally, the method also includes the step of controlling the reaction in response to the reduced melt reference temperature or a stickiness parameter determined from the reduced melt reference temperature.

Abstract: Embodiments of our invention relate generally to methods of monitoring and controlling polymerization reactions including reactions producing multimodal polymer products using multiple catalysts in a single reactor. Embodiments of the invention provide methods of rapidly monitoring and controlling polymerization reactions without the need to sample and test the polymer properties. The method uses reactor control data and material inventory data in a mathematical leading indicator function to control the reactor conditions, and thereby the products produced under those conditions.

Abstract: Multiple components are selected, conveyed, and measured in a polymerization system. A control system adjusts the system variables to the desired values. Portions of the components can be fed to a pre-contactor before introduction into the polymerization reactor. The catalyst component concentrations and residence times are tightly controlled in the pre-contactor to affect product properties. The pre-contactor can be a single or multiple combinations of a CSTR or plug flow pre-contactors.

Abstract: A method of monitoring the evolution of polymer and/or colloid stimuli responsiveness during synthesis of polymers and/or colloids, including postpolymerization modifications on natural and synthetic polymers, includes providing a reactor in which the polymers and/or colloids are synthesized; and providing a means of monitoring the stimuli responsiveness of the polymers and/or colloids during said synthesis. Preferably, the method also includes monitoring the evolution of the characteristics of the polymers and/or colloids during said synthesis. Preferably, evolution of polymer and/or colloid stimuli responsiveness is correlated to the evolution of the properties of the polymers and/or colloids themselves. Also, preferably the conditions of the fluid in the reactor in which the synthesis occurs is determined. The determination can be by detection, choice of materials and temperature conditions, for example, and combinations thereof.

Abstract: A process for controlling a continuous gas phase exothermic process in a reactor comprising: (i) effecting a gas phase exothermic reaction under a set of operating conditions in the presence of a cooling agent, the cooling agent having a pre-selected concentration and feed rate of an induced cooling agent; (ii) determining a maximum production rate (I) without regard to limitations due to the cooling agent under the operating conditions; (iii) determining a maximum production rate (II) with regard to limitations due to the cooling agent under the operating conditions; (iv) calculating an optimal concentration of the induced cooling agent such that the difference between (I) and (II) is minimized; and (v) adjusting the feed rate of the induced cooling agent to achieve the concentration value calculated in (iv).

Abstract: A method for the control of a polymerization process, which method employs the combination of a densitometer measurement of the polymerization reaction mixture and a quadratic computer model.

Abstract: A large-scale and efficient industrialization of olefin polymerization by metallocene catalysts is realized by, in olefin polymerization by metallocene-based catalysts, increasing catalytic activity and polymerization efficiency to sufficiently bring out the performances of the metallocene catalysts and maintain a stable polymerization reaction. The amount of a halogen-containing compound is controlled so that the gram-atomic amount ratio to a transition metal of a halogen atom in a halogen-containing compound in solvents and materials other than a halogen atom in a catalyst component is 0.8 or less, in manufacturing plants of commercial level in an olefin polymerization by a metallocene catalyst.

Abstract: The present invention provides a polymer composite membrane having a polymer membrane and a poly(furfuryl alcohol) filling internal pores of the polymer membrane. The polymer composite membrane can have a high proton conductivity and/or a reduced methanol permeability and can be used in fuel cells, electrochemical sensor, and the like. The present invention also provides a method of making a polymer composite membrane, by providing a perfluorosulfonic polymer member, subjecting the perfluorosulfonic polymer member to a furan-based monomer, and polymerizing the furan-based monomer to obtain a polymer composite membrane having a high proton conductivity and/or a reduced methanol permeability.

Abstract: The present technique provides for the use of spectroscopic probes, such as Raman probes, within the conduits of a polyolefin production system. The Raman probe or other spectroscopic probes may be used to obtain spectroscopic measurements of the contents of the conduits. The spectroscopic measurements may be processed and analyzed to determine the composition of the conduit contents. In addition, the spectroscopic measurements may be used in conjunction with correlations or other statistical models to determine one or more properties of interest of a constituent of the conduit contents. One or more processes upstream and/or downstream of the conduit may be adjusted in response to the determined composition or composition properties.

Abstract: The present technique provides for the use of spectroscopic probes, such as Raman probes, within the conduits of a polyolefin production system. The Raman probe or other spectroscopic probes may be used to obtain spectroscopic measurements of the contents of the conduits. The spectroscopic measurements may be processed and analyzed to determine the composition of the conduit contents. In addition, the spectroscopic measurements may be used in conjunction with correlations or other statistical models to determine one or more properties of interest of a constituent of the conduit contents. One or more processes upstream and/or downstream of the conduit may be adjusted in response to the determined composition or composition properties.

Abstract: Disclosed is process for producing polyethylene using a slurry loop reactor. The process includes using a mathematical model to predict a plurality of process control parameters based on the desired product properties and reactor characteristics and controlling the process using the predicted process control parameters. Also disclosed is a process controller programmed with the model and a method for optimizing the configuration of a loop reactor using the model.

Abstract: The present technique provides for the use of spectroscopic probes, such as Raman probes, within the conduits of a polyolefin production system. The Raman probe or other spectroscopic probes may be used to obtain spectroscopic measurements of the contents of the conduits. The spectroscopic measurements may be processed and analyzed to determine the composition of the conduit contents. In addition, the spectroscopic measurements may be used in conjunction with correlations or other statistical models to determine one or more properties of interest of a constituent of the conduit contents. One or more processes upstream and/or downstream of the conduit may be adjusted in response to the determined composition or composition properties.

Abstract: Nanoscale molecularly imprinted polymers (MIP) having polymer features wherein the size, shape and position are predetermined can be fabricated using an xy piezo stage mounted on an inverted microscope and a laser. Using an AMF controller, a solution containing polymer precursors and a photo initiator are positioned on the xy piezo and hit with a laser beam. The thickness of the polymeric features can be varied from a few nanometers to over a micron.

Abstract: The present invention relates to methods for controlling fouling in the reaction zone of slurry-type olefin polymerization reactors by measuring a process operating parameter and by responding to said process operating parameter, e.g., by introducing a gaseous poison for the polymerization catalyst in response to a comparison between said measured parameter and a fouling parameter limit for said measured parameter.

Abstract: Embodiments of the invention provide a method of controlling a gas-phase polymerization process. The method includes determining a difference between a control variable of the polymerization process, such as the production rate, and the desired value of the control variable; adjusting or maintaining a first manipulated variable to at least partially compensate for the difference between the control variable and the desired value; and adjusting or maintaining a second manipulated variable to at least partially compensate for the effect of adjusting or maintaining the first manipulated variable.

Abstract: In some embodiments, a method for determining initial conditions for a transition from an initial reaction to a target reaction to minimize (or substantially minimize) the amount of off-grade material produced during the transition, and optionally also process control variables for implementing the transition. Some embodiments also include the steps of setting the reaction conditions to determined initial conditions and then implementing the transition.

Abstract: The invention relates to water-soluble, preferably powder-form polymer compositions which are obtained by continuous polymerization of at least one unsaturated monomer. At least one parameter that influences the polymerization is varied according to a recurrent pattern. The invention also relates to the use of the inventive polymer compositions and to a method for producing them.

Abstract: The present invention relates to a process for improving the start up of polymerization or copolymerization of ethylene in a gas phase reactor, preferably a fluidized bed gas phase reactor.

Abstract: The present invention discloses a method for controlling the onset and development of swelling in a slurry loop reactor by progressively diluting the reactor, the amount of dilution being driven by the amplitude of the fluctuations measured on some plant measurement.

Abstract: This invention relates to a process for maintaining heat transfer capacity of a cycle cooler while polymerizing olefin(s) in the presence of catalyst and a carboxylate metal salt by controlling the amount of carboxylate metal salt present in the reaction system. In particular, the invention relates to maintaining a cycle cooler performance parameter substantially constant while polymerizing olefin(s) in the presence of a carboxylate metal salt and a conventional-type transition metal polymerization catalyst compound, or a metallocene-type polymerization catalyst compound. This invention further relates to a process wherein the cycle cooler performance parameter is a heat transfer capacity of the cycle cooler, a pressure drop across the cooler, or a cooler approach temperature of a cycle cooler.