Abstract: The present disclosure relates to a system including a main exterior body. The main exterior body includes (i) a return section at a bottom of the main exterior body, (ii) a gas disengagement section at a top of the main exterior body, (iii) a riser section positioned between the return section and the gas disengagement section, and (iv) a downcomer section positioned between the gas disengagement section and the return section. The system also includes one or more first spargers each having a first end and a second end opposite the first end. Each of the one or more first spargers are positioned such that the first end is outside of the main exterior body and the second end is positioned in a lower portion of the riser section of the main exterior body. The one or more first spargers are configured to supply compressed gas to the riser section of the main exterior body. The system also includes one or more second spargers each having a first end and a second end opposite the first end.