Using Aspen Plus and Pro/ii to simulate the propane deasphalting process

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I have been self-studying the Aspen Plus software recently, focusing mainly on the propane deasphalting process. By applying the little knowledge I have of Pro/II along with our company’s propane deasphalting unit, I’m able to handle process modeling without any problems; however, I’m facing difficulties in entering the component data. I’m starting this thread to discuss this issue with everyone. The propylene dehydration process mainly consists of two parts: solvent extraction and solvent recovery. According to existing literature, solvent extraction can be simulated using Aspen extractor modules or distillation columns in PROII, while solvent recovery can be simply simulated using flash modules; the challenging part of the simulation is solvent extraction. The raw material for solvent extraction is mainly vacuum residue, and accurately defining the composition of this residue represents the biggest obstacle in the simulation process. The method for defining petroleum components mainly involves converting complex petroleum components into virtual components based on data such as the distillation curve of the feed and its density. Virtual components lack the corresponding functional groups to generate binary interaction parameters, nor can they establish activity coefficients between solvents and petroleum components. The liquid-liquid extraction process for propylene oxide is based on the different solubilities between the solvent and alkanes, and the binary interaction coefficient is a necessary condition for calculating the two-phase equilibrium. To address this issue, the thermodynamic equation (Chueh and Prausnitz 1967) is applied to estimate the binary interaction coefficient; this is achieved by modifying the parameters of the PRO/II thermodynamic equation, as shown in Attachment 1: Process simulation of solvent deasphalting plants with PRO/II based on thermodynamic equilibrium data. Another approach is to use the Kuop definition for the feed components. See Attachment 2: Two different approaches for RDC modeling when simulating a solvent deasphalting plant. Based on the differences in KUOP values, petroleum components are divided into three virtual components: paraffinic, naphthenic, and aromatic. Through a series of calculations, tables detailing the properties of these virtual components are obtained, which are then entered into the simulation software to define the components. The literature also mentions an AI*-based method for defining components, which will not be discussed for now. There are also many domestic studies that use this method to simulate the propylene dehydrogenation unit; see Attachments 3 and 4. After reviewing these papers, I tried to conduct simulations using Aspen with the KUOP method. The problems encountered include: how to divide narrow fractions into components based on distillation data of the actual boiling point? How to input the data from the table below into Aspen (ProII)? I am ignorant and lacking in knowledge; I hope the expert can offer some guidance!