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NETmix is a novel static mixing technology consisting on a network of unit cells, comprising chambers interconnected by channels. To assess the heat transfer capacity of NETmix, the NUB model was implemented to perform hydrodynamics and heat transfer simulations. Due to the periodic nature of the NETmix structure, two central chambers and six half‐chambers were found to be sufficient to be representative of the whole network. The Nusselt numbers were determined based on the CFD simulations, and when compared with theoretical results for laminar flow between parallel plates, 3–5 times higher Nusselt number values were obtained with NETmix. This observed heat transfer rate enhancement, makes it suitable for fast reactions where heat transfer is crucial. Finally, results obtained from this study show that NETmix presents a heat transfer capacity one order of magnitude greater than microreactors, and 2–5 orders of magnitude greater than the most commonly used devices in industry. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2496–2508, 2017

Gas hydrates have been potentially recognized for developing new technologies for CO2 capture and storage; however, the respective industrialization faces difficulties. Hydrate's crystallization is highly exothermic, 1.3 kJ tonne−1 of captured CO2, and it only occurs in a narrow window of temperatures, typically 1–5 °C. Previous works have systematically reported low space–time yields (STY) due to low specific heat and mass transfer rates of the technologies tested. Herein, NetMIX, a novel mixing technology, is used for the continuous production of CO2 hydrates. NetMIX is a structured mixer consisting of a network of unit cells comprising mixing chambers interconnected by channels. The device used here has specific heat transfer rates ranging from 107 to 108 W m − 3  °C − 1 . The setup proves to be capable of producing hydrates at a STY of 200 tonne h − 1 normalm − 3 , two orders of magnitude larger than other technologies, resulting in a slurry with more than 20 wt% of CO2 inside the hydrates lattice. The solid is characterized, and a cubic structure I (sI) hydrate structure is detected, with no ice traces. Moreover, results indicate that the process is stable, and no plugging occurs, crucial for industrialization.

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