Effect of Binary Interaction Parameters (BIP) on simulation of distillation column Naitik Choksi Dept. of Chemical Engineering Nirma University Ahmedabad, India naitikchoksi@yahoo.co.in Tushar Perkar Dept. of Chemical Engineering Nirma University Ahmedabad, India tusharperkar97@gmail.com Dr. Milind Joshipura Dept. of Chemical Engineering Nirma University Ahmedabad, India milind.joshipura@nirmauni.ac.in Abstract— In the present paper, Aspen HYSYS is used as a simulator to showcase the effect of Binary Interaction Parameters (BIP’s) on the results of Shortcut Distillation simulations. Out of the 46 binary systems considered, 40 of them did not have inbuilt BIP’s in Aspen HYSYS. We simulated 23 systems using the Wilson fluid package and 17 systems using NRTL. The boiling point differences between the two components in the systems ranged from 2.4 to 84.9⁰C. The maximum Global %AAD obtained for Wilson was 19.2%, while the maximum Global %AAD obtained for NRTL was 3.3%. The NRTL model gave smaller deviations than Wilson, and therefore is considered as more stable. These results will surely help to improve the simulations of Shortcut Distillation with proper use of BIP’s and further help to decrease the errors in design of distillation columns. Keywords—Aspen HYSYS, Shortcut Distillation, Binary Interaction Parameters, NRTL, Wilson. I. INTRODUCTION Process Simulation covers the entire life cycle of the process, from R&D to conceptual design to plant operations. It is a very important part of process design as it allows engineers to model a process virtually without having to invest manpower, money or time to physically test their design in the real environment. Steady state simulations are performed during the design phase to understand how the design can be modified to get the most optimum results, both from engineering and business point of view. Dynamic simulations allow the engineer to virtually run the designed process under different conditions to ensure that the process remains stable and safe under extreme or abnormal conditions. Therefore, simulation helps to eliminate the cost and time required for physical testing of the design, to optimise the design from engineering and business point of view and to test the safety of the process. A. Simulation of distillation column: Distillation is the separation of key components of a stream on the basis of the difference in their relative volatilities, or boiling points. It is the most widely used unit operation to achieve separation with maximum purity possible. Due to its prevalent usage in any chemical industry, it has become necessary to simulate the distillation operation first and then design and fabricate it. The simulation of distillation provides an insight into the operating costs and capital costs that would be involved, by furnishing the data of number of stages of the column, the reboiler and condenser duties, the reflux ratio required for the required purity. B. Impact of thermodynamic models In today's generation chemical engineers often find themselves to be dependent on powerful process simulation software, programs for projects in their occupation or any form of research. It is likely to be seen that due to the lack of experience in operation of process simulators, they end up making a poor choice in selecting a physical property package or not specifying the binary interacting parameters for a system of components. Legitimate choice of proper binary interaction parameters and thermodynamic models amid process simulation is essential as a beginning stage for precise process re- enactment. A completely optimized process in terms of operating parameters, equipment selection, unit operations etc. is completely worthless if simulation relies on inappropriate thermodynamic models. It is observed that an inaccurate choice of thermodynamic models has a strong impact on the field of designing. For example, the design margins that we obtain through simulations may be greater than what is needed and this effect significantly magnifies the cost of the project, induces poor design choices, and ultimately results in reduced production capacity. Thermodynamic model at the same time also affects the rating and sizing of the process equipment hence the efficiency and accuracy of unit operations and processes. According to our literature survey, we found that research has been done on the impact of selection of thermodynamic packages on the results of simulation [1], but very less research has been done on the impact of binary interaction parameters on the results of distillation simulation, due to which we performed a study on the impact of binary interaction parameters on the results of ShortCut Distillation (SCD) using Aspen HYSYS. II. DATABASE AND METHODOLOGY: VLE Data along with binary interaction parameters (BIP’s) for 46 binary systems were collected. All these systems were checked in Aspen HYSYS’s component library for availability of inbuilt BIP’s. Systems were then bifurcated on the basis of presence of BIP’s in HYSYS. Systems without BIP’s were used for simulation, while those systems which had inbuilt BIP’s were eliminated. Total 40 cases were simulated using Wilson and NRTL, as