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: In a solution polymerization process the increase in gel content in the solution at one or more locations may be detected by monitoring the structure of a spectrum obtained by analyzing the reaction at said one or more locations using a spectrometer selected from the group consisting of infrared spectrometers, near infrared spectrometers and Raman spectrometers.

Abstract: An apparatus for monitoring the polymerisation of surgical cement comprising a container for holding the surgical cement, sensing means to detect at least one environmental factor affecting surgical cement polymerisation or property of surgical cement indicating the level of polymerisation, wherein the sensing means is adapted to produce an output according to at least one environmental factor or property. The apparatus further comprises signal means to inform a user of the condition of the surgical cement according to the output of the sensing means. Suitably at least one environmental factor or property of the surgical cement is ambient temperature, ambient humidity, temperature of the surgical cement, viscosity of the surgical cement or the speed of sound through the surgical cement.

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: 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: 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: 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 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: Integrated modeling and symbolic manipulation is leveraged for the derivation, construction, maintenance, and reuse of application-independent models. Related models created for different applications share a common ancestry and maintain model consistency while enabling the models to share information about the process. Environment independent proper ancestor models (PAMs) are created for generic components of a process, such as a distillation or flash column. Models underlying an application may be comprised of various representations of multiple such processes corresponding to many different physical components. PAMs contain symbolic representations of different sub processes that occur within a process or component. A user makes assumptions about the component, by indicating how sub processes are to be considered or not considered. PAMs are then modified in accordance with the assumptions to derive a specific environment model (SEM).

Abstract: An instrument for performing highly accurate PCR employing a sample block in microtiter tray format. The sample block has local balance and local symmetry. A three zone film heater controlled by a computer and ramp cooling solenoid valves also controlled by the computer for gating coolant flow through the block controls the block temperature. Constant bias cooling is used for small changes. Sample temperature is calculated instead of measured. A platen deforms plastic caps to apply a minimum acceptable threshold force for seating the tubes and thermally isolates them. A cover isolates the block. The control software includes diagnostics. An install program tests and characterizes the instrument. A new user interface is used. Disposable, multipiece plastic microtiter trays to give individual freedom to sample tubes are taught.

Abstract: The present invention relates to a method of estimating the properties of a polymer product by using converted process variables (cPV's) which means process variable that final or intermediate product experienced earlier in average in the reactors by stage with respect to the final product, which incorporates residence time distribution to process variables, wherein said method comprises the following steps of: computing cPV's by incorporating the residence time distribution to said process variables by means of theoretically determining the amounts of content and discharge of the product in the process, and then solving the balance equations of a hypothetical substance by taking the respective process variables as those of the hypothetical substance: and estimating the properties of the product by inputting to various property estimation models cPV's in the reactors by stage with respect to the final product after incorporating the residence time distribution to said process variables.

Abstract: The present method is directed to techniques for estimating and periodically controlling the reactor split of alpha-olefin polymerizations using multiple catalysts that selectively incorporate monomers and other reactants into polymer compositions. The method provides for the rapid determination of instantaneous reactor split and cumulative split in polymerization reactors by the use of a novel linear relationship between Incorporation and Reactor Split.

Abstract: A system, method, and software to form photoresist resin which has a more uniform distribution of polymers are disclosed. In one embodiment, the method includes introducing a first monomer into a reaction vessel; introducing a second monomer into the reaction vessel; and introducing an initiator into the reaction vessel to cause a polymerization of the first and second monomers, wherein the introducing the first and second monomers into the reaction vessel is performed in a manner that a concentration ratio of the first and second monomers is a function of a predetermined inverse relationship to a reactivity ratio of the first and second monomers. In another embodiment, the method includes introducing an initiator into the reaction vessel to cause a living or pseudo-living polymerization of the first and second monomers.

Abstract: A system for controlling the temperature of a reaction mixture comprises at least one heating device for heating the mixture and a power regulator for regulating the amount of power supplied to the heating device. A controller in communication with the power regulator includes program instructions for heating the reaction mixture by setting a variable target temperature that initially exceeds a desired setpoint temperature for the mixture. When the heating device reaches a threshold temperature, the variable target temperature is decreased to the desired setpoint temperature. In another embodiment, the controller includes an adaptive control program for dynamically adjusting the duration or intensity of power pulses provided to the heating device.

Abstract: A method for providing improved estimates of properties of a chemical manufacturing process is disclosed. The method employs a process model that includes, or is modified by, scores or other gains obtained from the mathematical transformation of data obtained from an on-line analyzer. Chemical manufacturing processes using the method also are disclosed.

Abstract: Computer programs and computer-implemented methods for monitoring the progress and properties of parallel chemical reactions. The invention repeatedly receives a measured value or values associated with the contents of each of a plurality of reactor vessels and displays the measured over the course of a combinatorial chemical reaction. Reaction parameters associated with individual reactor vessels are changed in response to the value measured during the reaction. Reaction parameters include temperature, pressure, stirring speed. The reaction occurring in one or more reactor vessels is quenched in response to values measured during the reaction. The measured values are used to calculate experimental results including temperature change, pressure change, percent conversion of starting material, and viscosity. The measured values and experimental results are displayed. In another aspect, the invention features a method for controlling a combinatorial chemical reactor.

Abstract: A system for on line inference and control of physical and chemical properties of polypropylene and its copolymers is described. The system comprises models for the inference of physical and chemical properties that are not continuously measured and relevant models to control these properties as well as production rate, density of the reaction medium and other process variables of interest. The described control system allows to maximize production rate as well as catalyst yield in the producing process.

Abstract: The present invention relates to a process for maintaining a property P of a polyisobutene around a target value V during a continuous polymerisation of isobutene in a reactor containing a boiling liquid reaction phase in equilibrium with a gas phase above the said liquid phase. The process comprises continuously introducing, into the reactor, a catalyst and a C4 hydrocarbon feed and continuously withdrawing, from the reactor, the liquid reaction phase which is subsequently subjected, continuously, to at least one purification step so that to isolate the polyisobutene. The property P is chosen amongst the viscosity and the average molecular mass of the polyisobutene.

Abstract: A method for monitoring and improving the performance of a chemical manufacturing process by monitoring transients associated with the operation of process equipment located dowstream of upstream equipment is disclosed. Transients on signals such as the motor current to downstream powder feeding equipment provide early indications of changes in chemical process performance which can then be corrected by altering chemical manufacturing process conditions.

Abstract: Computer programs and computer-implemented methods for monitoring the progress and properties of parallel chemical reactions. The invention repeatedly receives a measured value or values associated with the contents of each of a plurality of reactor vessels and displays the measured over the course of a combinatorial chemical reaction. Reaction parameters associated with individual reactor vessels are changed in response to the value measured during the reaction. Reaction parameters include temperature, pressure, stirring speed. The reaction occurring in one or more reactor vessels is quenched in response to values measured during the reaction. The measured values are used to calculate experimental results including temperature change, pressure change, percent conversion of starting material, and viscosity. The measured values and experimental results are displayed. In another aspect, the invention features a method for controlling a combinatorial chemical reactor.

Abstract: An image acquisition system for machine vision systems decouples image acquisition from the transmission of the image to a host processor by using a programmable imager controller to selectively disable and enable the transmission of data to the host and by using a system of buffers to temporarily store image data pending allocation of memory. This enables the image acquisition system to acquire images asynchronously and to change the exposure parameters on a frame-by-frame basis without the latency associated with the allocation of memory for storage of the acquired image. The system architecture of the invention further permits interruption and resumption of image acquisition with minimal likelihood of missing data. Data throughput is further enhanced by transmitting to the host only that data corresponding to the region of interest within the image and discarding the data from outside of the region of interest at the camera stage.

Abstract: A constrained non-linear approximator for empirical process control is disclosed. The approximator constrains the behavior of the derivative of a subject empirical model without adversely affecting the ability of the model to represent generic non-linear relationships. There are three stages to developing the constrained non-linear approximator. The first stage is the specification of the general shape of the gain trajectory or base non-linear function which is specified graphically, algebraically or generically and is used as the basis for transfer functions used in the second stage. The second stage of the invention is the interconnection of the transfer functions to allow non-linear approximation. The final stage of the invention is the constrained optimization of the model coefficients such that the general shape of the input/output mappings (and their corresponding derivatives) are conserved.

Abstract: The present invention concerns a method of establishing synthesis paths in a multiplicity of potentially interlinkable reactions.

Abstract: The properties of a resinous material product are controlled in a manufacturing system by online process parameter monitoring and control. The online monitoring and control incorporates an in-situ measurement system that can monitor product in the process by use of a side stream ultrasonic device. The side stream device advantageously provides online real-time measures of the product's acoustical properties (e.g. velocity, attenuation) under conditions that are independent of process-stream conditions. The side stream device controls the product temperature, pressure, and flow rate while inside the side stream device and the velocity and attenuation are measured under these predetermined temperature, pressure, and flow rate conditions. The acoustical properties (e.g.

Abstract: A method for controlling the properties of the product polymer of a polymerization process to improve the process productivity and product quality in both batch and continuous production of polyamides.

Abstract: A method for controlling the properties of the product polymer of a polymerization process to improve the process productivity and product quality in both batch and continuous production of polyamides.

Abstract: An on-line optimizer is comprised of a nonlinear dynamic model (702) which is operable to provide an estimation of the output of a plant. This receives manipulated variables (MV), disturbance variables (DV), and computed disturbance variables (CDB). The estimated output of the model is then compared to the actual output measured by virtual on-line analyzer (VOA) (616). This is compared is a difference block 618 to generate a bias which is then filtered by a filter(620). The output thereof is then provided to an output block (672) in a steady state optimizer (700) to offset the desired setpoints. These set points are input to a steady state nonlinear model which is operable to optimize the inputs to the plants for use for writing new set points in accordance with a predetermined cost function. This cost function is utilized to optimize the new inputs with the use of the steady state model in accordance with various constraints and target values.

Abstract: Object services like methods or properties are provided to or inherited by objects dynamically during run-time. In one method of providing dynamic inheritance, hierarchical relationships are defined between multiple objects such that each object references or is referenced by another object. A call is made for a particular service (e.g., a method or property) at a selected object. The service is provided directly from the object whenever the service is available therefrom. Whenever the selected service is unavailable at the selected object, the call is passed to a hierarchically superior object. Another aspect of dynamic inheritance is that an object, such as the root object, may include one or more methods for adding or otherwise changing the methods or properties available from that object.

Abstract: A control method for a process of synthesis of at least one chemical product in an equipment comprising at least one reactor (R) which is assimilated to a mixed reactor, in which manipulated variables (GC) allow to act on the course of the process in order to make one or more variables related to the properties of the product and/or to the running of the process, which are called controlled variables (GR).

Abstract: A process simulator and modeling methodology employs instantaneous property measures. The instantaneous measures of various polymer properties are tracked throughout the subject polymer manufacturing system and used to calculate respective property distribution functions. For example, property distributions of composition, molecular weight, stereoregularity and long chain branching are calculated, tracked in time and location throughout the manufacturing system, and used to model the polymer manufacturing system and polymerization process performed by the system. More specifically, the present invention calculates full distribution of polymer properties from the instantaneous property measures and tracked instantaneous property distributions. This enables accurate and computationally efficient modeling of the polymerization process and manufacturing system for carrying out the same.