In the reactor, bubbles are suppressed by pressurizing the liquid flowing through it.

A pressure-swing technique has been developed for controlling the generation and flow of gas in an anaerobic biological reactor and associated equipment in a system that processes wastewater. The purpose and effect of the technique is to prevent the formation of gas bubbles in the reactor; if allowed to coalesce in the reactor, gas bubbles could impede the flow of the liquid stream, rendering the treatment system less effective. The technique was conceived for application to a wastewater treatment system that would operate in microgravity, but could also be applied to bioreactor systems (e.g., fermentation systems) that operate in Earth-normal gravity.