A Multiphysics modelling approach of stripping Ethanol from Ethanol-Water mixture using hot microbubbles

Abstract

Ethanol has always been an integral part of our daily life. We often use ethanol knowingly or unknowingly in many formats. Industrialists use ethanol as a primary or secondary solvent in the synthesis of organic materials, as a cleaning/ sanitising solvent which can sanitise the area where it is applied onto. As a fuel, ethanol can be used as an additive to standard gasoline to make the fuel cleaner and greener. A greener commute/ travel is currently possible dominantly with the usage of electric vehicles (EVs). However, the EV infrastructure is in the primitive stages where the growth is not that exceptional as it expected but there is a steady growth. To catch up with the conventional fuels, it would take a considerable amount of time. In order to cut down the carbon footprint in the present, the addition of green additives in the fuels are the suggested actions. With countries like India initiating the action to bring down the gasoline consumption by increasing the ethanol content to a 20% by 2030, there is a good market for additives like ethanol and butanol which can be produced using a green way. There is also a concern with backwards compatibility of the EV with fuel which is not compatible. To make majority of the vehicles cleaner and greener bio-based additives are the go-to. The necessity of biofuels due to the reasons above has increased in the recent years which led to an increase in the production and the costs associated with the production. To cut down the costs associated with the production; process intensification techniques are utilised to reduce the time to process the raw materials to products. Intensification techniques like reactive distillation, pervaporation had been the norm to perform two-unit operations in the same machinery. In the recent years with the introduction of microbubbles, the addition of hot microbubbles has solved the long unsolved Mpemba effect along with the ability to perform multiple unit operations altogether. This project aspires to develop a Multiphysics model where the modelled system initially represents a single air microbubble in a reservoir of a binary mixture of ethanol and water in a 2-D axisymmetric domain and perform a parametric sweep on the bubble to incorporate hotter bubbles and observe its behaviour. The model is scaled up to a two-bubble system to find the optimum separation of bubbles where interaction is nil and the heat distribution I even across the system. A 3-D geometry is generated with the simulation from the 2-bubble system using the optimal distance where bubbles are generated using COMSOL’s application builder to build the ideal microbubble system and simulate the same