Evaluation of a novel gas-liquid contactor/reactor system for natural gas applications

In this study, a novel system for contacting gases and liquids, which may be suitable for many applications involving gas-liquid contact or gas-liquid reactions, has been developed and characterized. The system consists of a vertical vessel with gas and liquid ports and inert particles. The gas is injected through a single orifice at the bottom of the vessel and leaves at the top, while the liquid feed is introduced at the top, and the effluent leaves at the bottom of the vessel through a vertical tube inserted from the top all the way to the bottom. The system involves the use of inert particles that create circular motion within the vessel, enhancing mixing and providing high gas–liquid interfacial area for effective mass transfer. The contactor system was evaluated for the capture of CO₂through reactions with ammonium hydroxide and saline wastewater, namely desalination reject brine. The effect of inert particles surface area on both CO₂capture and ions removal was evaluated. The liquid residence time distribution (RTD) was also evaluated for experiments with and without the mixing particles, using sodium hydroxide as a tracer. In addition, the system dynamic behavior was assessed through step changes in the gas flow rate, liquid flow rate and temperature. The reactor system showed high reaction efficiency, excellent mixing and very stable steady state.