We have just finished another successful process design project. A client needed to adapt an existing reactor to manufacture a formol-melamine resin. The heating-cooling system had to be verified for the new process conditions, and a new condensing system that should operate at full-reflux during the methylolation phase, and as an organic-aqueous phase separator during the eterification phase (a polycondensation equilibrium reaction that forms water as a by-product, which must be removed from the system in order to favor the production of the desired polymer).
A simulation model was built around the main chemical reactions and their respective thermodynamic and kinetic parameters – determined from lab and pilot plant data available within the company. The reactor and its peripherals construction features, alongside with convenient vapor-liquid and liquid-liquid equilibria methods (the latter required to predict the organic and aqueous phases in the reflux system), heat transfer and differential mass and energy balance equations, completed the model.
A simulation tool specialized in batch reactors was required to speed up the model setup, the solution of the highly nonlinear set of algebraic-differential equations and subsequent simulations performed to investigate the best equipment configuration and operational conditions. After some market research Fives-ProSim BatchReator was selected for such tool: with a rich databank of chemical compounds, thermodynamic methods, powerful solvers and a very friendly interface with a not very steep learning curve (competent instructors and support team helped a lot with that).
Batch process design is always challenging due to its transient characteristic. Through the years we have seen a lot of guesswork and proprietary rules-of-thumb in this area, resulting in oversized equipment, undersized utility systems and sometimes very dangerous operating conditions, the result of a complete lack of knowledge of how the variables of interest behave over time.
Competitive markets such as specialty chemicals, resins for paints, energetic materials and others that make their products batchwise have no more room for amateurism. We are here to help.