Abstract: Disclosed herein is a device and method for changing the conditions of a solution flowing in a serial path. In particular, disclosed herein is a device that includes a chemical reactor, a first system, and a second system that are each serial to one another. Each of the first system and the second system include a mixing chamber, a solvent reservoir, a solvent pump, and one or more detectors. Also disclosed herein is a method for changing the condition of a solution that includes flowing a liquid sample in a path, serially mixing the sample with at least two discrete solvents while it flows through the path, and detecting the condition of the sample after it is mixed with each solvent.

Abstract: An arrangement for measuring a volume of a solid or liquid sample includes a first chamber for accommodating the sample; at least one second chamber connectable to the first chamber; a third chamber connectable to a gas supply source and connected to a gas entry path leading to at least one of the first chamber and the second chamber; a pressure sensor; plural gas paths comprising plural valves; a temperature equalization system configured to temper at least the first chamber, the second chamber and the third chamber to substantially a same temperature, wherein the gas paths and the valves are arranged and connected such as to allow, filling gas out of the third chamber into at least one of the first chamber and the second chamber, and measuring a pressure in at least one of the first chamber and the second chamber.

Abstract: This disclosure provides for polymerization processes of polyolefins wherein the melt index can be regulated. For example, there is provided a process for producing a polyethylene, the process comprising: (1) in a polymerization reactor, contacting (a) a polymerization catalyst, (b) ethylene, (c) an optional ?-olefin comonomer, and (d) (x+y) ppm by weight of an antistatic agent on an ethylene basis; and (2) applying reaction conditions to the reaction mixture suitable to produce the polyethylene having a desired set of characteristics, such as desired target melt index. The disclosed polymerization processes allow for production of polyolefins having higher melt indices, and in the alternative to produce polyolefins having a desired target melt index at lower polymerization temperatures.

Abstract: A system and method for feeding a chromium-based catalyst to a polymerization reactor; adding a reducing agent to the chromium-based catalyst, and polymerizing an olefin into a polyolefin in the polymerization reactor in the presence of the chromium-based catalyst.

Abstract: The invention relates to an apparatus for producing pulverulent poly(meth)acrylate, comprising a reactor for droplet polymerization having an apparatus for dropletization of a monomer solution for the preparation of the poly(meth)acrylate having holes through which the monomer solution is introduced, an addition point for a gas above the apparatus for dropletization, at least one gas withdrawal point on the circumference of the reactor, a fluidized bed and an apparatus for product discharge from the fluidized bed. The apparatus for product discharge comprises a discharge apparatus, with a backup segment (39) disposed above the discharge apparatus.

Abstract: Process for the preparation of a polyolefin in a reaction system comprising a reactor comprising a fluidized bed and a distribution plate, product purge bin, and granular feed bin, wherein the process comprises feeding a polymerization catalyst to the fluidized bed, feeding ?-olefin monomer(s) to the reactor, circulating fluids from the top of the reactor to the bottom of the reactor, withdrawing a stream comprising the polyolefin and fluids from the reactor and passing said stream into the product purge bin, purging the product purge bin with a purge stream comprising an inert gas to obtain a stream comprising a purged polyolefin and a stream comprising fluids, introducing part of the stream comprising fluids back into the reactor, introducing the stream comprising the purged polyolefin into the granular feed bin, and contacting a deactivating stream with purged polyolefin in granular feed bin to obtain the polyolefin free of polymerization catalyst.

Abstract: A system and method of gas-displacement volumetry uses a pressure differential between two chambers of known volumes in order to calculate the volume of an object placed inside one of the chambers. The process involves measuring the pressures of a gas within two sealed chambers with one of the chambers containing an object, equalizing the pressure in the two chambers and using the equilibrium pressure, as well as the two initial pressures, to form a ratio between the free volumes of these chambers. From the pressure differentials and ratios of free volumes, the volume of the object can be determined. The system and method can be automated and controlled through the use of computers, sensors and controls. The system and method can be used to accurately determine the volume of irregular objects.

Abstract: A method for monitoring a chromatograph used to control production of a chemical product. The method involves sampling a chemical mixture of chemical components used during the production to form the chemical product, measuring the composition of the sample with a chromatograph and adjusting the amount of the chemical components based on the measured composition. The method also involves measuring actual parameters of the sample with at least one gauge, determining expected parameters of the sample based on the measured composition and the measured actual parameters using an equation-of-state, and detecting a fault in the chromatograph by comparing the expected parameters with the actual parameters.

Abstract: Polymerization reactor systems providing integrated liquid-solid sampling systems are disclosed. Methods for operating such polymerization reactor systems and for measuring a property of the liquid portion of liquid-solid mixture are described.

Abstract: Processes of forming polyolefins are described herein. One or more specific embodiments of the processes generally include introducing olefin monomer selected from C2-C3 olefins into a first reaction zone under first polymerization conditions to form a first polyolefin; withdrawing a transfer effluent from the first reaction zone, the transfer effluent including first polyolefin and unreacted olefin monomer; introducing the transfer effluent, a comonomer selected from C4-C8 olefins, and additional olefin monomer to a second reaction zone under second polymerization conditions to form a second reactor product; maintaining an essentially constant comonomer:olefin monomer ratio in the second reaction zone; and withdrawing at least a portion of the second reactor product, wherein the second reactor product includes a bimodal polyolefin.

Abstract: The invention relates to a process for preparing a semi-aromatic polyamide from diamine and dicarboxylic acid, comprising steps of •(i) dosing a liquid diamine to an agitated powder comprising an aromatic dicarboxylic acid thereby forming a powder comprising a diamine/dicarboxylic acid salt (DD-salt), and •(ii) solid-state polymerizing the DD-salt to obtain the polyamide.

Abstract: Methods and systems for controlling a polymerization reaction in a non-sticking regime are disclosed. An exemplary method includes measuring parameters for the polymerization reaction including a reactor temperature and a concentration of an induced condensing agent (ICA) in a polymerization reactor. An equivalent partial pressure ((PICA)equiv) of the ICA is calculated. The polymerization reaction is located in a two dimension space defined by a reactor temperature dimension and a ((PICA)equiv) dimension. The location in the two dimensional space is compared to an non-sticking regime, defined as the space between an upper temperature limit (UTL) curve and a lower temperature limit (LTL) curve. The parameters of the polymerization reaction are adjusted to keep the polymerization reaction within the non-sticking regime.

Abstract: Polymerization reactor systems providing integrated liquid-solid sampling systems are disclosed. Methods for operating such polymerization reactor systems and for measuring a property of the liquid portion of liquid-solid mixture are described.

Abstract: A process sends at least a portion of an oligomerization feed to a first oligomerization reactor zone that includes a zeolite or a SPA catalyst and another portion of the same feed to a second oligomerization reactor zone that includes an amorphous silica alumina catalyst. The first oligomerization reactor zone makes aliphatic olefins that can be cracked to propylene and the second oligomerization reactor zone makes cyclic molecules that can be converted to aromatics in an FCC unit.

Abstract: A method is described that includes contacting an olefin with a catalyst in a polymerization reactor, polymerizing at least a portion of the olefin to form an alpha olefin reaction product, detecting a condition within the polymerization reactor, determining an average temperature of at least one olefin product particle based on the condition, determining an operating particle temperature threshold using a foul curve, comparing the average temperature of the polymer particle to the operating particle temperature threshold, changing one or more operating parameters in response to the comparing, and maintaining the average temperature of the olefin polymer particle at or below the operating particle temperature threshold in response to changing the one or more operating parameters. The alpha olefin reaction product includes a plurality of olefin polymer particles, and the polymerization reactor includes a reaction mixture that includes the olefin, the catalyst, a diluent, and the alpha olefin reaction product.

Abstract: The present invention relates to a method to control a liquid feed stream carried out by measuring at least one spectrum of the liquid feed stream comprising an initiator or catalyst, determining its activity using a predictive model on the basis of said spectrum and adjusting the feed streams and/or the preparation conditions of the feed stream comprising the initiators or catalysts in order to attain or maintain a desired level of total activity.

Abstract: Method for controlling a process for the production of a polymer by polymerization of a monomer and a comonomer. The process includes maintaining a substantially constant effective flow ratio (EFR), the effective flow ratio being defined as EFR=(Qcomo?Lcomo)/(Qmono?Lmono), Qcomo and Qmono being, respectively, flow rates of comonomer and monomer to the reactor, Lcomo and Lmono being, respectively, losses of comonomer and monomer.

Abstract: In a process for producing polyamides by polycondensation of polycondensable polyamide-forming monomers and/or oligomers in reaction mixtures comprising same, which may be water-containing but are free from organic solvents, the polycondensation is effected in an agitated reactor under agitation in a first step in the liquid phase and after a phase change taking place during the process in the same reactor is effected in a subsequent second step in the solid state, wherein the temperature in the reactor is below the melting point of the polyamide in the second step at least.

Abstract: Processes of forming polyolefins are described herein. One or more specific embodiments of the processes generally include introducing olefin monomer selected from C2-C3 olefins into a first reaction zone under first polymerization conditions to form a first polyolefin; withdrawing a transfer effluent from the first reaction zone, the transfer effluent including first polyolefin and unreacted olefin monomer; introducing the transfer effluent, a comonomer selected from C4-C8 olefins, and additional olefin monomer to a second reaction zone under second polymerization conditions to form a second reactor product; maintaining an essentially constant comonomer:olefin monomer ratio in the second reaction zone; and withdrawing at least a portion of the second reactor product, wherein the second reactor product includes a bimodal polyolefin.

Abstract: Polymerization reactor systems providing real-time control of the average particle size of catalyst system components are disclosed. Methods for operating such polymerization reactor systems also are described.

Abstract: The condition of internal or hidden material layers or interfaces is monitored and used for control of a process that changes a condition of a material system. The material system has multiple component materials, such as layers or embedded constituents, or can be represented with multiple layers to model spatial distributions in the material properties. The material condition changes as a result of a process performed on the material, such as by cold working, or from functional operation. Sensors placed proximate to the test material surface or embedded between material layers are used to monitor a material property using magnetic, electric, or thermal interrogation fields. The sensor responses are converted into states of the material condition, such as temperature or residual stress, typically with a precomputed database of sensor responses.

Abstract: Methods for controlling the weight ratio of a higher molecular weight component to a lower molecular weight component of an olefin polymer are disclosed. This weight ratio can be increased as polymerization reaction temperature and/or catalyst system residence time are increased.

Abstract: Techniques are provided for operating a reactor during a catalyst transition period. The instantaneous reaction rate during a catalyst transition period can be determined using real-time measured process variables, and material balance calculations to provide an instantaneous reaction rate in approximately real time. According to certain embodiments, a material balance can be performed on the reactor system using a continuous ideal stirred tank reactor to determine the fractions of each type of catalyst that are present in the reactor, as well as the overall weight percent of catalyst in the reactor. A controller can then calculate the overall instantaneous reaction rate based on the respective catalyst fractions and the overall weight percent of catalyst in the reactor. The catalyst feed rate can then be adjusted based on the determined instantaneous reaction rate to maintain the instantaneous reaction rate within desired limits during a catalyst transition period.

Abstract: A control method for controlling a fluidized bed polymerization reactor in the production of a given polymer product, the method comprising the following steps: (a) determining a ratio of the production rate of the polymer product in the reactor to the pressure in the reactor, (b) setting a production rate of the polymer product in the reactor which production rate, on the basis of said ratio of step (a), corresponds to a desired pressure in the reactor; (c) adjusting the feed rates of monomers into the reactor in accordance with said set point production rate.

Abstract: The invention relates to a process for operating a mixing kneader, comprising one or more shafts on whose surfaces are disposed kneading bars and which are surrounded by a casing, comprising the following steps: (a) supplying reactants at an addition site in the mixing kneader, (b) converting the reactants in an exothermic reaction, the reaction at first forming a coherent kneadable intermediate, (c) tearing and dividing the coherent kneadable intermediate to form a product, the exothermic reaction optionally continuing during the tearing and division, (d) withdrawing the product at a withdrawal site in the mixing kneader, wherein at least one of the shafts and/or the casing is heated to a temperature above 20° C. during the operation of the mixing kneader.

Abstract: Techniques are provided for operating a reactor during a catalyst transition period. The instantaneous reaction rate during a catalyst transition period can be determined using real-time measured process variables, and material balance calculations to provide an instantaneous reaction rate in approximately real time. According to certain embodiments, a material balance can be performed on the reactor system using a continuous ideal stirred tank reactor to determine the fractions of each type of catalyst that are present in the reactor, as well as the overall weight percent of catalyst in the reactor. A controller can then calculate the overall instantaneous reaction rate based on the respective catalyst fractions and the overall weight percent of catalyst in the reactor. The catalyst feed rate can then be adjusted based on the determined instantaneous reaction rate to maintain the instantaneous reaction rate within desired limits during a catalyst transition period.

Abstract: The present invention provides a method to calibrate a NIR analyzer to measure monomer concentrations at one or more locations in a reactor system. The regression coefficients for the NIR analyzer are transferable between reactors using the same process (solution polymerization to solution polymerization) and may be used to control the reaction, or calibrate flow meters on line.

Abstract: A process for continuously producing water-absorbing polymer particles, wherein the monomer stems from at least two different sources and the monomer from one source differs from the monomer from at least one other source in the content of at least one secondary component.

Abstract: A method for the copolymerization of ethylene and a C3+ olefin in a loop reactor and polymers formed therefrom are described herein. The method generally includes introducing an ethylene monomer, a C3+ olefin and a diluent carrier liquid into a loop reactor. A catalyst system can be supplied to said loop reactor. The diluent liquid, ethylene monomer, and C3+ olefin can be circulated through said loop reactor, while copolymerizing said ethylene and C3+ olefin in the presence of said catalyst system to produce a slurry. The slurry can be diverted into a settling leg, and sequentially discharged therefrom and withdrawn from said loop reactor. An ethylene monomer co-feed can be introduced into said loop reactor at spaced locations downstream of the ethylene and diluent. The ethylene co-feed can be introduced in an amount effective to reduce the variation in the ratio of ethylene and C3+ olefin.

Abstract: Methods and systems for preparing catalyst, such as chromium catalysts, are provided. The valence of at least a portion of the catalyst sent to an activator is changed from Cr(III) to Cr(VI). The catalyst is prepared or activated continuously using a fluidization bed catalyst activator.

Abstract: Provided is a method for operating a gas-phase, fluidized-bed reactor. The method has the steps of (a) receiving a signal from a probe in contact with the interior of the reactor or a process component in communication with the reactor, wherein the signal is derived from a physical property or condition within the reactor or the process component; (b) modifying the signal to create a modified signal; and (c) adjusting one or more operating parameters of the reactor in response to the modified signal if the physical property or condition is different than a desired value. There is also a method for reducing fouling in a distributor plate of a gas-phase, fluidized-bed reactor with a recycle line.

Abstract: A system and method for discharging a transfer slurry from a first polymerization reactor through a transfer line to a second polymerization reactor, the transfer slurry including at least diluent and a first polyethylene. A product slurry is discharged from the second polymerization reactor, the product slurry including at least diluent, the first polyethylene, and a second polyethylene. The velocity, pressure drop, or pressure loss due to friction in the transfer line is determined, and a process variable adjusted in response to the velocity, pressure drop, or pressure loss not satisfying a specified value.

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: Polymerization reactor systems providing real-time control of the average particle size of catalyst system components are disclosed. Methods for operating such polymerization reactor systems also are described.

Abstract: There are disclosed a regenerated rubber, a method and apparatus for obtaining regenerated rubbers from vulcanized crumb rubber, such as rubber from scrap. The apparatus is a thermokinetic mixer having the particularity to have an air tight stationary chamber with inner non-uniform surface. The method comprises the steps of raising the speed of the rotor shaft in order to increase a temperature of a mixture made of vulcanized crumb rubber and a lubricant, such as oil, until a devulcanizing temperature is reached; and reducing the temperature of the mixture to a lower temperature during a second period of time. The method of the invention is environmentally friendly or “green”, since the regeneration method does not use chemicals, includes a shorter period of treatment at higher temperature avoiding the risks of rubber cracking and spontaneous combustion, and further allowing mass-production of regenerated rubber with lower energy consumption.

Abstract: The present invention relates to a method to control a liquid feed stream carried out by measuring at least one spectrum of the liquid feed stream comprising an initiator or catalyst, determining its activity using a predictive model on the basis of said spectrum and adjusting the feed streams and/or the preparation conditions of the feed stream comprising the initiators or catalysts in order to attain or maintain a desired level of total activity.

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: Catalyst deactivating agents and compositions containing catalyst deactivating agents are disclosed. These catalyst deactivating agents can be used in methods of controlling polymerization reactions, methods of terminating polymerization reactions, methods of operating polymerization reactors, and methods of transitioning between catalyst systems.

Abstract: The disclosure relates to a device for removing and analyzing a sample from a polymerization reactor including one or more sample conduits for removing a sample from the reactor and transferring the sample to a sample flash tank, whereby the conduits are in communication with the reactor and are provided with at least two sampling valves; a sample flash tank for separating said solid particles and evaporated gas, whereby the sample flash tanks are connected to the conduits and provided with a device for analyzing evaporated gas, and including a sample receiver for purifying the solid particles. The receivers are connected to the sample flash tanks and provided with an apparatus for analyzing the solid particles. The disclosure includes a method for improving a polymerization reaction.

Abstract: The present invention provides a method for production of a copolymer for photoresists in which the bias of the monomer composition ration is small. This method for production is a method for production of a copolymer for photoresists, which copolymer containing at least two types of repeating units, the method having a supplying step of supplying a monomer solution and a solution containing a polymerization initiator into a polymerization reaction system, wherein the range of fluctuation of the monomer composition ratio of unreacted monomers is within the range between minus 15% and plus 15% or the standard deviation of the monomer composition ratio of unreacted monomers is within 2 in the polymerization reaction system during the period from the start of the polymerization reaction to the end of supplying of the monomer solution.

Abstract: Methods for removing polymer skins or build-up from reactor walls in polymerization reactor systems containing a loop slurry reactor are disclosed. Such methods can employ removing some or all of the comonomer from the reactor system in combination with increasing the polymerization temperature of the loop slurry reactor.

Abstract: Methods and systems for preparing catalyst, such as chromium catalysts, are provided. The valence of at least a portion of the catalyst sent to an activator is changed from Cr(III) to Cr(VI). The catalyst is prepared or activated continuously using a fluidization bed catalyst activator.

Abstract: Generally, a method of monitoring a polymerization reaction in a fluid bed reactor to generate, in on-line fashion, data indicative of the imminent occurrence of a discontinuity event (for example, sheeting) and optionally also control the reaction to prevent the occurrence of the discontinuity event is provided. Typical embodiments include the steps of generating in on-line fashion at least one of bed static data indicative of static charge in the fluidized bed and carryover static data indicative of carryover static; and generating at least one of temperature data (in on-line fashion using at least one monitored reaction parameter) indicative of a first temperature and acoustic emission data indicative of resin stickiness in the reactor, where the first temperature is indicative of at least one of degree of resin stickiness in the reactor and a characteristic of melting behavior of polymer resin in the reactor in the presence of at least one diluent.

Abstract: Provided is 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 provides methods 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. The first and second manipulated variables can include process variables such as the fluidized bed weight, the catalyst concentration, the concentration of one or more monomers, the flow of one or more comonomers, the ratio of one comonomer to another comonomer, the activator concentration, the ratio of an activator to selectivity control agent, the concentration of a chain transfer agent, and the retardant concentration.

Abstract: This invention is related to the field of olefin polymerisation in double loop reactors and especially to the polymerisation of olefins with very active catalyst systems. It discloses a method for reducing blockage when transferring polymer product from the first loop to the second loop of a double loop reactor.

Abstract: A process for polymerizing one or more olefins in a gas-phase polymerization reactor is provided. The gas-phase reactor has a fluidized bed and a fluidizing medium. The fluidizing medium has an operating density and an operating velocity. The process includes determining a critical gas velocity and/or determining a critical gas velocity for the polymerization. The operating gas density and/or the operating gas velocity for the fluidizing medium is then adjusted to be less than or equal to its respective critical value. The process includes increasing the bulk density of the fluidized bed. The increase in the fluidized bed bulk density increases productivity without increasing reactor residence time.

Abstract: Techniques are provided for operating a reactor during a catalyst transition period. The instantaneous reaction rate during a catalyst transition period can be determined using real-time measured process variables, and material balance calculations to provide an instantaneous reaction rate in approximately real time. According to certain embodiments, a material balance can be performed on the reactor system using a continuous ideal stirred tank reactor to determine the fractions of each type of catalyst that are present in the reactor, as well as the overall weight percent of catalyst in the reactor. A controller can then calculate the overall instantaneous reaction rate based on the respective catalyst fractions and the overall weight percent of catalyst in the reactor. The catalyst feed rate can then be adjusted based on the determined instantaneous reaction rate to maintain the instantaneous reaction rate within desired limits during a catalyst transition period.

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 in on-line fashion 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: The invention relates to a device for taking out and analyzing a sample from a polymerization reactor comprising one or more sample conduits (2), for taking a sample out of said reactor and for conducting said sample to one or more sample flash tanks (3), whereby said conduits each are in communication with said reactor (19) and each are provided with at least two sampling valves (4, 5); comprising one or more sample flash tanks (3), for separating said solid particles and evaporated gas, whereby said sample flash tanks are connected to said conduits (2) and provided with means for analyzing said evaporated gas (7), and comprising one or more sample receivers (6), for purifying said solid particles, whereby said receivers are connected to said sample flash tanks (3) and provided with means (8) for analyzing said solid particles. The invention further relates to a method for improving a polymerization reaction in a polymerization reactor.