Oxygen Transfer by Air Injection in Horizontal Pipe Flow

AbstractDissolved oxygen (DO) concentration is an important water quality parameter. This paper studies the increase of DO concentration in water by air injection into a horizontal pipe flow. A 3D computational fluid dynamics model was employed to compute the water and bubble mixture flow with a DO transport model. Experiments were also conducted to validate the mathematical model. A relative saturation coefficient relationship was developed with air bubble volume fraction and travel time. An oxygen absorption efficiency is defined, and its relationship with the inlet DO concentration, air bubble volume fraction, and travel time was discussed.