Abstract: In the present invention the NonRandom Two-Liquid segment activity coefficient model system of the parent application is extended for computation of ionic activity coefficients and solubilities of electrolytes, organic and inorganic, in common solvents and solvent mixtures. The invention method and system may be applied to the chemical and/or pharmaceutical design process. In addition to the three types of molecular parameters defined for organic nonelectrolytes, i.e., hydrophobicity X, polarity Y, and hydrophilicity Z, an electrolyte parameter, E, is introduced to characterize both local and long-range ion-ion and ion-molecule interactions attributed to ionized segments of electrolytes. Successful representations of mean ionic activity coefficients and solubilities of electrolytes, inorganic and organic, in aqueous and nonaqueous solvents are presented.

Abstract: Method of conducting chromatography comprising controlling a retention time of one or more chemical species in a mixture by determining at least one conceptual segment of: a) the one or more chemical species, b) a mobile phase component, and c) a stationary phase component. The method further includes defining an identity and an equivalent number of each of the at least one conceptual segment.

Abstract: Included are methods for modeling at least one physical property of a mixture of at least two chemical species. One or more chemical species of the mixture are approximated or represented by at least one conceptual segment. The conceptual segments are then used to compute at least one physical property of the mixture. An analysis of the computed physical properties forms a model of at least one physical property of the mixture. Also included are computer program products and computer systems for implementing the modeling methods.

Abstract: A computer modeling apparatus and method optimize refinery operations. Included are an input module enabling user specification of inventory information including at least one rundown component, and user specification of refinery product commitments, and a processor routine executable by a computer and coupled to the input module. The processor routine, in response to the user specification, sequences refinery operations into a schedule that matches refinery commitments with inventory and unit rundown operations, wherein the refinery operations include refinery operations events, and provides on output a display of the schedule in a manner enabling optimized refinery operations.

Abstract: A computer system and method of modeling a crystallization process includes representing a plurality of crystals in a solution by different subsets of the plurality, tracking increase of the respective characteristic length of each crystal group, and determining a crystal size distribution to output a model to a user. Each subset forms a respective crystal group characterized by group attributes of (i) a number of crystals and (ii) a characteristic length. Additionally, the system and method track generation of new crystal groups generated by seeding, nucleation and/or breakage.

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: An extension of COSMO-SAC to electrolytes (eCOSMO-SAC) combines the COSMO-SAC term for short range molecule-molecule, molecule-ion and ion-ion interactions with the extended symmetric Pitzer-Debye-Hückel term for long range ion-ion interactions. The extension recognizes that like-ion repulsion and local electroneutrality govern the surface segment contacts, and introduces a dual sigma profile concept for electrolyte systems. The eCOSMO-SAC formulation predicts activity coefficients of several representative electrolyte systems.

Abstract: A method of designing or optimizing a column for a separation process includes the computer implemented steps of, in a digital processor, providing vapor-side and liquid-side mass transfer coefficient expressions and a mass transfer area expression relevant for a subject column, the vapor-side and liquid-side mass transfer coefficient expressions and the mass transfer area expression having been derived from defining a column average height equivalent to a theoretical plate HETP) as a mathematical relationship in which HETP is proportional to a vapor flow rate, is inversely proportional to effective packing area participating in mass transfer, has a first correction factor with respect to liquid-side mass transfer, and has a second correction factor with respect to vapor-side mass transfer.

Abstract: Method of conducting chromatography comprising controlling a retention time of one or more chemical species in a mixture by determining at least one conceptual segment of: a) the one or more chemical species, b) a mobile phase component, and c) a stationary phase component. The method further includes defining an identity and an equivalent number of each of the at least one conceptual segment.

Abstract: A computer modeling apparatus includes an input module enabling user specification of a subject facility design based on limited data. The subject facility design includes design alternatives, and a processor routine coupled to the input module and responsive to the user specification by forming an input data set to a rigorous simulation modeler to model the subject facility design. The rigorous simulation modeler requires input beyond the limited data. The processor routine enables execution of the simulation modeler. The computer modeling apparatus further includes an interface member that enables the production of a rigorous simulation model of the subject facility design from the simulation modeler. The subject facility is one of an oil processing facility, a gas processing facility, an oil and gas separation facility, or a chemical processing facility.

Abstract: Methods of conducting industrial manufacture, research or development. The method comprise computer-implemented steps of modeling at least one physical property of a mixture of at least two chemical species by determining at least one conceptual segment for each of the chemical species. The steps of determining at least one conceptual segment for each of the chemical species include defining an identity and an equivalent number of each conceptual segment.

Abstract: Apparatuses and methods for model quality estimation and model adaptation in multivariable process control are disclosed. A method for updating a multiple input multiple output (MIMO) dynamical model of a process includes perturbing the process, auditing the controller model, identifying poor performing submodels and re-testing the relevant process variables, re-identifying submodels and adapting the model online while the process continues to operate within normal operating parameters. An apparatus comprises an online multivariable controller, a tester, a database to store data corresponding to manipulated variables and controlled variables, and a performance diagnosis module configured to identify problematic submodels and adapt a model used by the controller.

Abstract: Methods of conducting industrial manufacture, research or development. The method comprise computer-implemented steps of modeling at least one physical property of a mixture of at least two chemical species by determining at least one conceptual segment for each of the chemical species. The steps of determining at least one conceptual segment for each of the chemical species include defining an identity and an equivalent number of each conceptual segment.

Abstract: A flood point for a packed column is determined by providing a data set of gas pressure drop values as a function of gas flow rate values at several liquid flow rates through a packed column, known flood point value for one liquid flow rate, setting flood point values for higher liquid flow rates at values lower than the known flood point value, and setting flood point values for lower liquid flow rates at values higher than the known flood point value, followed by expressing gas flow rates for liquid flow rates as fractions of the flood point value for each respective liquid flow rate.

Abstract: In the present invention the NonRandom Two-Liquid segment activity coefficient model system of the parent application is extended for computation of ionic activity coefficients and solubilities of electrolytes, organic and inorganic, in common solvents and solvent mixtures. The invention method and system may be applied to the chemical and/or pharmaceutical design process. In addition to the three types of molecular parameters defined for organic nonelectrolytes, i.e., hydrophobicity X, polarity Y, and hydrophilicity Z, an electrolyte parameter, E, is introduced to characterize both local and long-range ion-ion and ion-molecule interactions attributed to ionized segments of electrolytes. Successful representations of mean ionic activity coefficients and solubilities of electrolytes, inorganic and organic, in aqueous and nonaqueous solvents are presented.

Abstract: A computer-implemented method and system of modeling physical properties of biodiesel feedstock are presented. The invention method and system include (i) estimating values of a physical property of constituent fatty acid fragments of a mono-, di-, or triglyceride, and (ii) computing a value of the physical property of the mono-, di-, or triglyceride by expressing the value of the physical property of the mono-, di-, or triglyceride as a sum of the estimated values of the physical property of constituent fatty acid fragments thereof. The method and system further include repeating steps (i) and (ii) for different mono-, di-, and/or triglycerides, resulting in a plurality of computed values of the physical property of different mono-, di-, and triglycerides.

Abstract: In the present invention the NonRandom Two-Liquid segment activity coefficient model system of the parent application is extended for computation of ionic activity coefficients and solubilities of electrolytes, organic and inorganic, in common solvents and solvent mixtures. The invention method and system may be applied to the chemical and/or pharmaceutical design process. In addition to the three types of molecular parameters defined for organic nonelectrolytes, i.e., hydrophobicity X, polarity Y, and hydrophilicity Z, an electrolyte parameter, E, is introduced to characterize both local and long-range ion-ion and ion-molecule interactions attributed to ionized segments of electrolytes. Successful representations of mean ionic activity coefficients and solubilities of electrolytes, inorganic and organic, in aqueous and nonaqueous solvents are presented.

Abstract: Included are methods for modeling at least one physical property of a mixture of at least two chemical species. One or more chemical species of the mixture are approximated or represented by at least one conceptual segment. The conceptual segments are then used to compute at least one physical property of the mixture. An analysis of the computed physical properties forms a model of at least one physical property of the mixture. Also included are computer program products and computer systems for implementing the modeling methods.

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: Included are methods for modeling at least one physical property of a mixture of at least two chemical species. One or more chemical species of the mixture are approximated or represented by at least one conceptual segment. The conceptual segments are then used to compute at least one physical property of the mixture. An analysis of the computed physical properties forms a model of at least one physical property of the mixture. Also included are computer program products and computer systems for implementing the modeling methods.