Simultaneous process and molecular design—A property based approach

Abstract

in Wiley InterScience (www.interscience.wiley.com).Property clustering techniques and group contribution methods are combined to enable simultaneous consideration of process performance requirements and molecular property constraints. Using this methodology, the process design problem is solved to identify the property targets corresponding to the desired process performance. A significant advantage of the developed methodology is that for problems that can be satisfactorily described by only three properties, the process and molecular design problems can be simultaneously solved visually on a ternary diagram, regardless of how many molecular fragments are included in the search space. On the ternary cluster diagram, the target properties are represented as individual points if given as discrete values, or as a region if given as intervals. The structure and identity of candidate components is then identified by combining or ''mixing'' molecular fragments until the resulting properties match the targets.

An MINLP model for the simultaneous integration of energy, mass and properties in water networks

“…Indexes i process stream j process sink k stage in the superstructure p property p a second property to be treated r fresh source Sets NCOLD set for cold process streams NFRESH set for fresh sources NHOT set for hot process streams NPROP set for properties NSINK set for process sinks NSOURCE set for process sources upper limit for temperature difference T min minimum temperature approach (p) min minimum property operator for property p (p) max maximum property operator for property p Positive variables f i,w segregated flowrate for process stream to the waste f i,j segregated flowrate for process stream to heat transfer f i,j,0 segregated flowrate for process stream directed to process sink f i,j,p segregated flowrate for process stream to the property treatment f i,j,p,p segregated flowrate for process stream to second property interceptor F r total flowrate for fresh source f r,j segregated flowrate for fresh source to the sinks F w total flowrate for waste q i,j,i ,j ,k heat transferred between process streams in stage k T temperature T k i,j,k temperature for border k TAC total annual cost w waste stream (p) property operator for property p Binary variable y i,j,i ,j ,k binary variable for existence of heat exchangers well as for applications for dealing with reverse problem forumulations (Eljack et al, 2005) and the simultaneous consideration of process and product design Eljack et al, 2007;Kazantzi et al, 2007). After the development of pinch concepts that gave rise to the mass, energy and property integration tasks, the use of mathematical programming techniques that took advantage of more powerful computing resources and deeper theory on the subject was reported.…”

Optimization‐based framework for computer‐aided molecular design

“…The descriptor set used for the problem is chosen to be the same one used in Ref. 30, that is, ACH 3 ; > CH 2 ; ½ ACH 2 OA; ACH 2 N <; CH 3 N <; CH 3 C @O ð Þ <; ACOOH.…”

“…Simultaneous process and product design were used in Ref. 30 to formulate the solvent design problem by identifying suitable property targets. These targets are based on process requirements of zero sulfur content, limited molar volume, and low-vapor pressure.…”

An algebraic approach for simultaneous solution of process and molecular design problems

“…Processes and molecules can be represented by their properties through the Property Integration framework (Shelley and El-Halwagi, 2000;Eden et al, 2003a;Eljack et al, 2007). The key point lies in targeting the optimal property ranges of the desired molecules for a given process performance.…”

“…Employing systematic algebraic techniques to design molecules based on GCM decreases the permutations of groups that need to be checked if they have a valid molecule hidden in them. Algorithms to identify the molecules that meet the process targets have been developed by many research groups, including Marcoulaki and Kokossis (1998), Harper et al (1999), Harper and Gani (2000), Eljack et al (2007) and Chemmangattuvalappil et al (2009). In this contribution, the focus is to introduce methods that improve the efficiency of solving the molecular design problem as part of the simultaneous solution of process and product design problems.…”