This paper introduces a new kind of local consistency based on the general idea of singleton arc consistency (SAC). This is a reduced form of SAC that only considers neighbourhoods of a variable with a singleton domain; hence, the name “neighbourhood SAC” (NSAC). Like AC and SAC, NSAC has a unique fixpoint, so that NSAC algorithms will produce the same result when applied to a problem regardles...

Phase equilibrium data regression is an unavoidable task necessary to obtain the appropriate values for any model to be used in separation equipment design for chemical process simulation and optimization. The accuracy of this process depends on different factors such as the experimental data quality, the selected model and the calculation algorithm. The present paper summarizes the results and...

The aim of the present paper is to identify a highly efficient binary mixture to be used in an absorptiondemixing heat transformer (ADHT) in order to make it more energy-efficient than the conventional absorption heat transformer (AHT). Firstly, 128 binary mixtures potentially interesting in terms of pure component boiling temperatures and upper critical solution temperature (UCST) were selecte...

An increasingly popular approach when solving the phase and chemical equilibrium problem is to pose it as an optimization problem. However, diiculties are encountered due to the highly nonlinear nature of the models used to represent the behavior of the uids, and because of the existence of multiple local solutions. This work shows how it is possible to guarantee-global solutions for a certain ...

Following the work of Austgen et al., the electrolyte nonrandom-two-liquid (NRTL) model was applied in a thermodynamically consistent manner to represent the vapor-liquid equilibrium (VLE) of the aqueous monoethanolamine (MEA)-CO2 system with rigorous chemical equilibrium consideration. Special attention was given to the accurate VLE description of the system at both absorbing and stripping con...

The interaction energy parameters of the Nonrandom two-liquid (NRTL) equation for Bi–Se, Pb–Se, Sb–Se, and Tl–Se binary systems were determined. difference in goodness fit between was discussed each system. activities components at corresponding temperatures four calculated using NRTL equation. mixing enthalpies Gibbs free energies these obtained. calculations are agreement with experimental da...

Isobaric vapor–liquid equilibria of the binary mixtures toluene + styrene at 30 and 40 kPa α-methylstyrene 20 25 were measured applying a recirculation still. The equilibrium data modeled adopting non-random two-liquid (NRTL) excess Gibbs energy model with RK (Redlich–Kwong) equation state. NRTL interaction parameter optimization was carried out employing own literature for system. applied corr...

Ionic liquids (ILs) have been suggested as potential "green" solvents to replace volatile organic solvents in reaction and separation processes due to their negligible vapor pressure. To develop ILs for these applications, it is important to gain a fundamental understanding of the factors that control the phase behavior of ionic liquids with other liquids. In this work, we continue our study of...

The adequate correlation of experimental phase equilibrium data by using any thermodynamic model represents a key point for the rigorous design chemical processes. However, this process remains challenging problem, due to high nonlinearity models used and consequent problems convergence. present work analyzes nonrandom two-liquids mode (NRTL) check relation between values binary interaction par...